ID A0A1G9IYV4_9SPHI Unreviewed; 1219 AA.
AC A0A1G9IYV4;
DT 22-NOV-2017, integrated into UniProtKB/TrEMBL.
DT 22-NOV-2017, sequence version 1.
DT 27-MAR-2024, entry version 35.
DE RecName: Full=Methionine synthase {ECO:0000256|ARBA:ARBA00013998, ECO:0000256|PIRNR:PIRNR000381};
DE EC=2.1.1.13 {ECO:0000256|ARBA:ARBA00012032, ECO:0000256|PIRNR:PIRNR000381};
DE AltName: Full=5-methyltetrahydrofolate--homocysteine methyltransferase {ECO:0000256|ARBA:ARBA00031040, ECO:0000256|PIRNR:PIRNR000381};
GN ORFNames=SAMN04487898_11721 {ECO:0000313|EMBL:SDL30271.1};
OS Pedobacter sp. ok626.
OC Bacteria; Bacteroidota; Sphingobacteriia; Sphingobacteriales;
OC Sphingobacteriaceae; Pedobacter.
OX NCBI_TaxID=1761882 {ECO:0000313|EMBL:SDL30271.1, ECO:0000313|Proteomes:UP000198594};
RN [1] {ECO:0000313|EMBL:SDL30271.1}
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=OK626 {ECO:0000313|EMBL:SDL30271.1};
RA de Groot N.N.;
RL Submitted (OCT-2016) to the EMBL/GenBank/DDBJ databases.
CC -!- FUNCTION: Catalyzes the transfer of a methyl group from methyl-
CC cobalamin to homocysteine, yielding enzyme-bound cob(I)alamin and
CC methionine. Subsequently, remethylates the cofactor using
CC methyltetrahydrofolate. {ECO:0000256|ARBA:ARBA00025552,
CC ECO:0000256|PIRNR:PIRNR000381}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=(6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine =
CC (6S)-5,6,7,8-tetrahydrofolate + L-methionine; Xref=Rhea:RHEA:11172,
CC ChEBI:CHEBI:18608, ChEBI:CHEBI:57453, ChEBI:CHEBI:57844,
CC ChEBI:CHEBI:58199; EC=2.1.1.13;
CC Evidence={ECO:0000256|ARBA:ARBA00001700,
CC ECO:0000256|PIRNR:PIRNR000381};
CC -!- COFACTOR:
CC Name=Zn(2+); Xref=ChEBI:CHEBI:29105;
CC Evidence={ECO:0000256|ARBA:ARBA00001947,
CC ECO:0000256|PIRNR:PIRNR000381, ECO:0000256|PROSITE-ProRule:PRU00333};
CC -!- COFACTOR:
CC Name=methylcob(III)alamin; Xref=ChEBI:CHEBI:28115;
CC Evidence={ECO:0000256|ARBA:ARBA00001956,
CC ECO:0000256|PIRNR:PIRNR000381, ECO:0000256|PIRSR:PIRSR000381-1};
CC -!- PATHWAY: Amino-acid biosynthesis; L-methionine biosynthesis via de novo
CC pathway; L-methionine from L-homocysteine (MetH route): step 1/1.
CC {ECO:0000256|ARBA:ARBA00005178, ECO:0000256|PIRNR:PIRNR000381}.
CC -!- DOMAIN: Modular enzyme with four functionally distinct domains. The
CC isolated Hcy-binding domain catalyzes methyl transfer from free
CC methylcobalamin to homocysteine. The Hcy-binding domain in association
CC with the pterin-binding domain catalyzes the methylation of
CC cob(I)alamin by methyltetrahydrofolate and the methylation of
CC homocysteine. The B12-binding domain binds the cofactor. The AdoMet
CC activation domain binds S-adenosyl-L-methionine. Under aerobic
CC conditions cob(I)alamin can be converted to inactive cob(II)alamin.
CC Reductive methylation by S-adenosyl-L-methionine and flavodoxin
CC regenerates methylcobalamin. {ECO:0000256|PIRNR:PIRNR000381}.
CC -!- SIMILARITY: Belongs to the vitamin-B12 dependent methionine synthase
CC family. {ECO:0000256|ARBA:ARBA00010398}.
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DR EMBL; FNEX01000017; SDL30271.1; -; Genomic_DNA.
DR AlphaFoldDB; A0A1G9IYV4; -.
DR STRING; 1761882.SAMN04487898_11721; -.
DR UniPathway; UPA00051; UER00081.
DR Proteomes; UP000198594; Unassembled WGS sequence.
DR GO; GO:0031419; F:cobalamin binding; IEA:UniProtKB-UniRule.
DR GO; GO:0008705; F:methionine synthase activity; IEA:UniProtKB-UniRule.
DR GO; GO:0008270; F:zinc ion binding; IEA:UniProtKB-UniRule.
