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Enzyme Nomenclature
Information on EC 4.2.1.24 - porphobilinogen synthase
Word Map on EC 4.2.1.24
- 4.2.1.24
- erythrocyte
- heme
- hepatic
- zinc
- protoporphyrin
- urinary
-
poison
- renal
- porphyria
-
workers
- hemoglobin
-
intoxication
- catalase
-
drinking
- urine
- gsh
- deaminase
- anemia
-
tbars
-
uroporphyrinogen
- ferrochelatase
- succinylacetone
-
hematocrit
-
thiobarbituric
- tetrapyrrole
- cadmium
-
hematological
-
octamer
-
lead-exposed
-
lead-induced
-
delta-aminolaevulinic
-
diphenyl
- diselenide
-
occupationally
- tyrosinemia
-
smelter
-
erythropoietic
-
uroporphyrin
- coproporphyria
-
cutanea
- coproporphyrinogen
- tarda
- gallium
- medicine
-
arsenic-induced
-
proto
-
organoselenium
-
micrograms/100
-
corpuscular
-
porphyrinogenic
- environmental protection
- diagnostics
- analysis
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The expected taxonomic range for this enzyme is: Bacteria, Eukaryota, Archaea
topEC NUMBER 
COMMENTARY 
4.2.1.24
-
RECOMMENDED NAME
GeneOntology No.
porphobilinogen synthase
REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
2 5-aminolevulinate = porphobilinogen + 2 H2O
-
-
-
-
2 5-aminolevulinate = porphobilinogen + 2 H2O
requires an active Arg residue and the formation of a Schiff base between the enzyme and 5-aminolevulinate
-
2 5-aminolevulinate = porphobilinogen + 2 H2O
substrate is covalently bound through a Schiff base
-
2 5-aminolevulinate = porphobilinogen + 2 H2O
substrate is covalently bound through a Schiff base
-
2 5-aminolevulinate = porphobilinogen + 2 H2O
catalytic mechanism in which the C-C bond linking both substrates in the intermediate is formed before the C-N bond
-
2 5-aminolevulinate = porphobilinogen + 2 H2O
catalytic mechanism initiated by a C-C bond formation between A and P-side 5-aminolevulinic acid, followed by the formation of the intersubstrate Schiff base yielding the product porphobilinogen
-
2 5-aminolevulinate = porphobilinogen + 2 H2O
reaction mechanism involving asymmetric addition and cyclization of two 5-aminolevulinate molecules, modeling, detailed overview. The active site consists of several invariant residues, including two lysyl residues Lys210 and Lys263 that bind the two substrate moieties as Schiff bases, active site structure and substrate binding, overview. The intersubstrate C-N bond is formed first have a rate-limiting barrier that is lower than those in which the intersubstrate C-C bond is formed first
-
REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
elimination
-
-
of H2O, C-O bond clevage
-
PATHWAY
BRENDA Link
KEGG Link
MetaCyc Link
SYSTEMATIC NAME
IUBMB Comments
5-aminolevulinate hydro-lyase (adding 5-aminolevulinate and cyclizing; porphobilinogen-forming)
The enzyme catalyses the asymmetric condensation and cyclization of two 5-aminolevulinate molecules, which is the first common step in the biosynthesis of tetrapyrrole pigments such as porphyrin, chlorophyll, vitamin B12, siroheme, phycobilin, and cofactor F430. The enzyme is widespread, being essential in organisms that carry out respiration, photosynthesis, or methanogenesis. The enzymes from most organisms utilize metal ions (Zn2+, Mg2+, K+, and Na+) as cofactors that reside at multiple sites, including the active site and allosteric sites. Enzymes from archaea, yeast, and metazoa (including human) contain Zn2+ at the active site. In humans, the enzyme is a primary target for the environmental toxin Pb. The enzymes from some organisms utilize a dynamic equilibrium between architecturally distinct multimeric assemblies as a means for allosteric regulation.
