ID A0A1J4NLC1_9GAMM Unreviewed; 1228 AA. AC A0A1J4NLC1; DT 15-FEB-2017, integrated into UniProtKB/TrEMBL. DT 15-FEB-2017, sequence version 1. DT 29-SEP-2021, entry version 30. DE RecName: Full=Methionine synthase {ECO:0000256|PIRNR:PIRNR000381}; DE EC=2.1.1.13 {ECO:0000256|PIRNR:PIRNR000381}; DE AltName: Full=5-methyltetrahydrofolate--homocysteine methyltransferase {ECO:0000256|PIRNR:PIRNR000381}; GN ORFNames=BK820_02005 {ECO:0000313|EMBL:OIJ39084.1}; OS Acinetobacter sp. LCT-H3. OC Bacteria; Proteobacteria; Gammaproteobacteria; Pseudomonadales; OC Moraxellaceae; Acinetobacter. OX NCBI_TaxID=1914307 {ECO:0000313|EMBL:OIJ39084.1, ECO:0000313|Proteomes:UP000186913}; RN [1] {ECO:0000313|EMBL:OIJ39084.1, ECO:0000313|Proteomes:UP000186913} RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=LCT-H3 {ECO:0000313|EMBL:OIJ39084.1, RC ECO:0000313|Proteomes:UP000186913}; RA Huang B.; RT "Draft genome sequence of strain LCT isolated from the Shenzhou X RT spacecraft of China."; 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|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:PIRSR000381-2}; 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}. CC -!- CAUTION: The sequence shown here is derived from an EMBL/GenBank/DDBJ CC whole genome shotgun (WGS) entry which is preliminary data. CC {ECO:0000313|EMBL:OIJ39084.1}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; MODX01000002; OIJ39084.1; -; Genomic_DNA. DR RefSeq; WP_071319950.1; NZ_MODX01000002.1. DR EnsemblBacteria; OIJ39084; OIJ39084; BK820_02005. DR UniPathway; UPA00051; UER00081. DR Proteomes; UP000186913; 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 Gene3D; 1.10.1240.10; -; 1. DR Gene3D; 3.10.196.10; -; 1. DR Gene3D; 3.20.20.20; -; 1. DR Gene3D; 3.20.20.330; -; 1. DR InterPro; IPR003759; Cbl-bd_cap. DR InterPro; IPR006158; Cobalamin-bd. DR InterPro; IPR036724; Cobalamin-bd_sf. DR InterPro; IPR011005; Dihydropteroate_synth-like. 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 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; SSF47644; SSF47644; 1. DR SUPFAM; SSF51717; SSF51717; 1. DR SUPFAM; SSF52242; SSF52242; 1. DR SUPFAM; SSF56507; SSF56507; 1. DR SUPFAM; SSF82282; SSF82282; 1. DR TIGRFAMs; TIGR02082; metH; 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 4..322 FT /note="Hcy-binding" FT /evidence="ECO:0000259|PROSITE:PS50970" FT DOMAIN 353..614 FT /note="Pterin-binding" FT /evidence="ECO:0000259|PROSITE:PS50972" FT DOMAIN 651..745 FT /note="B12-binding N-terminal" FT /evidence="ECO:0000259|PROSITE:PS51337" FT DOMAIN 747..883 FT /note="B12-binding" FT /evidence="ECO:0000259|PROSITE:PS51332" FT