Information on EC 1.2.4.4 - 3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring)

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The expected taxonomic range for this enzyme is: Eukaryota, Bacteria, Archaea

EC NUMBER
COMMENTARY
1.2.4.4
-
RECOMMENDED NAME
GeneOntology No.
3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring)
REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
3-methyl-2-oxobutanoate + [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] lipoyllysine = [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(2-methylpropanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
-
-
-
-
3-methyl-2-oxobutanoate + [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] lipoyllysine = [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(2-methylpropanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
the multienzyme complex catalyzes a thiamine diphosphate- and Mg2+-dependent oxidative decarboxylation of branched-chain keto acids with the formation of branched-chain acyl-CoA and reduction of NAD+ to NADH: R1R2CHCOCOOH + NAD+ + CoASH = R1R2CHCO-S-CoA + NADH + CO2, component E1 (EC 1.2.4.4, branched-chain keto acid dehydrogenase), component E2 (no EC number, branched-chain acyltransferase), component E3 (EC 1.8.1.4, dihydrolipoamide dehydrogenase), partial reactions catalyzed by the multienzyme complex: 1. R1R2CHCOCOOH + E1-(thiamine diphosphate) = E1-(thiamine diphosphate)-COHCHR1R2 + CO2, 2. E1-(thiamine diphosphate)-COHCHR1R2 + lipoyl-E2 = R1R2CHCO-SCoA + dihydrolipoyl-E2, 4. dihydrolipoyl-E2 + NAD+ = lipoyl-E2 + NADH, the multienzyme complex also contains small amounts of a specific kinase and a specific phosphatase which modulate the activity of E1 by phosphorylation and dephosphorylation
-
3-methyl-2-oxobutanoate + [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] lipoyllysine = [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(2-methylpropanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
residues His146beta' and His291alpha of E1b component are essential for catalysis
-
3-methyl-2-oxobutanoate + [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] lipoyllysine = [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(2-methylpropanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
substrate recognition and reaction mechanism
-
3-methyl-2-oxobutanoate + [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] lipoyllysine = [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(2-methylpropanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
substrate recognition and reaction mechanism, involving residues Gly131beta-Gln131beta, Phe66alpha, Tyr86beta, Tyr95alpha, Met128alpha, His131alpha of component E1
-
REACTION TYPE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
oxidation
-
-
-
-
oxidative decarboxylation
-
-
-
-
oxidative decarboxylation
-
-
redox reaction
-
-
-
-
reduction
-
-
-
-
PATHWAY
KEGG Link
MetaCyc Link
(S)-3-methyl-2-oxopentanoate dehydrogenase (acylating)
-
2-oxoisovalerate decarboxylation to isobutanoyl-CoA
-
4-methyl-2-oxopentanoate dehydrogenase (acylating)
-
Biosynthesis of secondary metabolites
-
Metabolic pathways
-
Valine, leucine and isoleucine degradation
-
SYSTEMATIC NAME
IUBMB Comments
3-methyl-2-oxobutanoate:[dihydrolipoyllysine-residue (2-methylpropanoyl)transferase]-lipoyllysine 2-oxidoreductase (decarboxylating, acceptor-2-methylpropanoylating)
Contains thiamine diphosphate. It acts not only on 3-methyl-2-oxobutanaoate, but also on 4-methyl-2-oxopentanoate and (S)-3-methyl-2-oxopentanoate, so that it acts on the 2-oxo acids that derive from the action of transaminases on valine, leucine and isoleucine. It is a component of the multienzyme 3-methyl-2-oxobutanoate dehydrogenase complex in which multiple copies of it are bound to a core of molecules of EC 2.3.1.168, dihydrolipoyllysine-residue (2-methylpropanoyl)transferase, which also binds multiple copies of EC 1.8.1.4, dihydrolipoyl dehydrogenase. It does not act on free lipoamide or lipoyllysine, but only on the lipoyllysine residue in EC 2.3.1.168.
SYNONYMS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
(R)-2-hydroxyisocaproate dehydrogenase
Clostridium difficile
Q5U922
-
2-oxoisocaproate dehydrogenase
-
-
-
-
2-oxoisovalerate dehydrogenase (lipoate)
-
-
-
-
alpha-keto-beta-methylvalerate dehydrogenase
-
-
-
-
alpha-ketoacid dehydrogenase
-
i.e. E1b enzyme complex component
alpha-ketoisocaproate dehydrogenase
-
-
-
-
alpha-ketoisocaproic dehydrogenase
-
-
-
-
alpha-ketoisocaproic-alpha-keto-beta-methylvaleric dehydrogenase
-
-
-
-
alpha-ketoisovalerate dehydrogenase
-
-
-
-
alpha-oxoisocaproate dehydrogenase
-
-
-
-
BCDH
-
-
-
-
BCKADC
-
-
-
-
BCKDC
-
-
BCKDH
-
-
-
-
BCKDH
-
-
BCKDH E1-alpha
-
-
-
-
BCKDH E1-beta
-
-
-
-
BCKDHB
-
-
BCOAD
-
-
-
-
branched chain alpha-ketoacid dehydrogenase complex
-
-
branched chain alpha-ketoacid dehydrogenase complex
-
-
branched chain alpha-ketoacid dehydrogenase complex
-
components E2 and E1
branched chain keto acid dehydrogenase
-
-
-
-
branched-chain (-2-oxoacid BCD) dehydrogenase
-
-
-
-
branched-chain 2-keto acid dehydrogenase
-
-
-
-
branched-chain 2-oxo acid dehydrogenase
-
-
-
-
branched-chain alpha-keto acid decarboxylase/dehydrogenase
-
-
branched-chain alpha-keto acid dehydrogenase
-
-
-
-
branched-chain alpha-keto acid dehydrogenase
-
-
branched-chain alpha-keto acid dehydrogenase
-
-
branched-chain alpha-keto acid dehydrogenase
-
-
branched-chain alpha-keto acid dehydrogenase complex
-
-
branched-chain alpha-keto acid dehydrogenase complex
-
-
branched-chain alpha-keto acid dehydrogenase complex
-
-
branched-chain alpha-keto acid dehydrogenase complex
-
-
branched-chain alpha-keto acid dehydrogenase complex
-
-
branched-chain alpha-keto acid dehydrogenase E1beta subunit
-
-
branched-chain alpha-ketoacid dehydrogenase complex
-
-
branched-chain alpha-ketoacid dehydrogenase complex
-
-
branched-chain alpha-ketoacid dehydrogenase enzyme complex
-
-
branched-chain alpha-ketoacid dehydrogenase multienzyme complex
-
-
branched-chain alpha-oxo acid dehydrogenase
-
-
-
-
branched-chain keto acid dehydrogenase
-
-
-
-
branched-chain keto acid dehydrogenase
-
contains three components: E1 (alpha2/beta2, dehydrogenase-decarboxylase), E2 (transacylase), and E3 (lipoamide dehydrogenase)
branched-chain keto acid dehydrogenase complex
-
-
branched-chain ketoacid dehydrogenase
-
-
-
-
dehydrogenase, 2-oxoisocaproate
-
-
-
-
dehydrogenase, 2-oxoisovalerate (lipoate)
-
-
-
-
dehydrogenase, branched chain alpha-keto acid
-
-
-
-
dihydrolipoyl acyl-transferase
-
part of the branched-chain 2-oxoacid dehydrogenase complex (E2)
dihydrolipoyl acyl-transferase
-
E2 component of the branched-chain 2-oxoacid dehydrogenase complex
dihydrolipoyl transacylase
-
i.e. E2b enzyme complex component
dihydrolipoyl transacylase
Q8QHL7
-
dihydrolipoyl transacylase
-
E2
E1b component
-
-
E1b component of the 2-oxo acid dehydrogenase complex
-
-
EC 1.2.4.3
-
-
formerly
-
additional information
-
; scaffold of the human branched-chain alpha-ketoacid dehydrogenase complex, contains the lipoyl-bearing domain (hbLBD), the subunit-binding domain (hbSBD) and the inner core domain that are linked to carry out E2 functions in substrate channeling and recognition
additional information
-
E1b and E2b are components of the branched-chain alpha-ketoacid dehydrogenase multienzyme complex BCKD
additional information
-
E1b and E2b are components of the branched-chain alpha-ketoacid dehydrogenase multienzyme complex BCKDC
additional information
-
lipoic acid bearing domain hbLBD is a domain of the E2 component of the branched chain alpha-ketoacid dehydrogenase complex BCKD
CAS REGISTRY NUMBER
COMMENTARY
9031-05-4
-
9082-72-8
-
ORGANISM
COMMENTARY
LITERATURE
SEQUENCE CODE
SEQUENCE DB
SOURCE
Clostridium difficile
DSM 1296T
SwissProt
Manually annotated by BRENDA team
strain DSM 3757
-
-
Manually annotated by BRENDA team
the lipoic acid-bearing domain is part of the E2 transacylase subunit of the branched-chain alpha-keto acid dehydrogenase complex
-
-
Manually annotated by BRENDA team
E2 component; rainbow trout, the enzyme is the E2 dihydrolipoyl transacylase subunit of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
SwissProt
Manually annotated by BRENDA team
; female Wistar rats
-
-
Manually annotated by BRENDA team
E2 component; E1 alpha-keto acid decarboxylase and E2 dihydrolipoyl transacylase are subunits of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
SwissProt
Manually annotated by BRENDA team
strain HB8
-
-
Manually annotated by BRENDA team
GENERAL INFORMATION
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
malfunction
-
maple syrup urine disease is an autosomal recessive metabolic disorder resulting from a deficiency in the branched-chain alpha-keto acid dehydrogenase complex
malfunction
-
maple syrup urine disease is an inborn error of metabolism of the branched chain alpha-ketoacid dehydrogenase complex
malfunction
-
maple syrup urine disease results from genetic enzyme defects, which lead to accumulation of toxic levels of branched chain amino acids and branched-chain alpha-keto acids that result in brain swelling
SUBSTRATE
PRODUCT                      
REACTION DIAGRAM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
2-oxo-4-methylthiobutanoate + NAD+ + CoA
3-methylthiopropionyl-CoA + NADH + CO2
show the reaction diagram
-
-
-
-
?