CAS REGISTRY NUMBER
COMMENTARY
9036-37-7
-
ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
-
210684, 210686, 210687, 210690, 210696, 210701, 210702, 210703, 210706, 210708, 210709, 653399, 666966
-
-
the Plasmodium falciparum enzyme may account for about 10% of the total delta-aminolevulinate dehydratase activity in the parasite, the rest being accounted for by the host enzyme imported by the parasite
-
-
-
210685, 210687, 210688, 210689, 210691, 210694, 210698, 210699, 210708, 210724, 210733, 651009, 653997, 653998, 664549, 677436, 678572, 679258, 679261, 682908, 693344, 694568, 702882, 713748, 714758, 730290
-
-
GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
malfunction
metabolism
physiological function
malfunction
-
delta-aminolevulinic acid dehydratase-deficient porphyria is a rare enzymatic deficiency of the heme biosynthetic pathway
malfunction
-
delta-ALA-D activity is inhibited in diabetes mellitus, which can result in aminolevulinic acid accumulation that, under physiological relevant conditions, can have pro-oxidant effects. delta-ALA-D activity shows to be correlated with lipid profile indicating that disturbances in lipoproteins metabolism may affect the enzymatic activity
metabolism
-
delta-aminolevulinic acid dehydratase is involved in the heme biosynthetic pathway
physiological function
-
it is shown that autologous and allogeneic bone marrow transplantation are associated with oxidative stress and that delta-ALA-D activity is a reliable marker for oxidative stress in bone marrow transplantation patients
physiological function
-
delta-aminolevulinate dehydratase is a cytosolic sulfhydryl-containing enzyme that catalyzes the condensation of two molecules of aminolevulinic acid in order to form porphobilinogen, which is the precursor of heme, cytochromes and cobalamines. ALAD plays a role in proteasome S26 activity, which it increases by 75%, overview. The 26S proteasome, a protein complex formed by 32 subunits, performs multiple important proteolytic activities in the cell interacting with the ubiquitination system
physiological function
-
PBGS is a key enzyme in heme biosynthesis that catalyzes the formation of porphobilinogen from two 5-aminolevulinic acid molecules via formation of intersubstrate C-N and C-C bonds
physiological function
-
infection with Trypanosoma evansi is associated with haematocrit, serum levels of iron and zinc and lipid peroxidation. Increased activity of delta-ALA-D in blood occurs in response to the anaemia in remission as heme synthesis is enhanced, iron reduction has a negative correlation with the activity of delta-ALA-D
physiological function
-
infection with Trypanosoma evansi is associated with haematocrit, serum levels of iron and zinc and lipid peroxidation. Increased activity of delta-ALA-D in blood occurs in response to the anaemia in remission as heme synthesis is enhanced, iron reduction has a negative correlation with the activity of delta-ALA-D
-
SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
5-aminolevulinate
?
-
induction by 17beta-estradiol of 5-aminolevulinate
-
-
-
5-aminolevulinate
?
-
during erythropoiesis in chordates the enzyme functions as a part of the heme synthesizing machinery
-
-
-
5-aminolevulinate
?
-
second enzyme in the heme biosynthetic pathway
-
-
-
5-aminolevulinate
?
-
the second and rate-limiting enzyme of the heme-biosynthetic pathway
-
-
-
5-aminolevulinate
?
-
enzyme catalyzes the first common step in tetrapyrrole biosynthesis
-
-
-
5-aminolevulinate
?
enzyme catalyzes the first common step in tetrapyrrole biosynthesis
-
-
-
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
Acutodesmus obliquus
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
(3R)-5-aminolevulinate shows a significantly larger isotope effect than (3S)-5-aminolevulinate
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
(3R)-5-aminolevulinate shows a significantly larger isotope effect than (3S)-5-aminolevulinate
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
essential step in tetrapyrrole biosynthesis
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
the enzyme catalyzes the first common step in the biosynthesis of tetrapyrroles
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
the enzyme functions in the first common step in tetrapyrrole biosynthesis
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
incubations of erythrocytes for 24 h with glucose result in an increase of delta-ALA-D activity. Incubations of erythrocytes with 100 to 200 mM glucose for 48 h inhibit delta-ALA-D activity
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
the role of the enzyme may be confined to heme synthesis in the apicoplast that may not account for the total de novo heme biosynthesis in the parasite
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
porphobilinogen synthase catalyzes the first committed step of the tetrapyrrole biosynthesis pathway
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
enzymatic mechanism starts with formation of a C-C bond, linking C3 of the A-side 5-aminolevulinic acid to C4 of the P-side 5-aminolevulinic acid through an aldole addition
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
the enzyme catalyzes the third step of tetrapyrrole synthesis leading to the formation of heme and chlorophylls in plant tissues. In the light, both 5-aminolevulinate dehydratase activity, and protein level increases 3-4 times compared to the dark-control level. However, no change in the amount of related mRNA is observed. The apparent stability of the mRNA can be due to the abundant expression of a housekeeping gene, which shadows a related gene expressed in the light
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
the enzyme plays a rate-limiting role in heme biosynthesis of saccharomyces cerevisiae
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
-
-
?
5-aminolevulinic acid + 5-aminolevulinic acid
porphobilinogen + 2 H2O
-
-
-
-
?
5-aminolevulinic acid + 5-aminolevulinic acid
porphobilinogen + 2 H2O
-
-
-
-
?
5-aminolevulinic acid + 5-aminolevulinic acid
porphobilinogen + 2 H2O
-
-
-
-
?
5-aminolevulinic acid + 5-aminolevulinic acid
porphobilinogen + 2 H2O
-
-
-
-
?
additional information
?
-
-
the enzyme has a dual role: 1. as 5-aminolevulinate dehydatase, the second enzyme in the pathway of heme synthesis, 2. as CF-2 proteasome inhibitor
-
-
-
additional information
?
