Any feedback?
Information on EC 2.1.1.248 - methylamine-corrinoid protein Co-methyltransferase and Organism(s) Methanosarcina barkeri and UniProt Accession Q9P9L4
for references in articles please use BRENDA:EC2.1.1.248Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
EC Tree
2.1.1.248 methylamine-corrinoid protein Co-methyltransferaseIUBMB Comments
The enzyme, which catalyses the transfer of a methyl group from methylamine to a methylamine-specific corrinoid protein (MtmC), is involved in methanogenesis from methylamine. The enzyme contains the unusual amino acid pyrrolysine . Methylation of the corrinoid protein requires the central cobalt to be in the Co(I) state. During methylation the cobalt is oxidized to the Co(III) state. The methylated corrinoid protein is substrate for EC 2.1.1.247, methylated methylamine-specific corrinoid protein:coenzyme M methyltransferase.
Specify your search results
Word Map
- 2.1.1.248
- methanosarcina
- barkeri
- methyltransferases
- pyrrolysine
-
amber
-
methanogenesis
-
methanogen
-
in-frame
- trnapyl
- dimethylamine
- acetivorans
-
pyrrolysyl-trna
-
aminoacylated
- lysyl-trna
-
dimethylarsinic
- synthetases
- arsenite
- monomethylarsonate
- lysrs1
- selenocysteine
-
pylts
-
synthetase-like
-
methylarsonic
The taxonomic range for the selected organisms is: Methanosarcina barkeri
The expected taxonomic range for this enzyme is: Archaea, Bacteria
The expected taxonomic range for this enzyme is: Archaea, Bacteria
Reaction Schemes
+
=
+
+
a [Co(I) methylamine-specific corrinoid protein]
=
a [methyl-Co(III) methylamine-specific corrinoid protein]
+
Synonyms
monomethylamine methyltransferase, mtmb1, mmamt, mma methyltransferase, monomethylamine:mmcp methyltransferase, mma:mmcp methyltransferase, 
more
topSYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
MMAMT
MtmB
SYSTEMATIC NAME
IUBMB Comments
monomethylamine:5-hydroxybenzimidazolylcobamide Co-methyltransferase
The enzyme, which catalyses the transfer of a methyl group from methylamine to a methylamine-specific corrinoid protein (MtmC), is involved in methanogenesis from methylamine. The enzyme contains the unusual amino acid pyrrolysine [3]. Methylation of the corrinoid protein requires the central cobalt to be in the Co(I) state. During methylation the cobalt is oxidized to the Co(III) state. The methylated corrinoid protein is substrate for EC 2.1.1.247, methylated methylamine-specific corrinoid protein:coenzyme M methyltransferase.
CAS REGISTRY NUMBER
COMMENTARY
53414-88-3
methylcobalamin-coenzyme M methyltransferase, EC 2.1.1.246 to EC 2.1.1.253
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
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
-
-
-
?
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
additional information
?
-
model for MtmB methylation of Co(I) corrinoid cofactor with monomethylamine. Y335 and Q333 are proposed to assist in the initial MtmB binding of monomethylamine and positioning such that electrophilic attack of the C-2 atom on the lone electron pair of the nitrogen of unionized monomethylamine occurs. The residues can also serve to H-bond with the ammonia released from the pyrroline ring, enhancing the equilibrium between 2-aminopyrrolysine and pyrrolysine in the direction of product removal from the enzyme, model of pyrrolysine function
-
-
?
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
-
-
-
-
?
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
-
-
-
?
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
-
-
-
?
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
-
catalytic cycle of MMA:CoM methyl transfer, overview
-
-
?
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
the methylamine-specific corrinoid protein MtmC cycles between methyl-Co(III)- and Co(I)-MtmC during catalysis. Methanogen methylotrophic corrinoid proteins such as MtmC are methylated in the Co(I) state, forming a hexacoordinate methyl-Co(III) species whose demethylation regenerates Co (I) corrinoid. Pyrrolysine in MtmB mediates methylation of MtmC
-
-
?
NATURAL SUBSTRATE
NATURAL 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
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
-
-
-
?
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
-
-
-
-
?
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
-
-
-
?
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
-
-
-
?
methylamine + a [Co(I) methylamine-specific corrinoid protein]
a [methyl-Co(III) methylamine-specific corrinoid protein] + ammonia
-
catalytic cycle of MMA:CoM methyl transfer, overview
-
-
?