DOMAIN 899..1228 FT /note="AdoMet activation" FT /evidence="ECO:0000259|PROSITE:PS50974" FT REGION 835..836 FT /note="Cobalamin-binding" FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2" FT REGION 1190..1191 FT /note="S-adenosyl-L-methionine binding" FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2" FT METAL 244 FT /note="Zinc" FT /evidence="ECO:0000256|PIRSR:PIRSR000381-1, FT ECO:0000256|PROSITE-ProRule:PRU00333" FT METAL 307 FT /note="Zinc" FT /evidence="ECO:0000256|PIRSR:PIRSR000381-1, FT ECO:0000256|PROSITE-ProRule:PRU00333" FT METAL 308 FT /note="Zinc" FT /evidence="ECO:0000256|PIRSR:PIRSR000381-1, FT ECO:0000256|PROSITE-ProRule:PRU00333" FT METAL 760 FT /note="Cobalt (cobalamin axial ligand)" FT /evidence="ECO:0000256|PIRSR:PIRSR000381-1" FT BINDING 805 FT /note="Cobalamin" FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2" FT BINDING 949 FT /note="S-adenosyl-L-methionine" FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2" FT BINDING 1135 FT /note="S-adenosyl-L-methionine; via carbonyl oxygen" FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2" FT BINDING 1139 FT /note="Cobalamin; via carbonyl oxygen" FT /evidence="ECO:0000256|PIRSR:PIRSR000381-2" SQ SEQUENCE 1228 AA; 135279 MW; 17BD4F3C873C5626 CRC64; MSTLATLKEL LAKRILIIDG AMGTMIQRHK LEEADYRGER FADWAYDLKG NNDLLVLTQP HIIQGIHEAY LEAGADIIET NTFNGTRVSM SDYHMEDLVP EINREAARLA KEACAKYSTP EKPRFVAGVI GPTSRTTSIS PNVNDPAFRN ITFDALKVDY IESTKALIEG GADIILIETV FDTLNAKAAI FAVKEVFKEI GYELPIMISG TITDASGRTL TGQTAEAFWN SMRHAEPISI GFNCALGADA MRPHVKTISD VADTFVSAHP NAGLPNAFGG YDETPEETAA FIKEFAESGL INITGGCCGT TPDHIRAIAQ AVEGIAPRQI PEIEPACRLS GLEPFNITKD SLFVNVGERT NVTGSKKFLR LIKEENFTEA LDVARQQVEA GAQIIDINMD EGMLDSQAAM VHFLNLIASE PDISRVPIML DSSKWEIIEA GLKCVQGKAV VNSISLKEGY DEFVERARLC RQYGAAVIVM AFDENGQADT AERKKEICKR SYDVLVNEVG FPSEDIIFDP NVFAVATGIE EHNNYGVDFI EATGWIKQNL PNAMISGGIS NVSFSFRGNE PVREAIHAVF LYHAIQKGLT MGIVNAGQLA IYDDIDAELK EAVEDVVLNR NQGESGQEAT EKLLTIAEKY RGQAGAQKAE ENLEWRNESV EKRLEYALVK GITTYIDQDT EEARLKSARP LDVIEGPLMA GMNVVGDLFG AGKMFLPQVV KSARVMKQAV AWLNPFIEAE KTQGEAKGKI LLATVKGDVH DIGKNIVGVV LGCNGYDIVD LGVMVPCEKI LQTAIDEKVD IIGLSGLITP SLDEMVFVAK EMQRKGFNIP LMIGGATTSK AHTAVKIAPQ YQNDGVFYTA DASRAVGVTT QLLSAEMKPQ LMADYAADYE KIRTRLANKQ PKAAKLSYKE SVENGFKIDF DKNAPVKPNF IGSQTFTNYP LETLVEYFDW TPFFISWSLA GKFPKILEDE VVGEAARDLY AQAQAMLKNI IDNKRFDARA TFSIYPANRT GSDTVAVTDE AGNVTHTFEH LRQQSDKVTG KANYSLADFI APKDVAQDYL GGFTVSIFGA EELSQEYKAK GDDYNAIMVQ ALGDRFAEAF AEHLHQRIRK EFWGYQPNES LDNEALIKEK YVGIRPAPGY PACPEHSEKA PLFDWLGTTE KMGTYLTSSF AMWPPSSVSG FYYANPETEY FNVGKISGDQ LEDYAKRKGW TLDEAKRWLA PNLDDSVV //