-
-
direct assay method development with incubation of erythrocyte lysate with the natural substrate, 5-aminolevulinate, followed by quantitative in situ conversion of porphobilinogen to its butyramide and mass spectrometric determination, overview. Using a carbonate buffer rather than phosphate causes nearly a 90% drop in activity and addition of zinc results in a further decrease by up to 35%
-
-
-
additional information
?
-
-
the enzyme stimulates renaturation of luciferase by hsp 70, a member of the heat shock protein 70kDa-family, up to 10fold
-
-
-
additional information
?
-
-
the enzyme stimulates renaturation of luciferase by hsp 70 up to 10fold
-
-
-
additional information
?
-
-
early enzyme of the tetrapyrrole biosynthesis pathway
-
-
-
NATURAL SUBSTRATES
NATURAL PRODUCTS
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
5-aminolevulinate
?
-
induction by 17beta-estradiol of 5-aminolevulinate
-
-
-
5-aminolevulinate
?
-
during erythropoiesis in chordates the enzyme functions as a part of the heme synthesizing machinery
-
-
-
5-aminolevulinate
?
-
second enzyme in the heme biosynthetic pathway
-
-
-
5-aminolevulinate
?
-
the second and rate-limiting enzyme of the heme-biosynthetic pathway
-
-
-
5-aminolevulinate
?
-
enzyme catalyzes the first common step in tetrapyrrole biosynthesis
-
-
-
5-aminolevulinate
?
Q59643
enzyme catalyzes the first common step in tetrapyrrole biosynthesis
-
-
-
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
essential step in tetrapyrrole biosynthesis
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
the enzyme catalyzes the first common step in the biosynthesis of tetrapyrroles
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
P13716
the enzyme functions in the first common step in tetrapyrrole biosynthesis
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
the role of the enzyme may be confined to heme synthesis in the apicoplast that may not account for the total de novo heme biosynthesis in the parasite
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
porphobilinogen synthase catalyzes the first committed step of the tetrapyrrole biosynthesis pathway
-
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
the enzyme catalyzes the third step of tetrapyrrole synthesis leading to the formation of heme and chlorophylls in plant tissues. In the light, both 5-aminolevulinate dehydratase activity, and protein level increases 3-4 times compared to the dark-control level. However, no change in the amount of related mRNA is observed. The apparent stability of the mRNA can be due to the abundant expression of a housekeeping gene, which shadows a related gene expressed in the light
-
?
5-aminolevulinate + 5-aminolevulinate
porphobilinogen + 2 H2O
-
the enzyme plays a rate-limiting role in heme biosynthesis of saccharomyces cerevisiae
-
?
additional information
?
-
-
the enzyme has a dual role: 1. as 5-aminolevulinate dehydatase, the second enzyme in the pathway of heme synthesis, 2. as CF-2 proteasome inhibitor
-
-
-
additional information
?
-
-
the enzyme stimulates renaturation of luciferase by hsp 70 up to 10fold
-
-
-
additional information
?
-
-
early enzyme of the tetrapyrrole biosynthesis pathway
-
-
-
METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
Cd2+
Co2+
Cu2+
-
inhibits enzymatic activity. High molecular weight fraction as well as metallothionein are involved in the detoxification of harmful heavy metals
Fe2+
K+
Mg2+
Mn2+
Ni(2+)
Ni2+
Zinc
Zn2+
additional information
Cd2+
-
inhibition at low concentration of substrate and stimulation at high levels of substrate
Cd2+
-
inhibits enzymatic activity. High molecular weight fraction as well as metallothionein are involved in the detoxification of harmful heavy metals
Fe2+
-
partially restores enzyme after inactivation of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolinedisulfonate
K+
-
stimulates, between pH 6.5 and 7.0, K+ is as stimulatory as Mg2+ and the stimulation is almost 2fold
Mg2+
-
enzyme utilizes a catalytic MgA present at a stoichiometry of 4/octamer, an allosteric MgC present at a stoichiometry of 8/octamer and a monovalent metal ion, K+
Mg2+
-
can not activate the apoenzyme alone, but is able to substitute for the second molar equivalent of bound Zn2+ leading to a further 4fold stimulation
Mg2+
-
4 Zn at metal binding site A , 4 Zn at metal binding site B and 8 Mg at metal binding site C are required for full activity per homooctamer
Mg2+
-