ACTIVATING COMPOUND
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
RamA
-
a 60-kDa monomeric iron sulfur protein, is a protein required for reductive activation of corrinoid-dependent methylamine methyltransferase reactions in methanogenic archaea, it is required for in vitro ATP-dependent reductive activation of methylamine:CoM methyl transfer mediating the ATP-dependent reductive activation of Co(II) corrinoid to the Co(I) state for the monomethylamine corrinoid protein, MtmC, overview. RamA affects both lag times and rates during assay of MMA:CoM methyl transfer
-
SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
SOURCE
GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
metabolism
physiological function
additional information
metabolism
-
archaeal methane formation from methylamines is initiated by distinct methyltransferases with specificity for monomethylamine, dimethylamine, or trimethylamine. Each methylamine methyltransferase methylates a cognate corrinoid protein, which is subsequently demethylated by a second methyltransferase to form methyl-coenzyme M, the direct methane precursor
metabolism
biochemistry of methane formation by Methanosarcina species from monomethylamine, dimethylamine, and trimethylamine: methanogenesis from these substrates is initiated by three methyltransferases that specifically methylate their cognate corrinoid proteins with one of these methylamines, cf. EC 2.1.1.250 and EC 2.1.1.249, overview
physiological function
the enzyme is involved in the corrinoid-dependent demethylation of methylamines, which are used for coenzyme M methylation, homology modeling of MtmC, the methylamine-specific corrinoid protein. Pyrrolysine in MtmB mediates methylation of MtmC
physiological function
-
the MMAMT polypeptide is rate-limiting for methyl transfer until at a 2fold molar excess over monomethylamine corrinoid protein, MMCP. MMAMT and MMCP form a complex. MMCP is the major corrinoid protein for methanogenesis from monomethylamine
additional information
single in-frame amber UAG codons are found in the genes encoding MtmB, MtbB, or MttB, the methyltransferases initiating methane formation from monomethylamine, dimethylamine, or trimethylamine, respectively, in certain Archaea. The amber codon codes for pyrrolysine, the 22nd genetically encoded amino acid found in nature
additional information
single in-frame amber UAG codons are found in the genes encoding MtmB, MtbB, or MttB, the methyltransferases initiating methane formation from monomethylamine, dimethylamine, or trimethylamine, respectively, in certain Archaea. The amber codon codes for pyrrolysine, the 22nd genetically encoded amino acid found in nature
additional information
single in-frame amber UAG codons are found in the genes encoding MtmB, MtbB, or MttB, the methyltransferases initiating methane formation from monomethylamine, dimethylamine, or trimethylamine, respectively, in certain Archaea. The amber codon codes for pyrrolysine, the 22nd genetically encoded amino acid found in nature
additional information
single in-frame amber UAG codons are found in the genes encoding MtmB, MtbB, or MttB, the methyltransferases initiating methane formation from monomethylamine, dimethylamine, or trimethylamine, respectively, in certain Archaea. The amber codon codes for pyrrolysine, the 22nd genetically encoded amino acid found in nature
additional information
the enzyme contains pyrrolysine at the UAG posotion, crystal structure of MtmB reveals lysine, but with epsilonN in amide linkage with (4R,5R)-4 substituted-pyrroline-5-carboxylate
UNIPROT
ENTRY NAME
ORGANISM
NO. OF AA
NO. OF TRANSM. HELICES
MOLECULAR WEIGHT[Da]
SOURCE
SEQUENCE
LOCALIZATION PREDICTION
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable).
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable). MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
50000
SUBUNIT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
homotrimer
additional information
additional information
mass spectrometric structure analysis, overview, primary structure of MtmB
additional information
mass spectrometric structure analysis, overview, primary structure of MtmB
additional information
tertiary structures of MtmB and its substrate, MtmC
CRYSTALLIZATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
two crystal forms of MtmB obtained from solutions containing NaCl or (NH4)2SO4. In the NaCl crystal form, the pyrroline is unmodified at the C-2 position. The second crystal form is a mixture of two pyrrolysine states. Crystal structure analysis, overview
PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
native enzyme, separation from co-purifiying MtmC, the methylamine-specific corrinoid protein, by gel filtration
native MtmB from monomethylamine-grown cells, by two different steps of anionexchange chromatography, followed by gel filtration and another step of anion exchange chromatography to near homogeneity
-
native MtmB from monomethylamine-grown cells, by two different steps of anionexchange chromatography, followed by gel filtration and another step of anion exchange chromatography to near homogeneity, co-purification with the monomethylamine-specific corrinoid protein MtmC
-
CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
gene mtmB, DNA and amino acid sequence determination and analysis, genetic organization, the open reading frame of mtmB is interrupted by a single in-frame, midframe, UAG codon. A mechanism that circumvents UAG-directed termination of translation must operate during expression of mtmB in this methanogen. Analysis of the clustered genes encoding the methyltransferases of methanogenesis from monomethylamine and determination of transcript start sites. Cloning and expression of MtmB in Escherichia coli strain DH5alpha
gene mtmB1, DNA and amino acid sequence determination and analysis, UAG is not the stop codon in the encoding gene, no UAG modification. The mtmB1 amber codon encodes pyrrolysine in UAG, crystal structure of MtmB reveals lysine, but with epsilonN in amide linkage with (4R,5R)-4 substituted-pyrroline-5-carboxylate
REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Krzycki, J.
Function of genetically encoded pyrrolysine in corrinoid-dependent methylamine methyltransferases
Curr. Opin. Chem. Biol.
8
484-491
2004
Methanosarcina barkeri (O30642)
Burke, S.; Lo, S.; Krzycki, J.
Clustered genes encoding the methyltransferases of methanogenesis from monomethylamine
J. Bacteriol.
180
3432-3440
1998
Methanosarcina barkeri (O30642), Methanosarcina barkeri MS / DSM 800 (O30642)
Burke, S.; Krzycki, J.
Reconstitution of monomethylamine:coenzyme M methyl transfer with a corrinoid protein and two methyltransferases purified from Methanosarcina barkeri
J. Biol. Chem.
272
16570-16577
1997
Methanosarcina barkeri
Soares, J.; Zhang, L.; Pitsch, R.; Kleinholz, N.; Jones, R.; Wolff, J.; Amster, J.; Green-Church, K.; Krzyck, J.
The residue mass of L-pyrrolysine in three distinct methylamine methyltransferases
J. Biol. Chem.
280
36962-36969
2005
Methanosarcina barkeri (O30642), Methanosarcina barkeri (Q9P9L4), Methanosarcina barkeri MS / DSM 800 (O30642), Methanosarcina barkeri MS / DSM 800 (Q9P9L4)
EXTERNAL LINKS (specific for EC-Number 2.1.1.248)
Use of this online version of BRENDA is free under the CC BY 4.0 license. See terms of use for full details.
Release 2023.1 (January 2023)
Legal
Curated at
Member of