2-oxo-4-methylthiobutanoate + NAD+ + CoA
3-methylthiopropionyl-CoA + NADH + CO2
show the reaction diagram
-
-
-
-
?
2-oxo-4-methylthiobutanoate + NAD+ + CoA
3-methylthiopropionyl-CoA + NADH + CO2
show the reaction diagram
-
38% of the activity with 3-methyl-2-oxobutanoate
-
-
?
2-oxo-beta-methylvalerate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
Q8QHL7
overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxo-beta-methylvalerate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
Q99PU6
overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxo-butyrate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
Q8QHL7
overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxo-butyrate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
Q99PU6
overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxo-gamma-methylthiobutyrate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
Q8QHL7
low activity, overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxo-gamma-methylthiobutyrate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
Q99PU6
low activity, overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxo-glutarate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
Q8QHL7
low activity, overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxo-glutarate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
Q99PU6
low activity, overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxo-isocaproate + NAD+ + CoA
3-methylbutanoyl-CoA + CO2 + NADH + H+
show the reaction diagram
-
-
-
-
?
2-oxo-isocaproate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
Q8QHL7
overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxo-isocaproate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
Q99PU6
overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxo-isocaproate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
-
overall reaction of the recombinant branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxobutanoate + NAD+ + CoA
propionyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
2-oxobutanoate + NAD+ + CoA
propionyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
2-oxobutanoate + NAD+ + CoA
propionyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
2-oxobutanoate + NAD+ + CoA
propionyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
2-oxobutanoate + NAD+ + CoA
propionyl-CoA + CO2 + NADH
show the reaction diagram
-
20% of the activity with 3-methyl-2-oxobutanoate
-
-
-
2-oxobutanoate + NAD+ + CoA
propionyl-CoA + CO2 + NADH
show the reaction diagram
-
50% of the activity with 3-methyl-2-oxobutanoate
-
-
?
2-oxobutanoate + NAD+ + CoA
propionyl-CoA + CO2 + NADH
show the reaction diagram
-
2-oxobutanoate
-
-
-
2-oxobutanoate + NAD+ + CoA
propionyl-CoA + CO2 + NADH
show the reaction diagram
-
2-oxobutanoate
-
-
?
2-oxoglutarate + NAD+ + CoA
3-carboxypropionyl-CoA + NADH + CO2
show the reaction diagram
-
-
-
-
?
2-oxoglutarate + NAD+ + CoA
3-carboxypropionyl-CoA + NADH + CO2
show the reaction diagram
-
no activity
-
-
-
2-oxoglutarate + NAD+ + CoA
3-carboxypropionyl-CoA + NADH + CO2
show the reaction diagram
-
poor substrate
-
-
?
2-oxohexanoate + NADH
(R)-2-hydroxyhexanoate + NAD+
show the reaction diagram
Clostridium difficile
-, Q5U922
-
-
-
?
2-oxoisocaproate + NADH
(R)-2-hydroxyisocaproate + NAD+
show the reaction diagram
Clostridium difficile
-, Q5U922
-
-
-
ir
2-oxoisovalerate + 2,6-dichlorophenol indophenol
? + CO2
show the reaction diagram
-
-
-
-
?
2-oxoisovalerate + 2,6-dichlorophenolindophenol + CoA
? + CO2 + reduced 2,6-dichlorophenolindophenol
show the reaction diagram
-
-
-
-
?
2-oxoisovalerate + NAD+
? + NADH
show the reaction diagram
-
-
-
-
?
2-oxoisovalerate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase] lipoyllysine
?
show the reaction diagram
-
-
-
-
?
2-oxoisovalerate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
Q8QHL7
overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxoisovalerate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
Q99PU6
overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxoisovalerate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
?
show the reaction diagram
-
overall reaction of the recombinant branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxoisovalerate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
? + CO2
show the reaction diagram
-
-
-
-
?
2-oxoisovalerate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
[dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-butanoyl-dihydrolipoyllysine + CO2
show the reaction diagram
-
overall reaction of the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH
-
-
?
2-oxopentanoate + NAD+ + CoA
butanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
2-oxopentanoate + NADH
(R)-2-hydroxypentanoate + NAD+
show the reaction diagram
Clostridium difficile
-, Q5U922
-
-
-
?
3-methyl-2-oxobutanoate + NAD+ + CoA
2-methylpropanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxobutanoate + NAD+ + CoA
2-methylpropanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxobutanoate + NAD+ + CoA
2-methylpropanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxobutanoate + NAD+ + CoA
2-methylpropanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxobutanoate + NAD+ + CoA
2-methylpropanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxobutanoate + NAD+ + CoA
2-methylpropanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxobutanoate + NAD+ + CoA
2-methylpropanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxobutanoate + NAD+ + CoA
2-methylpropanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxobutanoate + NAD+ + CoA
2-methylpropanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
?
3-methyl-2-oxobutanoate + NAD+ + CoA
2-methylpropanoyl-CoA + CO2 + NADH
show the reaction diagram
Pseudomonas putida PpG2
-
-
-
-
?
3-methyl-2-oxobutanoate + NAD+ + CoA
2-methylpropanoyl-CoA + CO2 + NADH + H+
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxobutanoate + [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] lipoyllysine
[dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(2-methylpropanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxobutanoate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
[dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(2-methylpropanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
-
-
-
-
r
3-methyl-2-oxobutanoate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
[dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(2-methylpropanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxopentanoate + NAD+ + CoA
2-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxopentanoate + NAD+ + CoA
2-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxopentanoate + NAD+ + CoA
2-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxopentanoate + NAD+ + CoA
2-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxopentanoate + NAD+ + CoA
2-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxopentanoate + NAD+ + CoA
2-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxopentanoate + NAD+ + CoA
2-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxopentanoate + NAD+ + CoA
2-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
38% of the activity with 3-methyl-2-oxobutanoate
-
-
?
3-methyl-2-oxopentanoate + NAD+ + CoA
2-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
D-3-methyl-2-oxopentanoate and L-3-methyl-2-oxopentanoate
-
-
?
3-methyl-2-oxopentanoate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
[dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(2-methylbutanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
-
-
-
-
r
4-methyl-2-oxopentanoate + NAD+ + CoA
3-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
4-methyl-2-oxopentanoate + NAD+ + CoA
3-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
4-methyl-2-oxopentanoate + NAD+ + CoA
3-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
4-methyl-2-oxopentanoate + NAD+ + CoA
3-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
4-methyl-2-oxopentanoate + NAD+ + CoA
3-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
4-methyl-2-oxopentanoate + NAD+ + CoA
3-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
4-methyl-2-oxopentanoate + NAD+ + CoA
3-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
?
4-methyl-2-oxopentanoate + NAD+ + CoA
3-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
?
4-methyl-2-oxopentanoate + NAD+ + CoA
3-methylbutanoyl-CoA + CO2 + NADH
show the reaction diagram
-
38% of the activity with 3-methyl-2-oxobutanoate
-
-
?
4-methyl-2-oxopentanoate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
[dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(3-methylbutanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
-
-
-
-
r
acyl-E1b-thiamine diphosphate + lipoyl-[lipoic acid-bearing domain]
2-oxo-acyl-S-lipoyl-[lipoic acid-bearing domain] + E1b-thiamine diphosphate
show the reaction diagram
-
reductive acylation of lipoyl-LBD
-
-
?
alpha-keto-beta-methylvaleric acid + NADH
?
show the reaction diagram
-
-
-
-
?
alpha-ketoisocaproic acid + NADH
?
show the reaction diagram
-
-
-
-
?
alpha-ketoisovaleric acid + NADH
?
show the reaction diagram
-
-
-
-
?
phenylpyruvate + NADH
NAD+ + phenylalanine
show the reaction diagram
Clostridium difficile
-, Q5U922
-
-
-
?
pyruvate + NAD+ + CoA
acetyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
pyruvate + NAD+ + CoA
acetyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
pyruvate + NAD+ + CoA
acetyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
-
pyruvate + NAD+ + CoA
acetyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
pyruvate + NAD+ + CoA
acetyl-CoA + CO2 + NADH
show the reaction diagram
-
-
-
-
?
pyruvate + NAD+ + CoA
acetyl-CoA + CO2 + NADH
show the reaction diagram
-
no activity
-
-
-
pyruvate + NAD+ + CoA
acetyl-CoA + CO2 + NADH
show the reaction diagram
-
poor substrate
-
-
?
pyruvate + NAD+ + CoA
acetyl-CoA + CO2 + NADH
show the reaction diagram
-
20% of the activity with 3-methyl-2-oxobutanoate
-
-
?
E1b-thiamine diphosphate + 2-oxo-acid
E1b-thiamine diphosphate-acyl + CO2
show the reaction diagram
-
decarboxylation, His146beta' and His291alpha are involved
-
-
?
additional information
?
-
-
-
-
-
-
additional information
?
-
-
enzyme probably is identical with EC 1.2.1.25
-
-
-
additional information
?