chimeric proteins are constructed that contain the aspartate-rich sequences of the pea enzyme or the enzyme from Pseudomonas aeruginosa in place of the naturally occuring cysteine-rich sequence of the human enzyme. The chimeric enzymes are substantially activated by both magnesium and potassium, but not by zinc
Mg2+
-
essentail cofactor, allosteric Mg(II) binds with a Kd of 2.5 mM, 2.3fold activation, binding of 3 Mg(II) per subunit
Mg2+
-
4 Zn at metal binding site A and 8 Mg at metal binding site C are required for full activity per homooctamer
Mg2+
-
stimulates but is not required for activity. Eight Mg2+ ions can be seen in the crystal structure, one per monomer, all bound at the allosteric magnesium-binding site. No metal ion can be seen in the active site
Mg2+
-
binds only 4 Mg2+ per octamer, these 4 Mg2+ allosterically stimulate a metal ion independent catalytic actiovity, in a fashion dependent upon both pH and K+, the allosteric Mg2+ is located in metal binding site C, which is outside the active site. NO evidence is found for metal binding to the potential high-affinity active site metal binding site A and/or B, no direct involvement of Mg2+ in substrate binding and product formation
Mg2+
-
can completrly restore activity after inhibition by EDTA; can completrly restore activity after inhibition by EDTA, stabilizes the oligomeric state but is not essential for octamer formation
Mg2+
-
enzyme responds to Mg2+ but not to Zn2+, enzyme shows two Mg2+ affinities
Zinc
-
contains 1 gatom of zinc per mol of subunit, zinc has a structural rather than a direct catalytic role
Zinc
-
lacks a catalytic ZnA, enzyme can bind Zn(II), presumably as ZnA, at a stoichiometry of 4/octamer with a Kd of 0.2 mM, this high concentration is outside the physiologically significant range
Zinc
-
4 Zn at metal binding site A , 4 Zn at metal binding site B and 8 Mg at metal binding site C are required for full activity per homooctamer
Zinc
-
binds 8 mol of zinc per mol of octamer, zinc may interact with one or more of the highly reactive enzyme thiol groups
Zinc
-
4 Zn at metal binding site A and 4 Zn at metal binding site B are required for full activity per homooctamer
Zinc
-
4 Zn at metal binding site A and 8 Mg at metal binding site C are required for full activity per homooctamer
Zinc
-
8 Zn at metal binding site A and 8 Zn at metal binding site B are required for full activity per homooctamer
Zn2+
-
Zn2+ forms a bond with a sulfhydryl group in the enzyme, the octameric enzyme contains 4 gatom of Zn2+ per mol of enzyme, Zn2+ does not participate in substrate binding nor in the maintenance of the quarternary structure of the enzyme
Zn2+
-
the cysteines of the metal switch sequence of the wild-type enzyme bind a catalytic zinc. Chimeric proteins are constructed that contain the aspartate-rich sequences of the pea enzyme or the enzyme from Pseudomonas aeruginosa in place of the naturally occuring cysteine-rich sequence of the human enzyme. The chimeric enzymes are substantially activated by both magnesium and potassium, but not by zinc.
Zn2+
-
activity is progressively increased with increasing Zn2+ concentrations up to 0.1 mM, inhibition at high concentrations
Zn2+
-
restores enzyme after inactivation by 2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolinedisulfonate
additional information
-
does not require metallic cations for activation
additional information
does not utilize metal ions such as Zn2+ or Mg2+
additional information
-
does not utilize metal ions such as Zn2+ or Mg2+
INHIBITORS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
1,1',1''-[(3-ethoxyprop-1-ene-1,1,2-triyl)triselanyl]tribenzene ethyl 2,3,3-tris(phenylselanyl)prop-2-en-1-yl ether
-
0.6 mM, 65% inhibition
1,1',1''-[(3-ethoxyprop-1-ene-1,1,2-triyl)triselanyl]tris(2,4,6-trimethylbenzene) ethyl 2,3,3-tris[(2,4,6-trimethylphenyl)selanyl]prop-2-en-1-yl ether
-
0.6 mM, 44% inhibition
1,1',1''-[(3-ethoxyprop-1-ene-1,1,2-triyl)triselanyl]tris(4-chlorobenzene) ethyl 2,3,3-tris[(4-chlorophenyl)selanyl]prop-2-en-1-yl ether
-
modest inhibition
2,3-Dimercaptopropanol
-
cysteine and ZnCl2 protects. Dithiothreitol protects inhibition by 1 mM 2,3-dimercaptopropanol in a concentration dependent manner
3-acetyl-4-oxoheptane-1,7-dioic acid
-
formation of a Schiff base complex between the inhibitors and the active site Lys
-
4,7-dioxosebacic acid
-
hanging-drop method, irreversible inhibitor binds by forming Schiff-base linkages with lysines 200 and 253 at the active site. 4,7-dioxosebacic acid is a better inhibitor of the zinc-dependent 5-aminolaevulinic acid dehydratases than of the zinc-independent 5-aminolaevulinic acid dehydratases
