A0A7X6D203 · A0A7X6D203_9ACTN

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.

Caution

The sequence shown here is derived from an EMBL/GenBank/DDBJ whole genome shotgun (WGS) entry which is preliminary data.

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 site237Zn2+ (UniProtKB | ChEBI)
Binding site303Zn2+ (UniProtKB | ChEBI)
Binding site304Zn2+ (UniProtKB | ChEBI)
Binding site744-748methylcob(III)alamin (UniProtKB | ChEBI)
Binding site747Co (UniProtKB | ChEBI) of methylcob(III)alamin (UniProtKB | ChEBI); axial binding residue
Binding site792methylcob(III)alamin (UniProtKB | ChEBI)
Binding site850methylcob(III)alamin (UniProtKB | ChEBI)
Binding site933S-adenosyl-L-methionine (UniProtKB | ChEBI)
Binding site1114S-adenosyl-L-methionine (UniProtKB | ChEBI)
Binding site1168-1169S-adenosyl-L-methionine (UniProtKB | ChEBI)

GO annotations

AspectTerm
Cellular Componentcytosol
Molecular Functioncobalamin binding
Molecular Functionmethionine synthase activity
Molecular Functionzinc ion binding
Biological Processhomocysteine metabolic process
Biological Processmethylation
Biological Processtetrahydrofolate 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
    • ORF names
      HCN56_14445

Organism names

  • Taxonomic identifier
  • Organism
  • Strain
    • NCL716
  • Taxonomic lineage
    Bacteria > Actinomycetota > Actinomycetes > Kitasatosporales > Streptomycetaceae > Streptomyces

Accessions

  • Primary accession
    A0A7X6D203

Proteomes

Subcellular Location

Family & Domains

Features

Showing features for domain, region.

Type
IDPosition(s)Description
Domain15-318Hcy-binding
Domain349-612Pterin-binding
Domain641-734B12-binding N-terminal
Domain734-871B12-binding
Region876-908Disordered
Domain886-1172AdoMet 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
    1,172
  • Mass (Da)
    126,943
  • Last updated
    2021-06-02 v1
  • Checksum
    E57AD97167CCEACD
MASSTLPTASPAQRIAAFREAIASRVVVADGGMGTMLQAADPTLEDFENLEGCNEILNVTRPDIVRSVHAEYFAAGVDCVETNTFGANHAALGEYDIPERVHELSEAGARVAREAADLFAAEDGRMRWVLGSMGPGTKLPTLGHAPYGLLRDAYERNADGLLAGGADALLVETTQDLLQTKAAVIGARRALTAAGSEAPLIVSVTVETTGTMLLGSEIGAALTALEPLGIDMIGMNCATGPAEMSEHLRYLAQHARVPLACMPNAGLPVLGRDGAHYPLTAPELADAQETFVNDFGLSLIGGCCGTTPEHMRQVVERVRGLTPAEREPRPEPGAASLYQTVPFQQDASYLAIGERTNANGSRKFREAMLEARWDDCVELAREQIREGAHFLDLCVDYVGRDGTADMAELAGRLATASTLPIVLDSTEVEVIRTGLEHLGGRAVINSVNYEDGDGPESRFARITELAAEHGAALIALTIDEEGQARTAEKKVEIAERLIADLTGNWGIEESDILIDCLTFTICTGQEESRGDGVATIEAIRELKRRHPRVQTTLGLSNISFGLNPAARMVLNSVFLDECVKAGLDSAIVHAAKIVPIARLAEEEAAVALDLIHDRRREGYDPLQRLLELFDGVDAKSVRAGRAEELAALPLEERLRRRIIEGERNGLEADLEEALTERPALAIVNETLLAGMKTVGELFGSGQMQLPFVLQSAEVMKTAVAHLEPHMEKSDEDGKGTIVLATVRGDVHDIGKNLVDIILSNNGYNVVNLGIKQPVNAILEAAAEHRADVIGMSGLLVKSTVIMKENLEELNARGMAADYPVILGGAALTRAYVEQDLHEIYDGEVRYARDAFEGLRLMDALIGVKRGVPGVTLPELKQRRVPARTAPRPTAPEEAEAPPSRSATATDVPVPAAPFTGTRIVKGIALKEYASWLDEDALFKGQWGLKGSRSGDGPDYQELLESEGRPRLRGWLDRLHTDNLLEAAVVHGYFPCHADGDDLVILDEDGRERTRFTFPRQSRGRHLCLADFFRPKESGELDVVGLQVVTVGSRIGEATGELFAADAYRDYLELHGLSVQLAEALAEYWHARVRQELGIGGSDPAELSGMFRTEYQGCRYSLGYPACPNLEDRAKIAELLQPERIGVKLSEEFQLHPEQSTDAIVLHHPEANYFNAR

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
JAAVJD010000105
EMBL· GenBank· DDBJ
NJQ06753.1
EMBL· GenBank· DDBJ
Genomic DNA

Similar Proteins

Disclaimer

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