DR GO; GO:0032259; P:methylation; IEA:UniProtKB-KW.
DR GO; GO:0042558; P:pteridine-containing compound metabolic process; IEA:InterPro.
DR CDD; cd02069; methionine_synthase_B12_BD; 1.
DR CDD; cd00740; MeTr; 1.
DR Gene3D; 3.40.50.280; Cobalamin-binding domain; 1.
DR Gene3D; 1.10.288.10; Cobalamin-dependent Methionine Synthase, domain 2; 1.
DR Gene3D; 3.20.20.20; Dihydropteroate synthase-like; 1.
DR Gene3D; 3.20.20.330; Homocysteine-binding-like domain; 1.
DR Gene3D; 1.10.1240.10; Methionine synthase domain; 1.
DR Gene3D; 3.10.196.10; Vitamin B12-dependent methionine synthase, activation domain; 1.
DR InterPro; IPR003759; Cbl-bd_cap.
DR InterPro; IPR006158; Cobalamin-bd.
DR InterPro; IPR036724; Cobalamin-bd_sf.
DR InterPro; IPR011005; Dihydropteroate_synth-like_sf.
DR InterPro; IPR003726; HCY_dom.
DR InterPro; IPR036589; HCY_dom_sf.
DR InterPro; IPR033706; Met_synthase_B12-bd.
DR InterPro; IPR011822; MetH.
DR InterPro; IPR036594; Meth_synthase_dom.
DR InterPro; IPR000489; Pterin-binding_dom.
DR InterPro; IPR004223; VitB12-dep_Met_synth_activ_dom.
DR InterPro; IPR037010; VitB12-dep_Met_synth_activ_sf.
DR NCBIfam; TIGR02082; metH; 1.
DR PANTHER; PTHR45833; METHIONINE SYNTHASE; 1.
DR PANTHER; PTHR45833:SF1; METHIONINE SYNTHASE; 1.
DR Pfam; PF02310; B12-binding; 1.
DR Pfam; PF02607; B12-binding_2; 1.
DR Pfam; PF02965; Met_synt_B12; 1.
DR Pfam; PF00809; Pterin_bind; 1.
DR Pfam; PF02574; S-methyl_trans; 1.
DR PIRSF; PIRSF000381; MetH; 1.
DR SMART; SM01018; B12-binding_2; 1.
DR SUPFAM; SSF52242; Cobalamin (vitamin B12)-binding domain; 1.
DR SUPFAM; SSF51717; Dihydropteroate synthetase-like; 1.
DR SUPFAM; SSF82282; Homocysteine S-methyltransferase; 1.
DR SUPFAM; SSF56507; Methionine synthase activation domain-like; 1.
DR SUPFAM; SSF47644; Methionine synthase domain; 1.
DR PROSITE; PS50974; ADOMET_ACTIVATION; 1.
DR PROSITE; PS51332; B12_BINDING; 1.
DR PROSITE; PS51337; B12_BINDING_NTER; 1.
DR PROSITE; PS50970; HCY; 1.
DR PROSITE; PS50972; PTERIN_BINDING; 1.
PE 3: Inferred from homology;
KW Amino-acid biosynthesis {ECO:0000256|ARBA:ARBA00022605,
KW ECO:0000256|PIRNR:PIRNR000381};
KW Cobalamin {ECO:0000256|ARBA:ARBA00022628, ECO:0000256|PIRNR:PIRNR000381};
KW Cobalt {ECO:0000256|ARBA:ARBA00023285, ECO:0000256|PIRNR:PIRNR000381};
KW Metal-binding {ECO:0000256|ARBA:ARBA00022723,
KW ECO:0000256|PIRNR:PIRNR000381};
KW Methionine biosynthesis {ECO:0000256|ARBA:ARBA00023167,
KW ECO:0000256|PIRNR:PIRNR000381};
KW Methyltransferase {ECO:0000256|ARBA:ARBA00022603,
KW ECO:0000256|PIRNR:PIRNR000381}; Repeat {ECO:0000256|ARBA:ARBA00022737};
KW S-adenosyl-L-methionine {ECO:0000256|ARBA:ARBA00022691,
KW ECO:0000256|PIRNR:PIRNR000381};
KW Transferase {ECO:0000256|ARBA:ARBA00022679, ECO:0000256|PIRNR:PIRNR000381};
KW Zinc {ECO:0000256|ARBA:ARBA00022833, ECO:0000256|PIRNR:PIRNR000381}.