4-oxosebaic acid
-
active site-directed irreversible inhibitor, less potent than 4,7-dioxosebaic acid
5-fluorolevulinic acid
-
both inhibitor molecules are covalently bound to two conserved, active-site lysine residues, Lys205 and lys260, through Schiff bases
5-hydroxylaevulinic acid
-
the competitive inhibitor is bound by a Schiff-base link to one of the invariant active-site lysine residues (Lys263). The inhibitor appears to bind in two well defined conformations
7-(3-aminopentan-3-yl)-5-chloroquinolin-8-ol
-
using in silico screening two hexamer-stabilizing inhibitors of PBGS are identified: N-(3-methoxyphenyl)-1-methyl-6-oxo-2-[(pyridin-2-ylmethyl)sulfanyl]-1,6-dihydropyrimidine-5-carboxamide and 7-(3-aminopentan-3-yl)-5-chloroquinolin-8-ol
Al2(SO4)3
-
ALA-D inhibition may be due to the fact that aluminum present in the growth medium can compete with Mg2+ or reduce the expression of ALA-D
alaremycin
-
porphobilinogen synthase is cocrystallized with the alaremycin. At 1.75 A resolution, the crystal structure reveals that the antibiotic efficiently blocks the active site of porphobilinogen synthase. The antibiotic binds as a reduced derivative of 5-acetamido-4-oxo-5-hexenoic acid. The corresponding methyl group is not coordinated by any amino acid residues of the active site, excluding its functional relevance for alaremycin inhibition. Alaremycin is covalently bound by the catalytically important active-site lysine residue 260 and is tightly coordinated by several active-site amino acids
alloxan
-
i.e. 2,4,5,6-tetraoxypyrimidine 5,6-dioxyuracil , 0.00125-0.02 mM alloxan causes a concentration-dependent uncompetitive inhibition. Dithiothreitol (0.7and 1 mM) completely prevents the inhibition induced by 0.01 and 0.02 mM alloxan. Similar protection is obtained in the presence of 2 mMglutathione
arsenic acid
-
inhibition of 5-aminolevulinic acid dehydratase activity by arsenic in excised etiolated maize leaf segments during greening. KNO3, chloramphenical, cycloheximide, DTNB and levulinic aciddecrease inhibition. GSH increase inhibition
Carbonate
-
using a carbonate buffer rather than phosphate causes nearly a 90% drop in activity in the developed assay method
D-fructose
-
formation of a Schiff base with the critical lysine residue of the enzyme is involved in inhibition of the enzyme by hexoses and pentoses
D-ribose
-
formation of a Schiff base with the critical lysine residue of the enzyme is involved in inhibition of the enzyme by hexoses and pentoses
diammine(dichloro)platinum
-
mechanism of inhibition is a direct interaction of the inhibitor with sulfhydryl groups, whereas zinc site appears to be involved with the higher doses only
Ga3+
-
inhibits by competing with Zn2+, IC50: 0.442 mM, GSH has no protective effect, Zn2+ completely recovers inhibition
HgCl2
-
pretreatment with a nontoxic dose of Na2SeO3 partially or totally prevents in vivo mercury effects in kidney, including prevention of inhibition of delta-aminolevulinate dehydratase
In3+
-
inhibits by competing with Zn2+, IC50: 0.298 mM, GSH reduces inhibition, DL-dithiothreitol has modest effect on inhibition, Zn2+ completely recovers inhibition
-
N-(3-methoxyphenyl)-1-methyl-6-oxo-2-[(pyridin-2-ylmethyl)sulfanyl]-1,6-dihydropyrimidine-5-carboxamide
-
using in silico screening two hexamer-stabilizing inhibitors of PBGS are identified: N-(3-methoxyphenyl)-1-methyl-6-oxo-2-[(pyridin-2-ylmethyl)sulfanyl]-1,6-dihydropyrimidine-5-carboxamide and 7-(3-aminopentan-3-yl)-5-chloroquinolin-8-ol
Tl3+
-
inhibits by direct oxidation of essential sulfhydryl groups, IC50: 0.0085 mM, DL-dithiothreitol restores completely enzyme activity inhibited by Tl3+, Zn2+ is unable to change inhibition
2,3-dimercaptopropane-1-sulfonic acid
-
1 mM, 0.5 mM ZnCl2 protects but does not reverse inhibition. Dithiothreitol protects inhibition by 1 mM 2,3-dimercaptopropane-1-sulfonic acid in a concentration dependent manner
2,3-dimercaptopropane-1-sulfonic acid
-
in presence of Hg2+ or Cd2+ the inhibitory potency increases, no change in inhibitory potency by inclusion of Pb2+, Zn2+ does not modify the inhibitory effect
2,3-dimercaptopropane-1-sulfonic acid
-
0.1 mM, 20% inhibition, more pronounced inhibition in combination with Cd2+
5-chlorolevulinic acid
-
inactivation results fromthe initial formation of a Schiff base with lysine-247, followed by alkylation of lysine-195 by the resulting reactive chloroimide
bathocuproine disulfonic acid
-
i.e. 2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolinedisulfonate
Cd2+
-
inhibition at low concentration of substrate and stimulation at high levels of substrate
Cd2+
-
0.1 mM Cd2+ totally inhibits enzyme activity. Dithiothreitol (0.003 mM) is able to restore the inhibition of enzyme activity caused by Cd2+ (0.02 mM)
Cd2+
-
inhibits delta-ALA-D activity. Chelating and antioxidant agents potentiated the inhibition
Cd2+
-
enzyme inhibition in excised etiolated leaf segments during greening. Cd2+ inhibits ALAD activity by affecting the ALA binding to the enzyme and/or disrupting thiol interaction. Inhibition of ALAD activity by Cd2+ is decreased in the presence of nitrogenous compounds, glutamine and NH4NO3, overview. Supply of some essential metal ions, such as Mg2+, Zn2+, and Mn2+, also reduces the inhibition of enzyme activity by Cd2+
D-glucose
-
formation of a Schiff base with the critical lysine residue of the enzyme is involved in inhibition of the enzyme by hexoses and pentoses
D-glucose
-
incubations of erythrocytes for 24 h with glucose results in an increase of delta-ALA-D activity. Incubations of erythrocytes with 100 to 200 mM glucose for 48 h inhibit delta-ALA-D activity
dibutyl diselenide
-
IC50: 0.693 mM, enzyme from liver; IC50: 0.985 mM, enzyme from gill
diphenyl diselenide
-
IC50: 0.076 mM, enzyme from liver; IC50: 0.274 mM, enzyme from gill
EDTA
-
activity can be completely restored by addition of Mg2+ or Mn2+. Co2+, Zn2+, and Ni2+ partially restore EDTA-inhibited activity
Hg2+
-
inhibitory effect is increased by meso-2,3-dimercaptosuccinic acid, inhibition is prevented by dithiothreitol
Hg2+
-
inhibits enzyme in vivo at 6 h and 12 h after treatment. Se4+ abolishes the inhibitory effect of Hg2+
Hg2+
-
the inhibition caused by 0.37 mM Hg2+ is alleviated by addition of 10 mM KNO3. 10 mM NH4Cl and 5 mM sucrose increase the inhibitory effect of Hg2+ on enzyme activity, while 10 mM levulinic acid and 0.0001 mM 5,5'-dithio(bis-2-nitrobenzoic acid) glutamine and glutathione decrease it
meso-2,3-dimercaptosuccinic acid
-
4 mM, 1 mM ZnCl2 protects but does not reverse inhibition. Dithiothreitol protects inhibition by 1 mM meso-2,3-dimercaptosuccinic acid in a concentration dependent manner
meso-2,3-dimercaptosuccinic acid
-
in presence of Hg2+ or Cd2+ the inhibitory potency increases, Zn2+ does not modify the inhibitory effect
Pb2+
-
does not produce a change in the quarternary structure detectable by small angle X-ray scattering
phenyl selenoacetylene
-
inhibition involves conversion of phenyl selenoacetylene to diphenyl diselenide, that induces oxidation of essential -SH groups of the enzyme. Inhibition is partially prevented by incubation under argon atmosphere and is completely prevented by dithiothreitol
phenyl selenoxideacetylene
-
IC50: 0.1 mM, inhibition is antagonized by dithiothreitol
phenyl selenoxideacetylene
-
IC50: 0.045 mM, inhibition is antagonized by dithiothreitol
pyridoxal 5'-phosphate
-
30% inhibition at 1 mM, negligible inhibition at 0.05 mM
sodium selenide
-
IC50: 0.386 mM, enzyme from gill; IC50: 0.902 mM, enzyme from liver
Zn2+
-
the inhibitory zinc is located at a subunit interface using Cys219 and His10 as ligands
Zn2+
-
exocenous addition of zinc results in a decrease by up to 35% in enzyme activity
Zn2+
-
at pH 8.5, 50% inhibition by 0.075 mM. At pH 7.5, 50% inhibition by less than 0.02 mM
Zn2+
-
activity is progressively increased with increasing Zn2+ concentrations up to 0.1 mM, inhibition at high concentrations
additional information
-
the enzyme from human erythrocytes is a potential target for organochalcogens
-
additional information
-
in vivo iron reduction in rat blood has a negative correlation with the activity of delta-ALA-D, overview
-
additional information
-
insensitive to inhibition by hemin and protoporphyrin
-
additional information
no inhibition by 10 mM EDTA or 1,20-phenanthroline
-
additional information
-
no inhibition by 10 mM EDTA or 1,20-phenanthroline
-
ACTIVATING COMPOUND
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
glucose
-
incubations of erythrocytes for 24 h with glucose result in an increase of delta-ALA-D activity. Incubations of erythrocytes with 100 to 200 mM glucose for 48 h inhibit delta-ALA-D activity
KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
additional information
additional information
-
the kinetic data do not follow a simple Michaelis-Menten relationship, but can be attributed to catalysis by two different forms of the enzyme that have different Km-values
-
2.1
5-aminolevulinic acid
-
