Q6R7M2 · Q6R7M2_RHIFR

Function

function

Catalyzes the transfer of a methyl group from methyl-cobalamin to homocysteine, yielding enzyme-bound cob(I)alamin and methionine. Subsequently, remethylates the cofactor using methyltetrahydrofolate.

Catalytic activity

Cofactor

Protein has several cofactor binding sites:
Zn2+ (UniProtKB | Rhea| CHEBI:29105 )

methylcob(III)alamin (UniProtKB | Rhea| CHEBI:28115 )

Pathway

Amino-acid biosynthesis; L-methionine biosynthesis via de novo pathway; L-methionine from L-homocysteine (MetH route): step 1/1.

Features

Showing features for binding site.

TypeIDPosition(s)Description
Binding site262Zn2+ (UniProtKB | ChEBI)
Binding site325Zn2+ (UniProtKB | ChEBI)
Binding site326Zn2+ (UniProtKB | ChEBI)
Binding site708methylcob(III)alamin (UniProtKB | ChEBI)
Binding site775-779methylcob(III)alamin (UniProtKB | ChEBI)
Binding site778Co (UniProtKB | ChEBI) of methylcob(III)alamin (UniProtKB | ChEBI); axial binding residue
Binding site823methylcob(III)alamin (UniProtKB | ChEBI)
Binding site827methylcob(III)alamin (UniProtKB | ChEBI)
Binding site880methylcob(III)alamin (UniProtKB | ChEBI)
Binding site967S-adenosyl-L-methionine (UniProtKB | ChEBI)
Binding site1156S-adenosyl-L-methionine (UniProtKB | ChEBI)
Binding site1211-1212S-adenosyl-L-methionine (UniProtKB | ChEBI)

GO annotations

AspectTerm
Molecular Functioncobalamin binding
Molecular Functionmethionine synthase activity
Molecular Functionzinc ion binding
Biological Processmethylation
Biological Processpteridine-containing compound metabolic process

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Methionine synthase
  • EC number
  • Alternative names
    • 5-methyltetrahydrofolate--homocysteine methyltransferase

Gene names

    • Name
      metH

Organism names

  • Taxonomic identifier
  • Strain
    • RT19
  • Taxonomic lineage
    Bacteria > Pseudomonadota > Alphaproteobacteria > Hyphomicrobiales > Rhizobiaceae > Sinorhizobium/Ensifer group > Sinorhizobium

Accessions

  • Primary accession
    Q6R7M2

Family & Domains

Features

Showing features for domain.

TypeIDPosition(s)Description
Domain21-340Hcy-binding
Domain371-632Pterin-binding
Domain664-758B12-binding N-terminal
Domain765-901B12-binding
Domain917-1249AdoMet activation

Domain

Modular enzyme with four functionally distinct domains. The isolated Hcy-binding domain catalyzes methyl transfer from free methylcobalamin to homocysteine. The Hcy-binding domain in association with the pterin-binding domain catalyzes the methylation of cob(I)alamin by methyltetrahydrofolate and the methylation of homocysteine. The B12-binding domain binds the cofactor. The AdoMet activation domain binds S-adenosyl-L-methionine. Under aerobic conditions cob(I)alamin can be converted to inactive cob(II)alamin. Reductive methylation by S-adenosyl-L-methionine and flavodoxin regenerates methylcobalamin.

Sequence similarities

Belongs to the vitamin-B12 dependent methionine synthase family.

Keywords

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    1,256
  • Mass (Da)
    137,930
  • Last updated
    2004-07-05 v1
  • Checksum
    6BBD464C980A3B70
MPAAAFLFGDVSPKPDGSEIFRVLRQATAGRILIMDGAMGTEIQQLGLAEDHFRGDRFGGCSCHQQGNNDLLTLTQPKAIEDIHYRYAIAGADILETNTFSSTRIAQADYGMEDMVYELNRDGARLARRAAKRAEAEDGRRRFVAGALGPTNRTASISPDVNNPGYRAVTFDDLRLAYAEQVHGLIDGGADIILIETVFDTLNAKAAIFATQEIFAEKGVRLPIMISGTITDLSGRTLSGQTSEAFWYSVRHAEPFTIGLNCALGANAMRAHIDELSSVADTLICAYPNAGLPNEFGRYDESPEAMAAQIEGFARDGLVNIVGGCCGSTPDHIRAIAEAVEKYPPREIPQIERRMRLSGLEPFTFTDEIPFVNVGERTNVTGSAKFRKLITAGDYAAALDVARDQVANGAQIIDVNMDEGLIDSKQVMVEFLNLVASEPDIARVPVMIDSSKWEVIEAGLQCVQGKALVNSISLKEGEEAFLDHARLVRAYGAAVVVMAFDEKGQADTKARKVEICTRAYRLLTENVGFPPEDIIFDPNIFAVATGIEEHNNYGVDFIEAAHEIIASLPHVHVSGGVSNLSFSFRGNEPVREAMHAVFLYHAIQAGMDMGIVNAGQLAVYDAIDPDLREACEDVVLNRRADATERLLEVAKGYRGQGGAQGREKDLAWRQWSVEKRLEHALVNGITEFIEADTEEARRAAERPLHVIEGPLMAGMNVVGDLFGAGKMFLPQVVKSARVMKQAVAVLLPYMEVEKAANGGDARESAGKILMATVKGDVHDIGKNIVGVVLACNNYEIIDLGVMVPSARILEVAREQKVDAIGLSGLITPSLDEMVHVASELEREGFDIPLLIGGATTSRVHTAVKINPRYTLGQTVYVTDASRAVGVVSSLMSPEAREAYQETVRAEYLKVAEAHARNEAEKRRLPLSKARANAHRLDWDAYRPKTPSFLGTRVFESWDLAELARYIDWTPFFQAWELKGVYPRILADEKQGAAARQLFDDAQAMVAKIVAEKWFAPKAVVGFWPAGSIGDDIRLFTDENRRSELATLFTLRQQLAKRDGRPNVALSDFVAPAESGRGDYVGGFVVTAGIEEVALAERFERANDDYSSIMVKALADRFAEAFAERMHEYVRKELWAYAPEEAFTPEELIAEPYRGIRPAPGYPAQPDHTEKETLFRLLDAEAAIGVKLTESFAMWPGSSVSGLYIGHPDAYYFGVAKIERDQVEDYAQRKRMGVHEAERWLSPILNYVPMPETQAAE

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
AY509252
EMBL· GenBank· DDBJ
AAR99583.1
EMBL· GenBank· DDBJ
Genomic DNA

Similar Proteins

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