ID MCRA_METVA Reviewed; 553 AA. AC P07961; DT 01-AUG-1988, integrated into UniProtKB/Swiss-Prot. DT 01-AUG-1988, sequence version 1. DT 13-SEP-2023, entry version 99. DE RecName: Full=Methyl-coenzyme M reductase subunit alpha; DE EC=2.8.4.1 {ECO:0000250|UniProtKB:P11558}; DE AltName: Full=Coenzyme-B sulfoethylthiotransferase alpha; GN Name=mcrA; OS Methanococcus vannielii. OC Archaea; Euryarchaeota; Methanomada group; Methanococci; Methanococcales; OC Methanococcaceae; Methanococcus. OX NCBI_TaxID=2187; RN [1] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA]. RX PubMed=16593847; DOI=10.1073/pnas.84.12.3992; RA Cram D.S., Sherf B.A., Libby R.T., Mattaliano R.J., Ramachandran K.L., RA Reeve J.N.; RT "Structure and expression of the genes, mcrBDCGA, which encode the subunits RT of component C of methyl coenzyme M reductase in Methanococcus vannielii."; RL Proc. Natl. Acad. Sci. U.S.A. 84:3992-3996(1987). CC -!- FUNCTION: Component of the methyl-coenzyme M reductase (MCR) I that CC catalyzes the reductive cleavage of methyl-coenzyme M (CoM-S-CH3 or 2- CC (methylthio)ethanesulfonate) using coenzyme B (CoB or 7- CC mercaptoheptanoylthreonine phosphate) as reductant which results in the CC production of methane and the mixed heterodisulfide of CoB and CoM CC (CoM-S-S-CoB). This is the final step in methanogenesis. CC {ECO:0000250|UniProtKB:P11558}. CC -!- CATALYTIC ACTIVITY: CC Reaction=coenzyme B + methyl-coenzyme M = coenzyme M-coenzyme B CC heterodisulfide + methane; Xref=Rhea:RHEA:12532, ChEBI:CHEBI:16183, CC ChEBI:CHEBI:58286, ChEBI:CHEBI:58411, ChEBI:CHEBI:58596; EC=2.8.4.1; CC Evidence={ECO:0000250|UniProtKB:P11558}; CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:12533; CC Evidence={ECO:0000250|UniProtKB:P11558}; CC -!- COFACTOR: CC Name=coenzyme F430; Xref=ChEBI:CHEBI:60540; CC Evidence={ECO:0000250|UniProtKB:P11558}; CC Note=Binds 2 coenzyme F430 non-covalently per MCR complex. Coenzyme CC F430 is a yellow nickel porphinoid. Methyl-coenzyme-M reductase is CC activated when the enzyme-bound coenzyme F430 is reduced to the Ni(I) CC oxidation state. {ECO:0000250|UniProtKB:P11558}; CC -!- PATHWAY: One-carbon metabolism; methyl-coenzyme M reduction; methane CC from methyl-coenzyme M: step 1/1. {ECO:0000250|UniProtKB:P11558}. CC -!- SUBUNIT: MCR is a hexamer of two alpha, two beta, and two gamma chains, CC forming a dimer of heterotrimers. {ECO:0000250|UniProtKB:P11558}. CC -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000250|UniProtKB:P11558}. CC -!- SIMILARITY: Belongs to the methyl-coenzyme M reductase alpha subunit CC family. {ECO:0000305}. 