expressed from expression vector pET28a+, His-tag removed
TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
kcat/KM VALUE [1/mMs-1]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
Ki VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
IC50 VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.442
Ga3+
Bos taurus
-
inhibits by competing with Zn2+, IC50: 0.442 mM, GSH has no protective effect, Zn2+ completely recovers inhibition
0.298
In3+
Bos taurus
-
inhibits by competing with Zn2+, IC50: 0.298 mM, GSH reduces inhibition, DL-dithiothreitol has modest effect on inhibition, Zn2+ completely recovers inhibition
-
0.058
N-(3-methoxyphenyl)-1-methyl-6-oxo-2-[(pyridin-2-ylmethyl)sulfanyl]-1,6-dihydropyrimidine-5-carboxamide
Homo sapiens
-
-
0.0085
Tl3+
Bos taurus
-
inhibits by direct oxidation of essential sulfhydryl groups, IC50: 0.0085 mM, DL-dithiothreitol restores completely enzyme activity inhibited by Tl3+, Zn2+ is unable to change inhibition
0.045
phenyl selenoxideacetylene
Rattus norvegicus
-
IC50: 0.045 mM, inhibition is antagonized by dithiothreitol
0.1
phenyl selenoxideacetylene
Cucumis sativus
-
IC50: 0.1 mM, inhibition is antagonized by dithiothreitol
SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
0.4
additional information
pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
5.9 - 8
-
pH 5.9: about 50% of maximal activity, pH 8.0: about 70% of maximal activity, wild-type enzyme
6.8
8 - 8.6
-
in citrate buffer, Tris-maleate buffer, imidazole buffer and Tris buffer
8.5
additional information
pH RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
6 - 9
-
pH 6.0: about 70% of maximal activity, pH 9.0: about 55% of maximal activity
6.5 - 9.5
-
pH 6.5: about 80% of maximal activity, pH 9.5: about 45% of maximal activity
7 - 10
-
pH 7.0: about 50% of maximal activity, pH 10.0: about 55% of maximal activity
7.5 - 9.8
-
pH 7.5: about 35% of maximal activity, pH 9.8: about 50% of maximal activity
7.6 - 8
-
enzyme activity is not inhibited when the pH is between 7.6 and 8.0, and enzyme activity is only inhibited by 1.3% at pH 8.2
TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
37
45
65
TEMPERATURE RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
25 - 45
-
25°C: about 75% of maximal activity, 45°C: about 85% of maximal activity
37 - 75
-
37°C: about 30% of maximal activity, 75°C: about 90% of maximal activity
pI VALUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
SOURCE
-
delta-ALA-D activity in patients with chronic renal failure with hemodialysis treatment and in patients not undergoing hemodialysis is lower when compared to the control group. delta-ALA-D activity correlates positively with hemoglobin content
-
delta-ALA-D activity is decreased in situations associated to hyperglycemia maintained for long periods. Hypofunction of the thyroid gland, when non-compensated, increase the activity of delta-ALA-D
-
plasma ALA level of the fatigued rats is slightly higher (approximately 1.4fold) than that of the control or food-restricted animals
-
plasma ALA level of the fatigued rats is slightly higher (approximately 1.4fold) than that of the control or food-restricted animals
-
-
delta-aminolevulinate dehydratase activity is lower in hemodialysis patients compared to control
-
-
-
-
210684, 210686, 210687, 210690, 210696, 210701, 210702, 210703, 210706, 210708, 210709, 653399, 666966
-
-
210687, 210708, 210716, 653422, 664767, 664768, 666974, 677945, 691169, 691672, 695196, 714924, 729333
-
in the urine of the fatigued rats, the ALA level increases (approximately 2fold) as compared with that of the control rats
-
in the urine of the fatigued rats, the ALA level increases (approximately 2fold) as compared with that of the control rats
-
LOCALIZATION
ORGANISM
UNIPROT
COMMENTARY
GeneOntology No.
LITERATURE
SOURCE
PDB
SCOP
CATH
ORGANISM
UNIPROT
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pseudomonas aeruginosa (strain ATCC 15692 / PAO1 / 1C / PRS 101 / LMG 12228)
Pyrobaculum calidifontis (strain JCM 11548 / VA1)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
244000
260000
280000
282000
320000
-
gel filtration, recombinant TgPBGS is purified as a stable octamer
additional information
additional information
-
the enzyme is incorporated into mitochondria at a size of 170000 Da and then is gradually converted to a size of 110000 Da, within the mitochondria, hemin stimulates the aggregation of the enzyme in cytosol to a size of 700000 Da
SUBUNITS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
dimer
hexamer
octamer
additional information
?