-
-
the multienzyme complex catalyzes a thiamine diphosphate- and Mg2+-dependent oxidative decarboxylation of branched-chain keto acids with the formation of branched-chain acyl-CoA and reduction of NAD+ to NADH: R1R2CHCOCOOH + NAD+ + CoASH = R1R2CHCO-S-CoA + NADH + CO2, component E1 (EC 1.2.4.4, branched-chain keto acid dehydrogenase), component E2 (no EC number, branched-chain acyltransferase), component E3 (EC 1.8.1.4, dihydrolipoamide dehydrogenase), partial reactions catalyzed by the multienzyme complex: 1. R1R2CHCOCOOH + E1-(thiamine diphosphate) = E1-(thiamine diphosphate)-COHCHR1R2 + CO2, 2. E1(thiamine diphosphate)-C(OH)CHR1R2 + lipoyl-E2 = R1R2CHCO-SCoA + dihydrolipoyl-E2, 4. dihydrolipoyl-E2 + NAD+ = lipoyl-E2 + NADH
-
-
-
additional information
?
-
Q99PU6
pyruvate is a poor substrate
-
-
-
additional information
?
-
-
the enzyme complex is regulated by reversible phosphorylation, complex is inactive in the phosphorylated form and active in the dephosphorylated form
-
-
-
additional information
?
-
-
starvation causes a significant decrease in activity in maternal tissues
-
-
-
additional information
?
-
-
patients with type IA maple syrup urine disease show missense mutations in the E1 alpha-subunit resulting in the loss of E1 and branched-chain ketoacid dehydrogenase activity
-
-
-
additional information
?
-
-
the enzyme catalyzes a reaction of branched-chain amino acid catabolism which constitutes a crucial step to provide fatty acid precursors for antibiotic biosynthesis
-
-
-
additional information
?
-
-
the intramitochondrial pyruvate dehydrogenase complex and the branched-chain 2-oxo acid dehydrogenase complex are responsible for the oxidative decarboxylation of 2-oxobutanoate, the branched-chain 2-oxo acid dehydrogenase complex is probably the more important complex
-
-
-
additional information
?
-
-
thiamine increases the specific activity of the human liver enzyme complex
-
-
-
additional information
?
-
-
enzyme complex is induced by growth on branched-chain amino acid or keto acid and repressed by growth in the presence of glucose or ammonium ion
-
-
-
additional information
?
-
-
the enzyme can be regulated by an endogenous protein kinase
-
-
-
additional information
?
-
-
the multienzyme complex is able to activate the branched fatty acids which are formed by transamination of Leu, Val, and Ile
-
-
-
additional information
?
-
-
high-protein diet increases the enzyme concentration in rat liver, protein-free diet decreases enzyme concentration in rat liver
-
-
-
additional information
?
-
-
enzyme is involved in the catabolism of branched-chain 2-oxo acids
-
-
-
additional information
?
-
-
regulation of the enzyme complex by phosphorylation and dephosphorylation
-
-
-
additional information
?
-
-
the activity of the multienzyme complex is regulated by reversible phosphorylation of the alpha-subunit of the E1 component, EC 1.2.4.4.
-
-
-
additional information
?
-
-
regulation by phosphorylation-dephosphorylation
-
-
-
additional information
?
-
-
regulation by phosphorylation-dephosphorylation
-
-
-
additional information
?
-
-
branched-chain alpha-ketoacid dehydrogenase multienzyme complex BCKDC which is regulated by phosphorylation of component E1b, residue Ser292 of the alpha-domain, in response to hormone and dietary stimuli, phosphorylation induces a conformational change of E1b phosphorylation loop which prevents binding of the E2b component, thiamine diphosphate and His291alpha are involved, overview
-
-
-
additional information
?
-
-
enzyme regulates the catabolism of branched-chain amino acids, and is regulated by phosphorylation-dephosphorylation
-
-
-
additional information
?
-
-
enzyme-deficiency leads to inherited marple syrup urine disease MSUD
-
-
-
additional information
?
-
Q99PU6
key enzyme in the branched-chain amino acids catabolism
-
-
-
additional information
?
-
-
the lipoic acid-bearing domain of enzyme complex component E2 plays a central role in substrate channeling in the mitochondrial multienzyme complex
-
-
-
additional information
?
-
-
decarboxylation and acylation reaction proceeds in 4 reaction steps in the enzyme complex, involving the cofactor thiamine diphosphate and the lipoic acid-bearing domain of component E2, E1 undergoes an open-closed conformational change upon formation of the enzyme-substrate complex, overview
-
-
-
additional information
?
-
-
E1 and E2 components of the complex act in tandem, the lipoic acid-bearing domain plays an important role in substrate channeling in oxidative decarboxylation of the branched chain alpha-ketoacids within the dehydrogenase multienzyme complex
-
-
-
additional information
?
-
-
multistep reaction of the enzyme complex, overview
-
-
-
additional information
?
-
-
overall reaction
-
-
-
additional information
?
-
Q8QHL7
pyruvate is a poor substrate, the E2 subunits' inter-domain segments affect the overall activity
-
-
-
additional information
?
-
-
the overall reaction proceeds in several steps of the components E1, E2, and E3, overview, conformation of the conserved phosphorylation loop, carrying 2 phosphorylation sites Ser292alpha andSer302alpha, is essential for recognition of lipoylated LBD to initiate E1b-catalyzed reductive acylation, E1b is regulated by reversible phosphorylation through the kinase of the multienzyme complex
-
-
-
additional information
?
-
Clostridium difficile
-, Q5U922
2-oxoisovalerate and 2-oxobutyrate are not accepted as substrates
-
-
-
additional information
?
-
-
flux-generating step for branched-chain amino acid catabolism
-
-
-
additional information
?
-
P35738
does not interact with human mitochondrial branched-chain aminotransferase isozymes
-
-
-
additional information
?
-
-
branched-chain alpha-keto acid dehydrogenase complex is essentially devoid of the constituent dihydrolipoamide dehydrogenase component (E3). The absence of E3 is associated with the low affinity of the subunit-binding domain of human BCKDC for hE3
-
-
-
NATURAL SUBSTRATES
NATURAL PRODUCTS
REACTION DIAGRAM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
2-oxo-isocaproate + NAD+ + CoA
3-methylbutanoyl-CoA + CO2 + NADH + H+
show the reaction diagram
-
-
-
-
?
2-oxoisocaproate + NADH
(R)-2-hydroxyisocaproate + NAD+
show the reaction diagram
Clostridium difficile
-, Q5U922
-
-
-
ir
3-methyl-2-oxobutanoate + NAD+ + CoA
2-methylpropanoyl-CoA + CO2 + NADH + H+
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxobutanoate + [dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] lipoyllysine
[dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(2-methylpropanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
-
-
-
-
?
3-methyl-2-oxobutanoate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
[dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(2-methylpropanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
-
-
-
-
r
3-methyl-2-oxobutanoate + [dihydrolipoyllysine-residue(2-methylpropanoyl)transferase]-lipoyllysine
[dihydrolipoyllysine-residue (2-methylpropanoyl)transferase] S-(2-methylpropanoyl)dihydrolipoyllysine + CO2
show the reaction diagram
-
-
-
-
?
alpha-keto-beta-methylvaleric acid + NADH
?
show the reaction diagram
-
-
-
-
?
alpha-ketoisocaproic acid + NADH
?
show the reaction diagram
-
-
-
-
?
alpha-ketoisovaleric acid + NADH
?
show the reaction diagram
-
-
-
-
?
additional information
?
-
-
-
-
-
-
additional information
?
-
-
the enzyme complex is regulated by reversible phosphorylation, complex is inactive in the phosphorylated form and active in the dephosphorylated form
-
-
-
additional information
?
-
-
starvation causes a significant decrease in activity in maternal tissues
-
-
-
additional information
?
-
-
patients with type IA maple syrup urine disease show missense mutations in the E1 alpha-subunit resulting in the loss of E1 and branched-chain ketoacid dehydrogenase activity
-
-
-
additional information
?
-
-
the enzyme catalyzes a reaction of branched-chain amino acid catabolism which constitutes a crucial step to provide fatty acid precursors for antibiotic biosynthesis
-
-
-
additional information
?
-
-
the intramitochondrial pyruvate dehydrogenase complex and the branched-chain 2-oxo acid dehydrogenase complex are responsible for the oxidative decarboxylation of 2-oxobutanoate, the branched-chain 2-oxo acid dehydrogenase complex is probably the more important complex
-
-
-
additional information
?
-
-
thiamine increases the specific activity of the human liver enzyme complex
-
-
-
additional information
?
-
-
enzyme complex is induced by growth on branched-chain amino acid or keto acid and repressed by growth in the presence of glucose or ammonium ion
-
-
-
additional information
?
-
-
the enzyme can be regulated by an endogenous protein kinase
-
-
-
additional information
?
-
-
the multienzyme complex is able to activate the branched fatty acids which are formed by transamination of Leu, Val, and Ile
-
-
-
additional information
?
-
-
high-protein diet increases the enzyme concentration in rat liver, protein-free diet decreases enzyme concentration in rat liver
-
-
-
additional information
?
-
-
enzyme is involved in the catabolism of branched-chain 2-oxo acids
-
-
-
additional information
?
-
-
regulation of the enzyme complex by phosphorylation and dephosphorylation
-
-
-
additional information
?
-
-
the activity of the multienzyme complex is regulated by reversible phosphorylation of the alpha-subunit of the E1 component, EC 1.2.4.4.
-
-
-
additional information
?
-
-
regulation by phosphorylation-dephosphorylation
-
-
-
additional information
?