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; M16893; AAA72598.1; -; Genomic_DNA. DR PIR; E27793; E27793. DR AlphaFoldDB; P07961; -. DR SMR; P07961; -. DR UniPathway; UPA00646; UER00699. DR GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell. DR GO; GO:0050524; F:coenzyme-B sulfoethylthiotransferase activity; IEA:UniProtKB-EC. DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW. DR GO; GO:0015948; P:methanogenesis; IEA:UniProtKB-KW. DR Gene3D; 3.30.70.470; -; 1. DR Gene3D; 1.20.840.10; Methyl-coenzyme M reductase, alpha/beta subunit, C-terminal; 1. DR InterPro; IPR016212; Me_CoM_Rdtase_asu. DR InterPro; IPR008924; Me_CoM_Rdtase_asu/bsu_C. DR InterPro; IPR009047; Me_CoM_Rdtase_asu_C. DR InterPro; IPR003183; Me_CoM_Rdtase_asu_N. DR InterPro; IPR015811; Me_CoM_Rdtase_asu_N_sub1. DR InterPro; IPR015823; Me_CoM_Rdtase_asu_N_sub2. DR InterPro; IPR009024; Me_CoM_Rdtase_Fd-like_fold. DR NCBIfam; TIGR03256; met_CoM_red_alp; 1. DR Pfam; PF02249; MCR_alpha; 1. DR Pfam; PF02745; MCR_alpha_N; 1. DR PIRSF; PIRSF000262; MCR_alpha; 1. DR SUPFAM; SSF48081; Methyl-coenzyme M reductase alpha and beta chain C-terminal domain; 1. DR SUPFAM; SSF55088; Methyl-coenzyme M reductase subunits; 1. PE 3: Inferred from homology; KW Cytoplasm; Metal-binding; Methanogenesis; Methylation; Nickel; Transferase. FT CHAIN 1..553 FT /note="Methyl-coenzyme M reductase subunit alpha" FT /id="PRO_0000147460" FT BINDING 151 FT /ligand="coenzyme F430" FT /ligand_id="ChEBI:CHEBI:60540" FT /ligand_part="Ni" FT /ligand_part_id="ChEBI:CHEBI:28112" FT /note="axial binding residue" FT /evidence="ECO:0000250|UniProtKB:P11558" FT BINDING 229 FT /ligand="coenzyme B" FT /ligand_id="ChEBI:CHEBI:58596" FT /ligand_note="ligand shared between two alpha subunits" FT /note="in chain A" FT /evidence="ECO:0000250|UniProtKB:P11558" FT BINDING 260..261 FT /ligand="coenzyme B" FT /ligand_id="ChEBI:CHEBI:58596" FT /ligand_note="ligand shared between two alpha subunits" FT /note="in chain A" FT /evidence="ECO:0000250|UniProtKB:P11558" FT BINDING 274 FT /ligand="coenzyme B" FT /ligand_id="ChEBI:CHEBI:58596" FT /ligand_note="ligand shared between two alpha subunits" FT /note="in chain B" FT /evidence="ECO:0000250|UniProtKB:P11558" FT BINDING 336 FT /ligand="coenzyme M" FT /ligand_id="ChEBI:CHEBI:58319" FT /evidence="ECO:0000250|UniProtKB:P11558" FT BINDING 447 FT /ligand="coenzyme M" FT /ligand_id="ChEBI:CHEBI:58319" FT /evidence="ECO:0000250|UniProtKB:P11558" SQ SEQUENCE 553 AA; 60838 MW; 7B91F2DDA4B98489 CRC64; MEAEKRLFLK ALKEKFEEDP KEKYTKFYTY GGWEQSVRKR EFVAANEKVL AEKRQGVPLY NPDIGVPLGQ RKLMPYKLSG TDSYCEGDDL HFMNNAAIQQ LWDDIRRTVV VGMDTAHSVL EKRLGVEVTP ETINEYMHTI NHALSGGAVV QEHMVEVHPS LAWDSYARIF TGDDELAAEL DSRFLIDINK LFPAEQAEAL KKAIGKKTYQ VSRVPSLVGR VCDGGTISRW SAMQIGMSFI TAYKLCAGEA ATADFSYASK HADVIQMGNA LPGRRARGPN EPGGIQFGIL SDVVQTTRVS DDPVEQSLEV VAAGAALYDQ IWLGAYMSGG VGFTQYATAA YTDDILDDFS YYALDYVEKK YGRMGTKATM DVVEDIASEV TLYSLEQYDE YPALLEDHFG GSQRAAVAAA ASGIGVCMAT GNSNAGVNGW YLSQILHKEY HSRLGFYGYD LQDQCGASNS LAIRNDESAP LELRGPNYPN YAMNVGHQGE YAGIAQAAHS ARGDAFAMSA LIKVAFADPM LVFDFSKPRK EFARGALREF DAAGERDVIL PAK //