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Methionine synthase domain superfamily

SCOP classification
Root:   SCOP hierarchy in SUPERFAMILY [ 0] (11)
Class:   All alpha proteins [ 46456] (284)
Fold:   Methionine synthase domain-like [ 47643] (3)
Superfamily:   Methionine synthase domain [ 47644]
Families:   Methionine synthase domain [ 47645]

Superfamily statistics
Genomes (1,644) Uniprot 2018_03 genome PDB chains (SCOP 1.75)
Domains 2,176 19,249 3
Proteins 2,176 19,247 3

Functional annotation
General category Metabolism
Detailed category Amino acids metabolism and transport

Function annotation of SCOP domain superfamilies

Enzyme Commission (EC)

(show details)
EC termFDR (all)SDEO levelAnnotation (direct or inherited)
Enzyme Commission (EC)Transferring one-carbon groups0Least InformativeDirect
Enzyme Commission (EC)Methyltransferases0Moderately InformativeDirect
Enzyme Commission (EC)Methionine synthase0Highly InformativeDirect

Document: EC annotation of SCOP domains

Enzyme Commission (EC)

(show details)
EC termFDR (all)SDEC levelAnnotation (direct or inherited)
Enzyme Commission (EC)Transferring one-carbon groups0Moderately InformativeDirect

Document: EC annotation of SCOP domains

UniProtKB KeyWords (KW)

(show details)
KW termFDR (all)SDKW levelAnnotation (direct or inherited)
Biological processAmino-acid biosynthesis0.00000000001206Moderately InformativeDirect
Biological processMethanogenesis0Highly InformativeDirect
Biological processMethionine biosynthesis0Highly InformativeDirect
DomainRepeat0Least InformativeDirect
Molecular functionMetal-binding0Least InformativeDirect
Molecular functionZinc0.0000017Least InformativeDirect
Molecular functionCobalt0InformativeDirect
Molecular functionS-adenosyl-L-methionine0.00000000000004489InformativeDirect
Molecular functionCobalamin0.00000000001528Highly InformativeDirect
Post-translational modificationTransferase0.00005937Least InformativeDirect
Post-translational modificationMethyltransferase0InformativeDirect

Document: KW annotation of SCOP domains

InterPro annotation
Cross references IPR003759 SSF47644 Protein matches

Cobalamin-dependent methionine synthase is a large modular protein that catalyses methyl transfer from methyltetrahydrofolate (CH3-H4folate) to homocysteine. During the catalytic cycle, it supports three distinct methyl transfer reactions, each involving the cobalamin (vitamin B12) cofactor and a substrate bound to its own functional unit [PubMed11731805]. The cobalamin cofactor plays an essential role in this reaction, accepting the methyl group from CH3-H4folate to form methylcob(III)alamin, and in turn donating the methyl group to homocysteine to generate methionine and cob(I)alamin.

Methionine synthase is a large enzyme composed of four structurally and functionally distinct modules: the first two modules bind homocysteine and CH3-H4folate, the third module binds the cobalamin cofactor and the C-terminal module binds S-adenosylmethionine. The cobalamin-binding module is composed of two structurally distinct domains: a 4-helical bundle cap domain (residues 651-740 in the Escherichia coli enzyme) and an alpha/beta B12-binding domain (residues 741-896) . The 4-helical bundle forms a cap over the alpha/beta domain, which acts to shield the methyl ligand of cobalamin from solvent [PubMed8939751]. Furthermore, in the conversion to the active conformation of this enzyme, the 4-helical cap rotates to allow the cobalamin cofactor to bind the activation domain . The alpha/beta domain is a common cobalamin-binding motif, whereas the 4-helical bundle domain with its methyl cap is a distinctive feature of methionine synthases.

This entry represents the 4-helical bundle cap domain. This domain is also present in other shorter proteins that bind to B12, and is always found N-terminus to the alpha/beta B12-binding domain.

InterPro database

PDBeMotif information about ligands, sequence and structure motifs
Cross references PDB entries
Ligand binding statistics
Nucleic-acid binding statistics
Occurrence of secondary structure elements
Occurrence of small 3D structural motifs

PDBeMotif resource

Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Enzyme Commission (EC) · Enzyme Commission (EC) · UniProtKB KeyWords (KW) ]

Internal database links

Browse genome assignments for this superfamily. The SUPERFAMILY hidden Markov model library has been used to carry out SCOP domain assignments to all genomes at the superfamily level.

Alignments of sequences to 1 models in this superfamily are available by clicking on the 'Alignments' icon above. PDB sequences less than 40% identical are shown by default, but any other sequence(s) may be aligned. Select PDB sequences, genome sequences, or paste in or upload your own sequences.

Browse and view proteins in genomes which have different domain combinations including a Methionine synthase domain domain.

Examine the distribution of domain superfamilies, or families, across the major taxonomic kingdoms or genomes within a kingdom. This gives an immediate impression of how superfamilies, or families, are restricted to certain kingdoms of life.

Explore domain occurrence network where nodes represent genomes and edges are domain architectures (shared between genomes) containing the superfamily of interest.

There are 1 hidden Markov models representing the Methionine synthase domain superfamily. Information on how the models are built, and plots showing hydrophobicity, match emmission probabilities and insertion/deletion probabilities can be inspected.

Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Enzyme Commission (EC) · Enzyme Commission (EC) · UniProtKB KeyWords (KW) · Internal database links ]