-
-
regulation by phosphorylation-dephosphorylation
-
-
-
additional information
?
-
-
branched-chain alpha-ketoacid dehydrogenase multienzyme complex BCKDC which is regulated by phosphorylation of component E1b, residue Ser292 of the alpha-domain, in response to hormone and dietary stimuli, phosphorylation induces a conformational change of E1b phosphorylation loop which prevents binding of the E2b component, thiamine diphosphate and His291alpha are involved, overview
-
-
-
additional information
?
-
-
enzyme regulates the catabolism of branched-chain amino acids, and is regulated by phosphorylation-dephosphorylation
-
-
-
additional information
?
-
-
enzyme-deficiency leads to inherited marple syrup urine disease MSUD
-
-
-
additional information
?
-
Q99PU6
key enzyme in the branched-chain amino acids catabolism
-
-
-
additional information
?
-
-
the lipoic acid-bearing domain of enzyme complex component E2 plays a central role in substrate channeling in the mitochondrial multienzyme complex
-
-
-
COFACTOR
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
CoA
-
the multienzyme complex catalyzes a thiamine diphosphate- and Mg2+-dependent oxidative decarboxylation of branched-chain keto acids with the formation of branched-chain acyl-CoA and reduction of NAD+ to NADH: R1R2CHCOCOOH + NAD+ + CoASH = R1R2CHCO-S-CoA + NADH + CO2, component E1 (EC 1.2.4.4, branched-chain keto acid dehydrogenase), component E2 (no EC number, branched-chain acyltransferase), component E3 (EC 1.8.1.4, dihydrolipoamide dehydrogenase), partial reactions catalyzed by the multienzyme complex: 1. R1R2CHCOCOOH + E1-(thiamine diphosphate) = E1-(thiamine diphosphate)-COHCHR1R2 + CO2, 2. E1-(thiamine diphosphate)-COHCHR1R2 + lipoyl-E2 = R1R2CHCO-SCoA + dihydrolipoyl-E2, 4. dihydrolipoyl-E2 + NAD+ = lipoyl-E2 + NADH
CoA
-
Km: 0.064 mM
CoA
-
Km: 0.0071 mM in the reaction with 4-methyl-2-oxopentanoate, Km: 0.009 mM in the reaction with 3-methyl-2-oxobutanoate, Km: 0.007 in the reaction with DL-3-methyl-2-oxopentanoate
CoA
-
extraordinarily tightly bound
NAD+
-
the multienzyme complex catalyzes a thiamine diphosphate- and Mg2+-dependent oxidative decarboxylation of branched-chain keto acids with the formation of branched-chain acyl-CoA and reduction of NAD+ to NADH: R1R2CHCOCOOH + NAD+ + CoASH = R1R2CHCO-S-CoA + NADH + CO2, component E1 (EC 1.2.4.4, branched-chain keto acid dehydrogenase), component E2 (no EC number, branched-chain acyltransferase), component E3 (EC 1.8.1.4, dihydrolipoamide dehydrogenase), partial reactions catalyzed by the multienzyme complex: 1. R1R2CHCOCOOH + E1-(thiamine diphosphate) = E1-(thiamine diphosphate)-COHCHR1R2 + CO2, 2. E1-(thiamine diphosphate)-COHCHR1R2 + lipoyl-E2 = R1R2CHCO-SCoA + dihydrolipoyl-E2, 4. dihydrolipoyl-E2 + NAD+ = lipoyl-E2 + NADH
NAD+
-
Km: 0.109 mM in the reaction with 4-methyl-2-oxopentanoate, Km: 0.126 mM in the reaction with 3-methyl-2-oxobutanoate, Km: 0.101 mM in the reaction with DL-3-methyl-2-oxobutanoate
NADH
Clostridium difficile
-, Q5U922
-
thiamine diphosphate
Q99PU6
-
thiamine diphosphate
-
bound to E1b component, binding kinetics, wild-type and mutant E1b components
thiamine diphosphate
-
bound to component E1, heterotetrameric cofactor binding fold, cofactor binding prevents phosphorylation of E1b and inactivates it by inducing a disorder-to-order transition of the conserved phosphorylation loop carrying 2 phosphorylation sites Ser292alpha andSer302alpha, cross-talk between thiamine diphosphate and the phosphorylation loop conformation as a feed-forward switch for th complex reaction
thiamine diphosphate
-
bound to complex component E1, involved in substrate recognition
thiamine diphosphate
-
bound to E1b component, dissociation constants of recombinant wild-type and mutant E1b components
thiamine diphosphate
-
-
thiamine diphosphate
-
dependent
additional information
Clostridium difficile
-, Q5U922
NADPH does not serve as a cosubstrate
-
METALS and IONS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
Ca2+
-
required
Mg2+
-
required
Mg2+
-
Km: 0.0042 mM in the reaction with 4-methyl-2-oxopentanoate; required
Mg2+
-
required
Mg2+
-
required
Mg2+
Q99PU6
-
Mg2+
-
-
Mg2+
-
required for the binding of cofactor thiamine diphosphate to component E1b, Mn2+ can substitute
Mg2+
-
required
phosphate
-
required
INHIBITORS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
2-chloro-4-methylpentanoate
-
inhibits component E1, modifies a histidine side chain
2-chloroisocaproate
-
-
2-Oxopentanoate
-
-
3-methyl-2-oxobutanoate
-
substrate inhibition
3-methyl-2-oxopentanoate
-
-
3-methylbutanoyl-CoA
-
-
3-methylbutanoyl-CoA
-
competitive with CoA
4-(2-Thienyl)-2-oxo-3-butenoate
-
-
4-(3-Thienyl)-2-oxo-3-butenoate
-
non-competitive
4-(3-Thienyl)-2-oxo-3-butenoate
-
-
4-methyl-2-oxopentanoate
-
substrate inhibition
4-methyl-2-oxopentanoate
-
-
alpha-Ketoisocaproate
-
allosteric inhibition, also by other branched-chain keto acids, although they are less effective as compared to alpha-ketoisocaproate
ATP
-
time-dependent inactivation of wild-type enzyme and mutant proteins S303A, S303E, with mutation in the alpha-subunit
cinnamylpyruvate
-
non-competitive
cinnamylpyruvate
-
-
Clofibrate
-
-
D-3-methyl-2-oxopentanoate
-
substrate inhibition
Furfurylidenepyruvate
-
competitive
Furfurylidenepyruvate
-
-
isobutanoyl-CoA
-
0.2 mM, 48% inhibition
isopentanoyl-CoA
-
0.2 mM. 56% inhibition
isopentanoyl-CoA
-
-
L-3-Methyl-2-oxopentanoate
-
substrate inhibition
microRNA 29a
-
total BCKD activity decreases over a 6-day period following a single transfection
-
NADH
-
0.1 mM, 44% inhibition
NADH
-
competitive with NAD+
NADH
-
active dephosphorylated BCKD, allosteric inhibition
Skeletal muscle factor
-
activity from liver, kidney and brains
-
microRNA 29b
-
total BCKD activity decreases over a 6-day period following a single transfection, is targeted to the mRNA for the dihydrolipoamide branched chain acyltransferase component of BCKD and prevents translation when bound
-
additional information
-
amount of E2 subunit protein decreases in E2-siRNA transfected cells
-
additional information
-
inhibited by phosphorylation, allosteric inhibition by CoA esters that arise during branched-chain amino acid catabolism
-
additional information
-
branched-chain alpha-keto acid dehydrogenase overall activity is nullified at 50% phosphorylation of E1b
-
ACTIVATING COMPOUND
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
Activator protein
-
a protein in rat liver and kidney mitochondria that reactivates phosphorylated branched-chain complex without dephosphorylation
-
alpha-Chloroisocaproate
-
activation of the enzyme complex in intact cell and tissue preparations
alpha-Chloroisocaproate
-
activates through release of branched-chain alpha-keto acid dehydrogenase kinase from the BCKD complex
alpha-Chloroisocaproate
-
-
alpha-Ketoisocaproate
-
activates through release of branched-chain alpha-keto acid dehydrogenase kinase from the BCKD complex
alpha-Ketoisocaproate
-
promotes dissociation of the BCKDH kinase from the BCKDH complex, consistent with activation of BCKDH complex
alpha-ketoisovalerate
-
activates through release of branched-chain alpha-keto acid dehydrogenase kinase from the BCKD complex
bezafibrate
-
i.e. 2-[4-[2-(4-chlorobenzamido)ethyl]phenoxy]-2-methylpropanoic acid. In rats treated with 5, 10, 20 mg/kg bezafibrate mean enzyme actual activity is 1.9, 2.9, and 4.3fold higher than in the control group, respectively. Enzymatic total activity increases by 1.3 and 1.6fold in rats treated with 10 and 20 mg/kg bezafibrate