-
x * 37000, maximally active octamer can dissociate into less active smaller subunits, minimal functional unit is a tetramer, SDS-PAGE
dimer
-
recombinant TgPBGS also shows low levels of dimers, 2 * 40000 Da, SDS-PAGE
hexamer
-
wild type, pH 8.8, catalytic turnover favors octamer, analyzed by gel filtration and anion exchange chromatography
hexamer
-
hexameric structure of the enzyme only shows low activity. Using in silico screening two hexamer-stabilizing inhibitors of PBGS are identified: N-(3-methoxyphenyl)-1-methyl-6-oxo-2-[(pyridin-2-ylmethyl)sulfanyl]-1,6-dihydropyrimidine-5-carboxamide and 7-(3-aminopentan-3-yl)-5-chloroquinolin-8-ol
octamer
-
8 * 34900, equilibrium sedimentation in presence of 6 M guanidine-HCl; 8 * 35000, SDS-PAGE
octamer
-
the enzyme is an obligate oligomer that can exist in functionally distinct quaternary states of different stoichiometries, which are called morpheeins, human PBGS assembles into long-lived morpheeins and is capable of forming either a high activity octamer or a low activity hexamer
octamer
-
wild type, pH 6.9 and pH 8.8, analyzed by gel filtration and anion exchange chromatography
octamer
-
recombinant TgPBGS is purified as a stable octamer, 8 * 40000 Da, SDS-PAGE
additional information
-
dissociation and reassociation of the subunits of immobilized PGB synthase
additional information
-
wild-type enzyme and variant F12L exist in different oligomeric states. The wild-type enzyme exists as an octamer and the F12L variant exists as a hexamer. It appears that any equilibrium between octamer and hexamer most probably proceeds through the interconversion of hugging dimer and the detached dimer
Crystallization/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
crystal structure of enzyme complexed with 4-oxosebaic acid and of enzyme complexed with 4,7-dioxosebaic acid
-
X-ray structure of the enzyme complexed with the inhibitor levulinic acid at 2.0 A resolution
-
hanging drop method, enzyme complexed with the inhibitor laevulinic acid at 2.6 A resolution, unit cell parameters: a = 125.24 A, b = 125.24 A, c = 164.6 A and spec group P42(1)2
-
hanging drop vapor-diffusion method. Crystal structures of the active site of Pseudomonas aeruginosa PBGS with the various inhibitors 5-hydroxylevulinic acid, 5,5'-oxybis(4-oxopentanoic acid), 5,5'-iminobis(4-oxopentanoic acid), 5,5'-thiobis(4-oxopentanoic acid), 5,5'-sulfinylbis(4-oxopentanoic acid) or 5,5'-sulfonylbis(4-oxopentanoic acid)
-
hanging drop vapour diffusion method, crystals of the enzyme complex with levulinic acid solved at 1.67 A resolution, crystals belong to space group P42(1)2 with cell dimensions of a = b = 129.8 A, c = 86.7 A
-
structure of the active-site variant D139N of the Mg2+-dependent enzyme in complex with the inhibitor 5-fluorolevulinic acid
-
hanging-drop vapour diffusion method, X-ray structure of the enzyme in which the catalytic site of the enzyme is complexed with a putative cyclic intermediate composed of both substrate moieties, solved at 0.16 nm resolution
-
the X-ray structure of the enzyme complexed with the competitive inhibitor 5-hydroxylaevulinic acid, determined at a 1.9 A resolution
-
pH STABILITY
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
9
Acutodesmus obliquus
-
highest stability at
210720
TEMPERATURE STABILITY
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
50
GENERAL STABILITY
ORGANISM
UNIPROT
LITERATURE
immobilized enzyme, continous operation for 9 days at 31 C, at a flow rate of 30 ml/h little loss of activity
-
OXIDATION STABILITY
ORGANISM
UNIPROT
LITERATURE
sensitive to oxygen, t1/2: 135 min, the oxygen-inactivated enzyme is restored to full activity by incubation with thiols
-
210688
STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
-20°C, protein concentration above 2 mg/ml, 20 mM phosphate, 5 mM dithiothreitol, pH 6.8, stable for 6 months
-
Purification/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
native enzyme by ammonium sulfate fractionation, anion exchange chromatography, and gel filtration
-
Cloned/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
expression in Escherichia coli
recombinant TgPBGS is expressed in Escherichia coli as a His-tagged fusion protein
-
structure of 5-aminolaevulinic acid dehydratase complexed with the irreversible inhibitor 4,7-dioxosebacic acid
-
very poor expression of full-length cDNA, overexpression of cDNA-2 (56 to 451 aa) as a protein with a histidine tag or as a GST fusion protein in Escherichia coli
-
EXPRESSION
ORGANISM
UNIPROT
LITERATURE
liver and kidney enzyme activity presents a significant decrease in the diabetic/saline group when compared to the control/saline group
-
ENGINEERING
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
H10F
-
mutant enzyme is active but is not inhibited by zinc. H10F binds a catalytic zinc at 0.5/subunit and binds a second nonessential and noninhibitory zinc at 0.5/subunit
K195C
-
mutant enzyme with only 0.1% of the wild-type activity, 2-bromethylamine results in recovery of 10% of the wild-type activity
K247C
-
inactive mutant enzyme, 2-bromethylamine results in recovery of 6% of the wild-type activity
A274K
-
naturally occurring ALAD porphyria-associated human PBGS mutants are shown to have an increased susceptibility to inhibition by both N-(3-methoxyphenyl)-1-methyl-6-oxo-2-[(pyridin-2-ylmethyl)sulfanyl]-1,6-dihydropyrimidine-5-carboxamide and 7-(3-aminopentan-3-yl)-5-chloroquinolin-8-ol
E89K
F12L
R240A
-
mutant enzyme assembles into a metastable hexamer, which can undergo a reversible conversion to the octamer in the presence of substrate
V153M