ID   MTRB_METAC              Reviewed;         108 AA.
AC   Q8TU02;
DT   28-NOV-2003, integrated into UniProtKB/Swiss-Prot.
DT   01-JUN-2002, sequence version 1.
DT   25-MAY-2022, entry version 101.
DE   RecName: Full=Tetrahydromethanopterin S-methyltransferase subunit B {ECO:0000255|HAMAP-Rule:MF_01094};
DE            EC=2.1.1.86 {ECO:0000255|HAMAP-Rule:MF_01094};
DE   AltName: Full=N5-methyltetrahydromethanopterin--coenzyme M methyltransferase subunit B {ECO:0000255|HAMAP-Rule:MF_01094};
GN   Name=mtrB {ECO:0000255|HAMAP-Rule:MF_01094}; OrderedLocusNames=MA_0273;
OS   Methanosarcina acetivorans (strain ATCC 35395 / DSM 2834 / JCM 12185 /
OS   C2A).
OC   Archaea; Euryarchaeota; Stenosarchaea group; Methanomicrobia;
OC   Methanosarcinales; Methanosarcinaceae; Methanosarcina.
OX   NCBI_TaxID=188937;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC 35395 / DSM 2834 / JCM 12185 / C2A;
RX   PubMed=11932238; DOI=10.1101/gr.223902;
RA   Galagan J.E., Nusbaum C., Roy A., Endrizzi M.G., Macdonald P., FitzHugh W.,
RA   Calvo S., Engels R., Smirnov S., Atnoor D., Brown A., Allen N., Naylor J.,
RA   Stange-Thomann N., DeArellano K., Johnson R., Linton L., McEwan P.,
RA   McKernan K., Talamas J., Tirrell A., Ye W., Zimmer A., Barber R.D.,
RA   Cann I., Graham D.E., Grahame D.A., Guss A.M., Hedderich R.,
RA   Ingram-Smith C., Kuettner H.C., Krzycki J.A., Leigh J.A., Li W., Liu J.,
RA   Mukhopadhyay B., Reeve J.N., Smith K., Springer T.A., Umayam L.A.,
RA   White O., White R.H., de Macario E.C., Ferry J.G., Jarrell K.F., Jing H.,
RA   Macario A.J.L., Paulsen I.T., Pritchett M., Sowers K.R., Swanson R.V.,
RA   Zinder S.H., Lander E., Metcalf W.W., Birren B.;
RT   "The genome of Methanosarcina acetivorans reveals extensive metabolic and
RT   physiological diversity.";
RL   Genome Res. 12:532-542(2002).
CC   -!- FUNCTION: Part of a complex that catalyzes the formation of methyl-
CC       coenzyme M and tetrahydromethanopterin from coenzyme M and methyl-
CC       tetrahydromethanopterin. This is an energy-conserving, sodium-ion
CC       translocating step. {ECO:0000255|HAMAP-Rule:MF_01094}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=5-methyl-5,6,7,8-tetrahydromethanopterin + coenzyme M + 2
CC         Na(+)(in) = 5,6,7,8-tetrahydromethanopterin + methyl-coenzyme M + 2
CC         Na(+)(out); Xref=Rhea:RHEA:53492, ChEBI:CHEBI:29101,
CC         ChEBI:CHEBI:58103, ChEBI:CHEBI:58116, ChEBI:CHEBI:58286,
CC         ChEBI:CHEBI:58319; EC=2.1.1.86; Evidence={ECO:0000255|HAMAP-
CC         Rule:MF_01094};
CC   -!- PATHWAY: One-carbon metabolism; methanogenesis from CO(2); methyl-
CC       coenzyme M from 5,10-methylene-5,6,7,8-tetrahydromethanopterin: step
CC       2/2. {ECO:0000255|HAMAP-Rule:MF_01094}.
CC   -!- SUBUNIT: The complex is composed of 8 subunits; MtrA, MtrB, MtrC, MtrD,
CC       MtrE, MtrF, MtrG and MtrH. {ECO:0000255|HAMAP-Rule:MF_01094}.
CC   -!- SUBCELLULAR LOCATION: Cell membrane {ECO:0000255|HAMAP-Rule:MF_01094};
CC       Single-pass membrane protein {ECO:0000255|HAMAP-Rule:MF_01094}.
CC   -!- SIMILARITY: Belongs to the MtrB family. {ECO:0000255|HAMAP-
CC       Rule:MF_01094}.
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DR   EMBL; AE010299; AAM03726.1; -; Genomic_DNA.
DR   RefSeq; WP_011020331.1; NC_003552.1.
DR   AlphaFoldDB; Q8TU02; -.
DR   STRING; 188937.MA_0273; -.
DR   EnsemblBacteria; AAM03726; AAM03726; MA_0273.
DR   GeneID; 1472165; -.
DR   KEGG; mac:MA_0273; -.
DR   HOGENOM; CLU_171544_0_0_2; -.
DR   InParanoid; Q8TU02; -.
DR   OMA; TNMVYGF; -.
DR   OrthoDB; 114178at2157; -.
DR   UniPathway; UPA00640; UER00698.
DR   Proteomes; UP000002487; Chromosome.
DR   GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR   GO; GO:0005886; C:plasma membrane; IEA:UniProtKB-SubCell.
DR   GO; GO:0030269; F:tetrahydromethanopterin S-methyltransferase activity; IEA:UniProtKB-UniRule.
DR   GO; GO:0019386; P:methanogenesis, from carbon dioxide; IEA:UniProtKB-UniPathway.
DR   GO; GO:0032259; P:methylation; IEA:UniProtKB-KW.
DR   GO; GO:0006730; P:one-carbon metabolic process; IEA:UniProtKB-UniRule.
DR   HAMAP; MF_01094; MtrB; 1.
DR   InterPro; IPR008690; MtrB_MeTrfase.
DR   Pfam; PF05440; MtrB; 1.
DR   PIRSF; PIRSF005518; MtrB; 1.
DR   TIGRFAMs; TIGR04166; methano_MtrB; 1.
PE   3: Inferred from homology;
KW   Cell membrane; Membrane; Methanogenesis; Methyltransferase;
KW   One-carbon metabolism; Reference proteome; Transferase; Transmembrane;
KW   Transmembrane helix.
FT   CHAIN           1..108
FT                   /note="Tetrahydromethanopterin S-methyltransferase subunit
FT                   B"
FT                   /id="PRO_0000147512"
FT   TRANSMEM        80..100
FT                   /note="Helical"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01094"
SQ   SEQUENCE   108 AA;  11909 MW;  C9007D9B5F296534 CRC64;
     MSMIRIAPEV HLVMDPDTAV VAEEREDSIL YSMDPVFERM DKLDGIAEDL LNSLSPSKPL
     LNSWPGRENT SYMAGIYGNA FYGIVVGLAF SGLLALIIFI QRLIEGGM