L-Val
-
activates, when ommited from the assay mixture the rate of NAD+ reduction decreases to 41% of the rate of the complete system
L-Val
-
no activation
Skeletal muscle factor
-
stimulates enzyme from liver
-
thiamine
-
thiamine increases the specific activity of the human liver enzyme complex
thiamine diphosphate
-
the multienzyme complex catalyzes a thiamine diphosphate- and Mg2+-dependent oxidative decarboxylation of branched-chain keto acids with the formation of branched-chain acyl-CoA and reduction of NAD+ to NADH: R1R2CHCOCOOH + NAD+ + CoASH = R1R2CHCO-S-CoA + NADH + CO2, component E1 (EC 1.2.4.4, branched-chain keto acid dehydrogenase), component E2 (no EC number, branched-chain acyltransferase), component E3 (EC 1.8.1.4, dihydrolipoamide dehydrogenase), partial reactions catalyzed by the multienzyme complex: 1. R1R2CHCOCOOH + E1-(thiamine diphosphate) = E1-(thiamine diphosphate)-COHCHR1R2 + CO2, 2. E1-(thiamine diphosphate)-COHCHR1R2 + lipoyl-E2 = R1R2CHCO-SCoA + dihydrolipoyl-E2, 4. dihydrolipoyl-E2 + NAD+ = lipoyl-E2 + NADH
thiamine diphosphate
-
-
thiamine diphosphate
-
Km: 0.00035 mM in the reaction with 4-methyl-2-oxopentanoate
thiamine diphosphate
-
required
thiamine diphosphate
-
required
thiamine diphosphate
-
-
thiamine diphosphate
-
required
thiamine diphosphate
-
-
thiamine diphosphate
-
Km: 0.0012 mM in the reaction with 3-methyl-2-oxobutanoate
thiamine diphosphate
-
-
thiamine diphosphate
-
-
thiamine diphosphate
-
-
thiamine diphosphate
-
-
thiamine diphosphate
-
-
tumor necrosis factor-alpha
-
0.025 or 0.5 mg per kg body weight elevate the activity state of BCKDH complex from 22% to 69% and 86%, respectively, decrease in the bound form of BCKDH kinase is involved in the mechanism responsible for tumor necrosis factor-alpha induced activation of the BCKDH complex; activates the multienzyme complex about 4fold at 0.05 mg/kg body weight 4 h prior to slaughtering, reduces the amount of phosphorylated E1b component
-
tumor necrosis factor-alpha
-
promotes dissociation of the BCKDH kinase from the BCKDH complex in rat liver, resulting in activation of the BCKDH complex
-
Lipoamide
-
the multienzyme complex catalyzes a thiamine diphosphate- and Mg2+-dependent oxidative decarboxylation of branched-chain keto acids with the formation of branched-chain acyl-CoA and reduction of NAD+ to NADH: R1R2CHCOCOOH + NAD+ + CoASH = R1R2CHCO-S-CoA + NADH + CO2, component E1 (EC 1.2.4.4, branched-chain keto acid dehydrogenase), component E2 (no EC number, branched-chain acyltransferase), component E3 (EC 1.8.1.4, dihydrolipoamide dehydrogenase), partial reactions catalyzed by the multienzyme complex: 1. R1R2CHCOCOOH + E1-(thiamine diphosphate) = E1-(thiamine diphosphate)-COHCHR1R2 + CO2, 2. E1-(thiamine diphosphate)-COHCHR1R2 + lipoyl-E2 = R1R2CHCO-SCoA + dihydrolipoyl-E2, 4. dihydrolipoyl-E2 + NAD+ = lipoyl-E2 + NADH
additional information
-
clofibric acid and thiamine diphosphate have no effect on the protein-protein interaction between branched-chain alpha-keto acid dehydrogenase kinase and BCKD complex
-
additional information
-
activated by dephosphorylation
-
additional information
-
endurance exercise activates the BCKDH complex
-
KM VALUE [mM]
KM VALUE [mM] Maximum
SUBSTRATE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
2.8
-
(R)-2-hydroxyisocaproate
Clostridium difficile
-, Q5U922
-
0.0133
-
2-oxo-4-methylthiobutanoate
-
-
0.028
-
2-oxo-isovalerate
-
E1b component mutant S302Aalpha
0.048
-
2-oxo-isovalerate
-
wild-type E1b component
0.05
-
2-oxo-isovalerate
-
recombinant wild-type component E1b, and mutant D295Aalpha, pH 7.5, 22C
0.059
-
2-oxo-isovalerate
-
recombinant wild-type E1b component, pH 7.5, 22C
0.118
-
2-oxo-isovalerate
-
recombinant E1b component mutant H291Nalpha, pH 7.5, 22C
0.119
-
2-oxo-isovalerate
-
wild type enzyme
0.193
-
2-oxo-isovalerate
-
E1b component mutant S292Nalpha
0.203
-
2-oxo-isovalerate
-
recombinant E1b component mutant H291Qalpha, pH 7.5, 22C
0.206
-
2-oxo-isovalerate
-
recombinant E1b component mutant H291Aalpha, pH 7.5, 22C
0.23
-
2-oxo-isovalerate
-
recombinant component E1b mutant R301Aalpha, pH 7.5, 22C
0.25
-
2-oxo-isovalerate
-
recombinant component E1b mutant Y300Falpha, pH 7.5, 22C
0.34
-
2-oxo-isovalerate
-
recombinant component E1b mutant Y300Aalpha, pH 7.5, 22C
2.33
-
2-oxo-isovalerate
-
recombinant component E1b mutant R287Aalpha, pH 7.5, 22C
4.38
-
2-oxo-isovalerate
-
E1b component mutant S292Dalpha
0.0075
-
2-oxobutanoate
-
-
0.0258
-
2-oxobutanoate
-
-
0.056
-
2-oxobutanoate
-
-
0.29
-
2-oxoglutarate
-
-
2.5
-
2-oxoglutarate
-
-
5
-
2-Oxohexanoate
Clostridium difficile
-, Q5U922
-
0.068
-
2-oxoisocaproate
Clostridium difficile
-, Q5U922
-
0.084
-
2-Oxopentanoate
Clostridium difficile
-, Q5U922
-
0.00067
-
3-methyl-2-oxobutanoate
-
-
0.0106
-
3-methyl-2-oxobutanoate
-
-
0.011
-
3-methyl-2-oxobutanoate
-
-
0.013
-
3-methyl-2-oxobutanoate
-
-
0.0156
-
3-methyl-2-oxobutanoate
-
-
0.028
-
3-methyl-2-oxobutanoate
-
-
0.0372
-
3-methyl-2-oxobutanoate
-
-
0.04
-
3-methyl-2-oxobutanoate
-
-
0.056
-
3-methyl-2-oxobutanoate
-
wild-type enzyme and mutant enzyme D297A
0.058
-
3-methyl-2-oxobutanoate
-
mutant enzyme T294A
0.059
-
3-methyl-2-oxobutanoate
-
mutant enzyme G290A and S298A
0.062
-
3-methyl-2-oxobutanoate
-
mutant enzyme I289A and H291A
0.064
-
3-methyl-2-oxobutanoate
-
mutant enzyme S295A
0.091
-
3-methyl-2-oxobutanoate
-
-
0.213
-
3-methyl-2-oxobutanoate
-
-
0.46
-
3-methyl-2-oxobutanoate
-
-
0.568
-
3-methyl-2-oxobutanoate
-
mutant enzyme S293A
0.01
-
3-methyl-2-oxopentanoate
-
-
0.014
-
3-methyl-2-oxopentanoate
-
-
0.0199
-
3-methyl-2-oxopentanoate
-
-
0.0219
-
3-methyl-2-oxopentanoate
-
-
0.037
-
3-methyl-2-oxopentanoate
-
-
0.25
-
3-methyl-2-oxopentanoate
-
-
0.0062
-
4-methyl-2-oxopentanoate
-
-
0.0087
-
4-methyl-2-oxopentanoate
-
-
0.011
-
4-methyl-2-oxopentanoate
-
-
0.0146
-
4-methyl-2-oxopentanoate
-
-
0.015
-
4-methyl-2-oxopentanoate
-
-
0.0215
-
4-methyl-2-oxopentanoate
-
-
0.0218
-
4-methyl-2-oxopentanoate
-
-
0.05
-
4-methyl-2-oxopentanoate
-
-
0.2
-
4-methyl-2-oxopentanoate
-
-
0.033
-
coenzyme A
-
-
0.06
-
coenzyme A
-
-
0.0105
-
DL-3-methyl-2-oxopentanoate
-
-
0.03
-
NAD+
-
-
0.0387
-
NAD+
-
reaction with DL-3-methyl-2-oxopentanoate
0.0395
-
NAD+
-
reaction with 3-methyl-2-oxobutanoate
0.0423
-
NAD+
-
reaction with 4-methyl-2-oxopentanoate
0.056
-
NAD+
Clostridium difficile
-, Q5U922
-
0.12
-
NAD+
-
reaction with 3-methyl-2-oxobutanoate
0.031
-
NADH
Clostridium difficile
-, Q5U922
-
10
-
phenylpyruvate
Clostridium difficile
-, Q5U922
-
0.173
-
pyruvate
-
-
0.715
-
pyruvate
-
-
0.82
-
pyruvate
-
-
0.97
-
pyruvate
-
-
1
-
pyruvate
-
-
2.2
-
pyruvate
-
-
0.00055
-
thiamine diphosphate
-
recombinant wild-type E1b component, pH 7.5, 22C
0.0014
-
thiamine diphosphate
-
recombinant E1b component mutant H291Nalpha, pH 7.5, 22C
0.007
-
thiamine diphosphate
-
recombinant wild-type component E1b, pH 7.5, 22C
0.009
-
thiamine diphosphate
-
recombinant E1b component mutant H291Qalpha, pH 7.5, 22C
0.017
-
thiamine diphosphate
-
recombinant component E1b mutant D295Aalpha, pH 7.5, 22C
0.024
-
thiamine diphosphate
-
recombinant E1b component mutant H291Aalpha, pH 7.5, 22C
0.024
-
thiamine diphosphate
-
recombinant component E1b mutant R287Aalpha, pH 7.5, 22C
0.029
-
thiamine diphosphate
-
recombinant component E1b mutants R301Aalpha and Y300Falpha, pH 7.5, 22C
0.04
-
thiamine diphosphate
-
recombinant component E1b mutant Y300Aalpha, pH 7.5, 22C
0.0172
-
DL-3-methyl-2-oxopentanoate
