ID A0A1H7FB19_9GAMM Unreviewed; 1269 AA.
AC A0A1H7FB19;
DT 22-NOV-2017, integrated into UniProtKB/TrEMBL.
DT 22-NOV-2017, sequence version 1.
DT 27-MAR-2024, entry version 32.
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=SAMN04488129_10184 {ECO:0000313|EMBL:SEK23296.1};
OS Halomonas daqiaonensis.
OC Bacteria; Pseudomonadota; Gammaproteobacteria; Oceanospirillales;
OC Halomonadaceae; Halomonas.
OX NCBI_TaxID=650850 {ECO:0000313|EMBL:SEK23296.1, ECO:0000313|Proteomes:UP000198807};
RN [1] {ECO:0000313|EMBL:SEK23296.1, ECO:0000313|Proteomes:UP000198807}
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=CGMCC 1.9150 {ECO:0000313|EMBL:SEK23296.1,
RC ECO:0000313|Proteomes:UP000198807};
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; FOBC01000001; SEK23296.1; -; Genomic_DNA.
DR AlphaFoldDB; A0A1H7FB19; -.
DR STRING; 650850.SAMN04488129_10184; -.
DR UniPathway; UPA00051; UER00081.
DR Proteomes; UP000198807; 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 39..358
FT /note="Hcy-binding"
FT /evidence="ECO:0000259|PROSITE:PS50970"
FT DOMAIN 389..650
FT /note="Pterin-binding"
FT /evidence="ECO:0000259|PROSITE:PS50972"
FT DOMAIN 682..776
FT /note="B12-binding N-terminal"
FT /evidence="ECO:0000259|PROSITE:PS51337"
FT DOMAIN 779..914
FT /note="B12-binding"
FT /evidence="ECO:0000259|PROSITE:PS51332"
FT DOMAIN 930..1269
FT /note="AdoMet activation"
FT /evidence="ECO:0000259|PROSITE:PS50974"
FT BINDING 280
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 343
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 344
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 726
FT /ligand="methylcob(III)alamin"
FT /ligand_id="ChEBI:CHEBI:28115"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 789..793
FT /ligand="methylcob(III)alamin"
FT /ligand_id="ChEBI:CHEBI:28115"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 792
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 837
FT /ligand="methylcob(III)alamin"
FT /ligand_id="ChEBI:CHEBI:28115"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 841
FT /ligand="methylcob(III)alamin"
FT /ligand_id="ChEBI:CHEBI:28115"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 893
FT /ligand="methylcob(III)alamin"
FT /ligand_id="ChEBI:CHEBI:28115"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 980
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 1176
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
FT BINDING 1231..1232
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2"
SQ SEQUENCE 1269 AA; 140025 MW; A3D1D43F19B90731 CRC64;
MPAAQPLDKT PQAPRCWLAP LMPTLEIDRP MAAVPTALTA TLTDRLNERI LMLDGGMGTM
LQNAGLSEQE FRGERFADWP SDLKGNNDLL ALTCPELVTR IHRQYLEAGA DIVETNTFNS
TRLSQSDYGM EALVPELNRE SARLARAVCD AVAEETGVPR YVAGVLGPTS RTASLSPDVN
DPSKRNVTFD ALRENYYEAA EALIEGGADL ILIETIFDTL NAKAAIYALE EVFAARGERL
PVMISGTITD ASGRTLSGQT TEAFWNSVRH ARPLSIGLNC ALGAEDLRPY VEELASKADT
FVSAHPNAGL PNEFGEYDQT PEEMAAIVAE FAESGLVNII GGCCGSAPEH IAAIHAAIQG
LAPRRVPERP RACRLSGLEP FNIDADSLFV NVGERTNVTG SARFKRLIVE EDYTTALDVA
LEQVENGAQI IDINMDEGML ESAEAMVHFL NLIAGEPDIA RVPIMIDSSK WEIIEAGLKC
VQGKAVVNSI SMKEGEDAFR EQATRCRRYG AAIIIMAFDE QGQADTFARK TEISRRAYRI
LVDELDFPPE DIIFDPNIFA IATGIEEHDN YAVDFIEATR WIRKHLPHAM VSGGVSNVSF
SFRGNNPVRE AIHSVFLYHA IRAGLTMGIV NAGQLAVYDD LPSELREAVE DVVLNRRSDS
TERLLELADK YKGDGSGPAR KEDLEWRSWA VEKRIEHALI KGVTAYIEED TELARQRAER
PIEVIEGPLM DGMNVVGDLF GDGKMFLPQV VKSARVMKQA VAYLIPYIEA EKSADSQAKG
KIVMATVKGD VHDIGKNIVG VVLQCNNYEV IDLGVMVSAE KILQTARDEN ADIIGLSGLI
TPSLDEMVHV AKEMQRQGFD LPLLIGGATT SKAHTAVKIE PGYEHPVIYV TDASRAVGVA
GKLLSPTLKP AYIDEIRADY DKVRERNAKR RPKAADLSYA EARKLKPVMD WDNYMPPQPA
ITGLEVFDDY DLEELVERLD WTPFFMSWQL AGKYPKILDD AKVGEAARNL FADAQAMLRK
LIDEKRVQAR GVIGLWPANS VDDDVIEVYA DESRSEVIER LHHIRQQTTK NRDGVCHSLA
DFIAPRYDVT GEPSGKPDWI GGFAVTTGHG VEALAEQYKA AGDDYNAILV QSLTDRLAEA
FAERLHERVR KEFWGYVPDE TLDNSAIIAE KYQGIRPAPG YPACPDHTEK ATLFRLLQAT
ENAGLELTEN FAMWPAAAVA GWYFSHPQSK YFSTGKITRD QVEALAERKG MTIEELERWL
APVLSYDPA
//