FT DOMAIN 1..320
FT /note="Hcy-binding"
FT /evidence="ECO:0000259|PROSITE:PS50970"
FT DOMAIN 351..611
FT /note="Pterin-binding"
FT /evidence="ECO:0000259|PROSITE:PS50972"
FT DOMAIN 642..736
FT /note="B12-binding N-terminal"
FT /evidence="ECO:0000259|PROSITE:PS51337"
FT DOMAIN 744..879
FT /note="B12-binding"
FT /evidence="ECO:0000259|PROSITE:PS51332"
FT DOMAIN 895..1219
FT /note="AdoMet activation"
FT /evidence="ECO:0000259|PROSITE:PS50974"
FT BINDING 242
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-1,
FT ECO:0000256|PROSITE-ProRule:PRU00333"
FT BINDING 305
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-1,
FT ECO:0000256|PROSITE-ProRule:PRU00333"
FT BINDING 306
FT /ligand="Zn(2+)"
FT /ligand_id="ChEBI:CHEBI:29105"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-1,
FT ECO:0000256|PROSITE-ProRule:PRU00333"
FT BINDING 686
FT /ligand="methylcob(III)alamin"
FT /ligand_id="ChEBI:CHEBI:28115"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 754..758
FT /ligand="methylcob(III)alamin"
FT /ligand_id="ChEBI:CHEBI:28115"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 757
FT /ligand="methylcob(III)alamin"
FT /ligand_id="ChEBI:CHEBI:28115"
FT /ligand_part="Co"
FT /ligand_part_id="ChEBI:CHEBI:27638"
FT /note="axial binding residue"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-1"
FT BINDING 802
FT /ligand="methylcob(III)alamin"
FT /ligand_id="ChEBI:CHEBI:28115"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 806
FT /ligand="methylcob(III)alamin"
FT /ligand_id="ChEBI:CHEBI:28115"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 858
FT /ligand="methylcob(III)alamin"
FT /ligand_id="ChEBI:CHEBI:28115"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 944
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 1129
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 1184..1185
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
SQ SEQUENCE 1219 AA; 135303 MW; 7506EE46C40A9CD8 CRC64;
MNIREELEKR ILIIDGAMGT MIQRYVLTEE DFRGERFKDH PCDVKGNNDL LNLTRPDIIK
AIHTEYLKAG TDIIETNTFS TQRISLADYQ MEELDYEMSF EGAKIAKEAV DEFMAANPDR
KCFVAGAVGP TNRTLSISPD VNDPGFRAIT FDELVDAYDQ QVRGLVDGGA DLLLIETIFD
TLNAKAAIFS IKKYEAEIGR KIEIMISGTI TDASGRTLSG QTAEAFLNSV IHANPLSIGF
NCALGAKDMR PHIEELSAKA PCYVSAYPNA GLPNEFGAYD EMPHETAHLV GDFIQHGFVN
IVGGCCGTTP DHIGCIAAKA KNVAPRTIPH LEPYMRLSGL EPVTITPESI FVNIGERTNI
TGSPKFSKLI LGGDFEAALT VARQQVEGGA QVIDVNMDEG MIDSEASMTK FLNLIASEPD
ISKLPIMVDS SKWTVIEAGL KCLQGKGIVN SISLKEGEEK FRESARKIMT YGAAVVVMAF
DEQGQADNFE RRKEICKRSY DILVDEIGFP PQDIIFDPNI LTVATGLEEH NNYAVDFINA
TRWIKENLPY AKVSGGVSNI SFSFRGNNTV REAMHSAFLY HAIQAGLDMG IVNAGMLEVY
QEIPPELLVL VEDVLLNRRD DATERLVEFA DTIKSKGKEI VRDEEWRKNP VEERLSHALV
KGIIEYLDDD VEEARQKYAR PIQVIEGPLM DGMNIVGDLF GAGKMFLPQV VKSARVMKKA
VAYLLPFIEQ EKLDNPDQDQ NSSAGRILMA TVKGDVHDIG KNIVGVVLAC NNFEIVDMGV
MVPAQDIIKK AKEINADIIG LSGLITPSLD EMVHFAKEME REGFTIPLMI GGATTSRIHA
AVKVAPNYSG PAIHVLDASR SVTVASTLMN KDTREEYIAG IRAEYDKARE AHLNKRSDKR
FKTIEEARKD NFKIDPALVA PAPKFTGTQV FENYPLEELV PYIDWTPFFQ TWELRGSYPR
ILEDKVVGDE AKKLFADAQT LLKRIVDEKL LTAKAVIGFW PANAVGDDIV LNVEGKEVVI
HTLRQQAEKT ADQPYYALSD FVAQKETGVP DYFGGFALTT GIGCDELVAE FEAVYDDYNS
IMAKALADRL AEAFAERMHE LVRKDYWGYA KDEILDNEAL IKEEYSGIRP APGYPACPEH
TEKGTLFELL DAEAKIGLRL TESYAMYPTA AVSGFYFAHP QSRYFGLGKI TKDQVEDYAV
RKNMPLEEVE RWLSPNLAY
//