-
-
additional information
-
additional information
-
-
-
additional information
-
additional information
Q8QHL7
-
-
additional information
-
additional information
Q99PU6
-
-
additional information
-
additional information
-
binding between E1b, wild-type and mutant, and E2b/lipoic acid-bearing domain components and thermodynamics, overall reaction kinetics, overview
-
additional information
-
additional information
-
kinetics of the overall reaction, thermodynamics and dissociation constants of interaction between component E1b and the lipoic acid-bearing domain of component E2b
-
additional information
-
additional information
-
kinetics, wild-type and mutant E1b components
-
TURNOVER NUMBER [1/s]
TURNOVER NUMBER MAXIMUM[1/s]
SUBSTRATE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
51
-
(R)-2-hydroxyisocaproate
Clostridium difficile
-, Q5U922
-
0.195
-
2-oxo-isovalerate
-
recombinant wild-type component E1b, pH 7.5, 22C
0.36
-
2-oxo-isovalerate
-
recombinant component E1b mutant Y300Aalpha, pH 7.5, 22C
0.38
-
2-oxo-isovalerate
-
recombinant component E1b mutant R287Aalpha, pH 7.5, 22C
0.41
-
2-oxo-isovalerate
-
recombinant component E1b mutant R301Aalpha, pH 7.5, 22C
0.485
-
2-oxo-isovalerate
-
recombinant component E1b mutant D295Aalpha, pH 7.5, 22C
0.49
-
2-oxo-isovalerate
-
recombinant E1b component mutant H291Qalpha, pH 7.5, 22C
0.57
-
2-oxo-isovalerate
-
recombinant component E1b mutant Y300Falpha, pH 7.5, 22C
0.58
-
2-oxo-isovalerate
-
recombinant E1b component mutant H291Aalpha, pH 7.5, 22C
0.58
-
2-oxo-isovalerate
-
E1b component mutant S292Dalpha
0.67
-
2-oxo-isovalerate
-
recombinant E1b component mutant H291Nalpha, pH 7.5, 22C
2.18
-
2-oxo-isovalerate
-
E1b component mutant S302Aalpha
3.3
-
2-oxo-isovalerate
-
wild-type E1b component
3.92
-
2-oxo-isovalerate
-
E1b component mutant S292Nalpha
8.65
-
2-oxo-isovalerate
-
recombinant wild-type E1b component, pH 7.5, 22C
9.4
-
2-oxo-isovalerate
-
wild type enzyme
33
-
2-Oxohexanoate
Clostridium difficile
-, Q5U922
-
31
-
2-oxoisocaproate
Clostridium difficile
-, Q5U922
-
22
-
2-Oxopentanoate
Clostridium difficile
-, Q5U922
-
0.1983
-
alpha-ketoisovaleric acid
-
wild-type
2.85
-
alpha-ketoisovaleric acid
-
hE1b-Tyr113Phe mutant
25
-
NAD+
Clostridium difficile
-, Q5U922
-
49
-
NADH
Clostridium difficile
-, Q5U922
-
63
-
phenylpyruvate
Clostridium difficile
-, Q5U922
-
0.197
-
thiamine diphosphate
-
recombinant wild-type component E1b, pH 7.5, 22C
0.31
-
thiamine diphosphate
-
recombinant component E1b mutant Y300Aalpha, pH 7.5, 22C
0.39
-
thiamine diphosphate
-
recombinant component E1b mutant R287Aalpha, pH 7.5, 22C
0.41
-
thiamine diphosphate
-
recombinant E1b component mutant H291Qalpha, pH 7.5, 22C
0.42
-
thiamine diphosphate
-
recombinant component E1b mutants R301Aalpha and D295Aalpha, pH 7.5, 22C
0.53
-
thiamine diphosphate
-
recombinant component E1b mutant Y300Falpha, pH 7.5, 22C
0.6
-
thiamine diphosphate
-
recombinant E1b component mutant H291Nalpha, pH 7.5, 22C
0.73
-
thiamine diphosphate
-
recombinant E1b component mutant H291Aalpha, pH 7.5, 22C
6.38
-
thiamine diphosphate
-
recombinant wild-type E1b component, pH 7.5, 22C
Ki VALUE [mM]
Ki VALUE [mM] Maximum
INHIBITOR
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
0.15
-
4-(3-Thienyl)-2-oxo-3-butenoate
-
-
0.5
-
cinnamylpyruvate
-
-
0.0005
-
Furfurylidenepyruvate
-
-
0.0082
-
isovaleryl-CoA
-
reaction with 3-methyl-2-oxobutanoate
0.0101
-
isovaleryl-CoA
-
reaction with DL-3-methyl-2-oxopentanoate
0.0177
-
NADH
-
reaction with 3-methyl-2-oxobutanoate
0.018
-
NADH
-
reaction with 4-methyl-2-oxopentanoate
0.023
-
NADH
-
reaction with DL-3-methyl-2-oxopentanoate
0.0136
-
isovaleryl-CoA
-
reaction with 4-methyl-2-oxopentanoate
additional information
-
additional information
-
-
-
SPECIFIC ACTIVITY [µmol/min/mg]
SPECIFIC ACTIVITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
0.0582
-
-
-
3.13
-
Q8QHL7
purified branched-chain alpha-keto acid dehydrogenase multienzyme complex, substrate 2-oxo-isovalerate
5.5
-
-
multienzyme complex
8.8
-
-
multienzyme complex
12
-
-
-
38
-
-
E1 component expressed in Escherichia coli
additional information
-
-
-
additional information
-
-
assay method
additional information
-
-
-
additional information
-
-
-
additional information
-
Q99PU6
-
additional information
-
-
-
additional information
-
-
decarboxylation activity, 30C
pH OPTIMUM
pH MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
6.8
7.4
-
-
7.5
-
-
assay at
7.5
-
-
assay at
TEMPERATURE OPTIMUM
TEMPERATURE OPTIMUM MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
22
-
-
assay at
30
-
-
assay at
SOURCE TISSUE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
SOURCE
-
fetal and maternal
Manually annotated by BRENDA team
-
only a minor proportion of branched-chain 2-oxoacid dehydrogenase complex is active in mitochondria freshly prepared from rat heart
Manually annotated by BRENDA team
-
lowest activity
Manually annotated by BRENDA team
-
fetal and maternal
Manually annotated by BRENDA team
-
activity increases when plants are placed in the dark, expression is strongly associated with the progression of leaf senescence
Manually annotated by BRENDA team
-
elevated in tumour-bearing animals
Manually annotated by BRENDA team
-
fetal and maternal
Manually annotated by BRENDA team
-
elevated in tumour-bearing animals
Manually annotated by BRENDA team
-
fetal and maternal; skeletal muscle
Manually annotated by BRENDA team
-
fetal and maternal
Manually annotated by BRENDA team
-
highest activity
Manually annotated by BRENDA team
additional information
-
not detected in astrocytes and Bergmann glia cells
Manually annotated by BRENDA team
PDB
SCOP
CATH
ORGANISM
Thermoplasma acidophilum (strain ATCC 25905 / DSM 1728 / JCM 9062 / NBRC 15155 / AMRC-C165)
Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579)
Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579)
Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579)
Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579)
MOLECULAR WEIGHT
MOLECULAR WEIGHT MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
36000
-
Clostridium difficile
-, Q5U922
gel filtration
46270
-
-
unlipoylated enzyme, mass spectrometric analysis
46460
-
-
lipoylated enzyme, mass spectrometric analysis
79400
-
-
gel filtration
154000
-
-
E1, heart
160000
-
-
wild-type enzyme and mutant enzymes S293E, S293A, S303A and S293E/S303E, gel filtration
167000
-
-
E1 component, equilibrium sedimentation
172000
-
-
equilibrium sedimentation
190000
-
-
E1 component, gel filtration
190000
-
-
E1 component, gel filtration
additional information
-
-
MW of the holocomplex from ox liver is 275000 Da
additional information
-
-
the MW of the holocomplex of rabbit liver is higher than 2000000 Da
additional information
-
-
-
additional information
-
-
MW of the multienzyme complex is 2000000 Da, determined by sucrose density gradient centrifugation
additional information
-
-
MW of the multienzyme complex is 2000000 Da, determined by gel filtration
additional information
-
-
MW of the multienzyme complex of bovine heart is 8500000 Da; the MW of the multienzyme complex of bovine kidney is 3200000 Da
SUBUNITS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
24mer
-
E2 component
?
-
alphax,betax, x * 46500 + x * 38500, SDS-PAGE
?
-
alphax,betax, x * 478000 + x * 38000, SDS-PAGE
?
Q8QHL7
x * 54000, E2 component, SDS-PAGE, x * 47364, E2, sequence calculation, x * 45000, E1 alpha-subunit, SDS-PAGE, x * 36000, E1 beta-subunit, SDS-PAGE
?
Q99PU6
x * 52000, E2 component, SDS-PAGE, x * 45000, E1 alpha-subunit, SDS-PAGE, x * 36000, E1 beta-subunit, SDS-PAGE
heterotetramer
-
x-ray crystallography
homotetramer
-
4 * 19850, gel filtration; 4 * 20000, SDS-PAGE
tetramer
-
alpha2,beta2, 2 * 46000 + 2 * 35000, enzyme from kidney, SDS-PAGE; alpha2,beta2, 2 * 46000 + 2 * 35000, enzyme from liver, SDS-PAGE
tetramer
-
alpha2,beta2, 2 * 47000 + 2 * 37000, SDS-PAGE
tetramer
-
alpha2,beta2, 2 * 46000 + 2 * 37000, SDS-PAGE
tetramer
-
alpha2,beta2, 2 * 46000 + 2 * 35000, enzyme from kidney, SDS-PAGE
tetramer
-
alpha2,beta2, MW of alpha is 45000 Da, expression of bkdA2 yields the 39000 Da form and the 37000 Da form of the beta-subunit, both forms of the E1 beta-subunit are produced in Pseudomonas putida, only the 39000 Da protein is produced in Escherichia coli, SDS-PAGE
tetramer
-
alpha2,beta2, 2 * 45500 + 2 * 37500, wild-type enzyme, SDS-PAGE
tetramer
-
component E1, organized in alpha2beta2-structure
tetramer
-
E1 component
tetramer
-
alpha2,beta2, 2 * 41000 + 2 * 36000, heart enzyme, SDS-PAGE; alpha2,beta2, 2 * 46000 + 2 * 35000, enzyme from kidney, SDS-PAGE
monomer
Clostridium difficile
-, Q5U922
1 * 37000, SDS-PAGE, 1 * 36500, sequence analysis
additional information
-
lipoamide dehydrogenase component of the holoenzyme complex is a dimer, the E2 component is composed of 24 subunits
additional information
-
MW of the alpha subunit of the E1 component is 44394 Da, determined by SDS-PAGE
additional information
-
Y368C-alpha and T265R-alpha: missense mutation that cause the occurence of both alpha2beta2 tetramers and lower molecular weight species; Y393N-alpha and F364C-alpha: E1alpha-missense mutation that causes the occurence of exclusively alpha,beta dimers
additional information
Q8QHL7
E1 is a tetramer, E2 is composed of 3 domains, one of which is the lipoic acid-bearing domain LBD, the E2 dihydrolipoyl transacylase subunit is divided into different domains connected by inter-domain segments, overview
additional information
-
structure analysis, folding kinetics of the lipoic acid-bearing domain of enzyme complex component E2, a reversible 2-step mechanism for interconversion of the enzyme from native to denatured state without stable or kinetic intermediates, overview
additional information
-
lipoic acid-bearing domain of complex component E2: NMR secondary structure determination and analysis, a flattened beta-barrel formed by two 4-stranded antiparallel beta-sheets, loops connecting the beta-strands, tertiary fold, structure dynamics, complex component E2 structure, overview
additional information
-
the lipoic acid-bearing domain LBD, amino acid residues 1-84, is part of the E2b complex component, which is part of the the branched-chain alpha-ketoacid dehydrogenase multienzyme complex BCKD
additional information
-
E2 component is important for conformational stability of the branched chain alpha-ketoacid dehydrogenase multienzyme complex underlying the folding of the small beta-barrel of lipoic acid-bearing domain, overview, a reversible 2-step mechanism for interconversion of the enzyme from native to denatured state without stable or kinetic intermediates
additional information
-
E1b component, analysis of structure-function-relationship, overview
additional information
-
the multienzyme complex from bovine heart contains 4 times E1, 60 times E2 and 2 times E3
POSTTRANSLATIONAL MODIFICATION
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
phosphoprotein
-
branched-chain alpha-ketoacid dehydrogenase multienzyme complex BCKDC which is regulated by phosphorylation of component E1b, residue Ser292 of the alpha-domain, the phosphorylated recombinant E1b component shows highly reduced activity compared to the nonphosphorylated one
additional information
-
limited proteolytic analysis of E1b component, overview
Crystallization/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
20-25 mg/ml wild-type or recombinant His-tagged E1b component in 50 mM HEPES, pH 7.5, 0.25 M KCl, 0.5 mM PMSF, 1 mM benzamidine, 20 mM DTT, 5% v/v glycerol, vapour diffusion method, 20C, mixing with equal volume of well solution containing 1.4-1.6 M ammonium sulfate, 0.1 M sodium citrate, pH 5.8, 20 mM 2-mercaptoethanol, 4 mM MgCl2 or MnCl2, 4 mM thiamine diphosphate, maximal size after 10 day after microseeding, cryoprotection by well solution with 20% v/v glycerol, X-ray diffraction structure determination and analysis at 1.85-2.25 A resolution
-
crystals of E1b grown in the absence and presence of substrates at 22C via the vapor-diffusion method, key tyrosine residue in the E1b active site, functions as a conformational switch to reduce the reactivity of the thiamin diphosphate cofactor, the tyrosine switch further remodels an E1b loop region to promote E1b binding to E2b
-
purified wild-type and C-terminally His-tagged recombinant E1b component and mutants, 22C, hanging drop vapour diffusion method, Mg2+ or Mn2+, X-ray diffraction structure determination and analysis at 1.8 A resolution
-
crystallization of 4 forms of complex component E1: 1. E1 apoenzyme, 2. E1 holoenzyme, 3. E1 holoenzyme in complex with substrate analogue 4-methylpentanoate, 4. E1 holoenzyme in complex with substrate 4-methyl-2-oxopentanoate, hanging drop vapour diffusion method, 18C, 0.002 ml 10 mg/ml purified recombinant protein in 20 mM Tris-HCl, pH 8.0, 150 mM NaCl, 1 mM DTT, with equal volume of 0.002 ml of reservoir solution containing 0.7 M lithium sulfate, 60 mM sodium citrate, pH 5.6, against 0.4 ml reservoir solution, a few days, X-ray diffraction structure determination and analysis at 1.9-2.4 A resolution
-
TEMPERATURE STABILITY
TEMPERATURE STABILITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
50
-
-
20 min, about 85% loss of activity without thiamin diphosphate. 20 min, about 65% loss of activity in presence of 0.2 mM thiamin diphosphate
additional information
-
-
thermal and cold denaturation kinetics of lipoic acid-bearing domain
GENERAL STABILITY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
when saturated with thiamin diphosphate, the multienzyme complex is more stable to heat and chymotrypsin inactivation
-
maximum solubilization with minimum inactivation at 44 mM perchlorate carefully timed for 13 min
-
DTT stabilizes
Q99PU6
STORAGE STABILITY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
-20C, after concentration and dialysis into 50 mM Tris-HCl buffer, 0.1 mM EDTA, 0.1 mM EGTA, 1 mM benzamidine, 1 mM PMSF, 1 mM DTT, pH 7.3, multienzyme complex is stable for at least 2 months
-
-70C, enzyme complex is stable for more than 8 months
-
-70C, multienzyme complex is stable for at least 2 years
-
-80C, Tris-HCl buffer, pH 8.0, 2 months
Clostridium difficile
-, Q5U922
0C, glycerol buffer, 20% loss of activity after 24 h
-
-70C, 10 mM Tris-HC1, pH 8.0, containing 0.01 mM EDTA, 0.2 M NaCI, 0.005% (v/v) 2-mercaptoethanol, and 50% (v/v) glycerol, 2 years, remains active
-
0-5C, rapid loss of 20-30% of the activity, then stable for 3-4 months
-
-70C, 50 mM potassium phosphate buffer, pH 7.4, 0.1 mM EDTA, 0.2 mM thiamine diphosphate, 0.2 mM phenylmethylsulfonyl fluoride, stable for at least 3 weeks
-
Purification/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
multienzyme complex
-
partial
-
recombinant Strep tag II fusion protein purified to homogeneity by one-step affinity chromatography
Clostridium difficile
-, Q5U922
by Ni-NTA affinity chromatography
-
His Trap HP column chromatography and Strep-Tactin Superflow gravity column chromatography
-
recombinant C-terminally His-tagged lipoic acid-bearing domain LBD by nickel affinity chromatography
-
recombinant His-tagged lipoic acid-bearing domain of enzyme complex component E2 by nickel affinity chromatography and gel filtration to over 95% purity
-
recombinant lipoic acid-bearing domain of complex component E2 from Escherichia coli strain BL21(DE3) as His-tagged protein by nickel affinity chromatography
-
branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKADH, consisting of 3 subunits/components E1-E3, from liver mitochondria, isolation of the complex components E1, E2, and E3
Q8QHL7
multienzyme complex
-
multienzyme complex
-
DEAE-Sepharose CL-6B column chromatography and heparin-Sepharose CL-6B column chromatography
-
E1 component, recombinant enzyme
-
multienzyme complex
-
enzyme complex components E1 and E2 from liver mitochondria
Q99PU6
hydrophobic interaction chromatography on phenyl-Sepharose; multienzyme complex
-
multienzyme complex
-
multienzyme complex; partial
-
His-Bind affinity chromatography and Q-Sepharose Hi-Trap column chromatography
-
recombinant alpha- and beta-subunits of component E1 from Escherichia coli
-
Cloned/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
beta-subunit
-
beta-subunit
-
into vector pASK-IBA7 and overexpressed in Escherichia coli BL21-CodonPlus(DE3)
Clostridium difficile
-, Q5U922
beta-subunit
-
expressed in Escherichia coli BL-21 cells
-
expression of C-terminally His-tagged lipoic acid-bearing domain LBD, amino acid residues 1-84 of E2b
-
expression of C-terminally His-tagged lipoic acid-bearing domain of enzyme complex component E2 with an extra methionine at the N-terminus and a glutamic acid and leucine at the C-terminus in Escherichia coli strain BL21(DE3)
-
expression of N-and C-terminally His6-tagged component E1b and mutants, and of C-terminally His-tagged lipoic acid-bearing domain, amino acid residues 1-84 of component E2b, in vitro lipoylation of the latter
-
expression of the lipoic acid-bearing domain of complex component E2 in Escherichia coli strain BL21(DE3) as His-tagged protein
-
DNA and amino acid sequence determination and analysis of E2
Q8QHL7
expressed in Escherichia coli strain DH5alpha
-
expression in Escherichia coli
-
expression in Pseudomonas putida and Escherichia coli; region containing the genes for the entire enzyme complex
-
expression of E1 component in Escherichia coli as a homotetramer, in Escherichia coli only one translational start site for E1beta is recognized and only the 39000 Da product is produced, in addition the N-terminal amino acid of the 39000 Da E1beta subunit is Met instead of Leu
-
overexpression of bacterial branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKDC, encoded by 4 genes, in Arabidopsis thaliana targeted to chloroplasts, about 7fold increased enzyme activity in the transgenic plants
-
region containing the genes for the entire enzyme complex
-
expressed in Escherichia coli BL21(DE3) cells and BL21(DE3)pLysS cells
-
expression of alpha- and beta-subunits of component E1 in Escherichia coli
-
EXPRESSION
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
donor hepatocytes expressing wild type BCKDH engrafted into intermediate maple syrup urine disease recipient liver, increase liver BCKDH activity. Hepatocyte transplantation increases liver BCKDH activity 14.36% of control activity
-
total BCKDC activity and protein abundance of E1alpha, E1beta, and E2 subunits are markedly lower in Otsuka Long-Evans Tokushima Fatty (OLETF) than in Long-Evans Tokushima Otsuka (LETO) rats at 8 and 25 weeks of age. In addition, hepatic BCKDC activity and protein amounts are significantly decreased in LETO rats aged 25 weeks than in LETO rats aged 8 weeks. In skeletal muscle, subunits E1beta and E2 proteins are significantly reduced in OLETF rats
-
mRNA expression is not upregulated by bezafibrate treatment
-
in skeletal muscle, subunits E1alpha protein is significantly reduced in OLETF rats
-
ENGINEERING
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
D108N
-
less thermostable than wild type enzyme
D200A
-
less thermostable than wild type enzyme
D200A/D108N
-
the mutant is defective in folding and assembly and as no detectable overall activity
D200N
-
less thermostable than wild type enzyme
D295A
-
site-directed mutagenesis of an alpha-subunit residue of component E1b, increased activity compared to the wild-type
E198Q/D200N
-
the mutant is defective in folding and assembly and as no detectable overall activity
F364C
-
E1alpha-missense mutation in type IA maple syrup urine disease that causes the occurence of exclusively alpha,beta dimers
H146A
-
site-directed mutagenesis, mutation of a beta'-subunit residue, no reductive acylation activity, low decarboxylation activity
H147N
-
site-directed mutagenesis, mutation of a beta'-subunit residue, no reductive acylation activity, low decarboxylation activity
H291A
-
site-directed mutagenesis, mutation of a alpha-subunit residue, highly reduced activity compared to the wild-type E1b component
H291N
-
site-directed mutagenesis, mutation of a alpha-subunit residue, highly reduced activity compared to the wild-type E1b component
R287A
-
site-directed mutagenesis of an alpha-subunit residue of component E1b, highly increased Km and reduced activity compared to the wild-type
R301A
-
site-directed mutagenesis of an alpha-subunit residue of component E1b, increased Km and reduced activity compared to the wild-type
S292D
-
site-directed mutagenesis, mutation of a alpha-subunit residue of complex component E1b, reduced activity compared to the wild-type E1b component
S292E
-
site-directed mutagenesis, mutation of a alpha-subunit residue of complex component E1b, highly reduced activity compared to the wild-type E1b component
S292N
-
site-directed mutagenesis, mutation of a alpha-subunit residue of complex component E1b, reduced activity compared to the wild-type E1b component
S292Q
-
site-directed mutagenesis, mutation of a alpha-subunit residue of complex component E1b, inactive mutant
S292Q
-
no activity
S302A
-
site-directed mutagenesis, mutation of a alpha-subunit residue of complex component E1b, increased activity compared to the wild-type E1b component
T265R
-
missense mutation in type IA maple syrup urine disease that causes the occurence of both alpha2beta2 tetramers and lower molecular weight species
Y300A
-
site-directed mutagenesis of an alpha-subunit residue of component E1b, increased Km and reduced activity compared to the wild-type
Y300F
-
site-directed mutagenesis of an alpha-subunit residue of component E1b, increased Km and reduced activity compared to the wild-type
Y368C
-
missense mutation in type IA maple syrup urine disease that causes the occurence of both alpha2beta2 tetramers and lower molecular weight species
S313A
-
twofold increase in Km-value but no change in turnover-number
S315A
-
mutation has no effect on Km-value or turnover-number
S319A
-
mutation has no effect on Km-value or turnover-number
D296A
-
inactive enzyme, no ability of component E1 apoenzyme to reconstitute with thiamine diphosphate
H292A
-
inactive enzyme, no binding of thiamine diphosphate
R288A
-
inactive enzyme, no detectable phosphorylation
S293A
-
mutation in the alpha-subunit, nearly 12fold increase in Km-value, no inactivation after incubation with ATP
S293A
-
10fold increased Km-value for 3-methyl-2-oxobutanoate, 2.8fold increased Km-value for 4-methyl-2-oxopentanoate, no change in Km-value for thiamine diphosphate
S293E
-
mutation in the alpha-subunit, completely inactive enzyme
S293E
-
no ability of the E1 apoenzyme to reconstitute with thiamine diphosphate
S293E/S303E
-
mutation in the alpha-subunit, no activity
S303A
-
mutation in the alpha-subunit, no effect upon enzyme activity
H291Q
-
site-directed mutagenesis, mutation of a alpha-subunit residue, highly reduced activity compared to the wild-type E1b component
additional information
-
missense mutation in E1b subunits that cause maple syrup urine disease: R114W-alpha, T166M-alpha, R220W-alpha. N222S-alpha. M64T-alpha. G204S-alpha. A208T-alpha. T265R-alpha, I281T-alpha, N126Y-beta, Q145K-alpha, H156R-beta, A209D-alpha, A240P-alpha. G245R-alpha, R252H-alpha, F364C-alpha, Y368C-alpha and Y393N-alpha
additional information
-
enzyme complex regulation by reversible phosphorylation is impaired in component E1b S292 and S302 mutants, no or residual acylation of the lipoic acid-bearing domain of component E2b, overview
additional information
-
hE1b-Tyr113Phe mutant, specifically affects the decarboxylation reaction, thiamine diphosphate appears hyperactive, is prone to paracatalytic inactivation
additional information
-
the hybrid E1b heterotetramer carrying one wild type, one S292Qalpha subunit, and two wild type beta subunits contains only one functional active site and exhibits nearly 40% of the wild type activity
Y393N
-
E1alpha-missense mutation in type IA maple syrup urine disease that causes the occurence of exclusively alpha,beta dimers
additional information
-
construction of transgenic Arabidopsis thaliana plants overexpressing the branched-chain alpha-keto acid dehydrogenase multienzyme complex BCKDC in chloroplasts via Agrobacterium tumefaciens transformation under control of the CaMV 35S promotor, accumulation of branched-chain acyl-CoAs and alteration of free amino acid composition in seeds, overview
S303E
-
mutation in the alpha-subunit, no effect upon enzyme activity
additional information
-
complete deletion of the bkdR open reading frame, produces fewer spores or the spores have reduced viability, is apparently not complemented in trans by the wild-type allele, is able to utilize leucine as sole carbon source and has no detectable growth defect, bkdR gene product acts as a repressor, rather than an activator of transcription
Renatured/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
denaturating of the lipoic acid-bearing domain of enzyme complex component E2 by 8 M urea, refolding by 10fold dilution, folding kinetics of the reversible 2-step mechanism
-
isothermal urea denaturation and refolding kinetics of lipoic acid-bearing domain, 2-step mechanism, overview
-
reconstitution of the active multienzyme complex with resolved components
Q8QHL7
APPLICATION
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
medicine
-
activation of the BCKDH complex appears responsible for the increase in branched-chain amino acid catabolism caused by exercise and liver cirrhosis, branched-chain amino acid administration improves protein turnover in humans with liver cirrhosis, suggesting that branched-chain amino acid supplements are appropriate for patients with liver cirrhosis, branched-chain amino acid administration in patients with acute liver failure, especially those with high serum branched-chain amino acid concentrations, may not be appropriate because of the likelihood of branched-chain amino acid overload
medicine
-
activation of the BCKDH complex appears responsible for the increase in branched-chain amino acid catabolism caused by exercise and liver cirrhosis, branched-chain amino acid administration improves protein turnover in rats with liver cirrhosis, suggesting that branched-chain amino acid supplements are appropriate for patients with liver cirrhosis
medicine
-
variations in the gene of branched-chain alpha-keto acid dehydrogenase are associated with the occurrence of premature ovarian failure
additional information
-
use of a microRNA to exert control on a metabolic pathway of amino acid catabolism
additional information
-
NMR techniques to determine the structure of hbSBD and dynamics of several truncated constructs from the E2 component, including hbLBD (residues 184), hbSBD (residues 111149), and a di-domain (hbDD) (residues 1166) comprising hbLBD, hbSBD and the interdomain linker, the presence of the interdomain linker restricts the motional freedom of the hbSBD more significantly than hbLBD, the linker region likely exists as a soft rod rather than a flexible string in solution
additional information
-
regulation of BCKD kinase expression by nutritional, hormonal, and pathological factors
additional information
-
activation of the translational regulators by leucine is partly regulated by the activity of BCKDH complex