Reviewed, UniProtKB/Swiss-Prot O27236 (MCRB_METTH)

Names and origin

Protein names

Recommended name:
    Methyl-coenzyme M reductase I subunit beta
      Short name=MCR I beta
    EC=2.8.4.1
Alternative name(s):
    Coenzyme-B sulfoethylthiotransferase beta

Gene names

Name:	mcrB
Ordered Locus Names:	MTH_1168

Organism

Methanobacterium thermoautotrophicum [Complete proteome] [HAMAP]

Taxonomic identifier

187420 [NCBI]

Taxonomic lineage

Archaea › Euryarchaeota › Methanobacteria › Methanobacteriales › Methanobacteriaceae › Methanothermobacter

Protein attributes

Sequence length	443 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Reduction of methyl-coenzyme M (2-(methylthio) ethanesulfonic acid) with 7-mercaptoheptanoylthreonine phosphate to methane and an heterodisulfide.
Catalytic activity	2-(methylthio)ethanesulfonate (methyl-CoM) + N-(7-mercaptoheptanoyl)threonine 3-O-phosphate (coenzyme B) = CoM-S-S-CoB + methane.
Cofactor	Binds 2 coenzyme F430 noncovalently per hexamer. Coenzyme F430 is a yellow nickel porphinoid By similarity.
Pathway	One-carbon metabolism; methyl-coenzyme M reduction; methane from methyl-coenzyme M: step 1/1.
Subunit structure	Hexamer of two alpha, two beta, and two gamma chains.
Developmental stage	There are two MCR complexes in this bacteria. MCR II is expressed in the early growth phase. Late growth cells contains mostly MCR I.

Ontologies

Keywords
Biological process	Methanogenesis
Molecular function	Transferase
Technical term	Complete proteome Direct protein sequencing
Gene Ontology (GO)
Biological process	methanogenesis Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	coenzyme-B sulfoethylthiotransferase activity Inferred from electronic annotation. Source: EC
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Initiator methionine	1	1	Removed Ref.3
	Chain	2 – 443	442	Methyl-coenzyme M reductase I subunit beta		PRO_0000147467
Experimental info
	Sequence conflict	82	1	A → C in AAA73441. Ref.1

Sequences

	Sequence		Length	Mass (Da)
	O27236-1 [UniParc]. Last modified January 23, 2007. Version 3. Checksum: 132DFCD54BBB734E	FASTA	443	47,224
	10 20 30 40 50 60 MAKFEDKVDL YDDRGNLVEE QVPLEALSPL RNPAIKSIVQ GIKRTVAVNL EGIENALKTA 70 80 90 100 110 120 KVGGPACKIM GRELDLDIVG NAESIAAAAK EMIQVTEDDD TKVELLGGGK RALVQVPSAR 130 140 150 160 170 180 FDVAAEYSAA PLVTATAFVQ AIINEFDVSM YDANMVKAAV LGRYPQSVEY MGANIATMLD 190 200 210 220 230 240 IPQKLEGPGY ALRNIMVNHV VAATLKNTLQ AAALSTILEQ TAMFEMGDAV GAFERMHLLG 250 260 270 280 290 300 LAYQGMNADN LVFDLVKANG KEGTVGSVIA DLVERALEDG VIKVEKELTD YKVYGTDDLA 310 320 330 340 350 360 MWNAYAAAGL MAATMVNQGA ARAAQGVSST LLYYNDLIEF ETGLPGVDFG KVEGTAVGFS 370 380 390 400 410 420 FFSHSIYGGG GPGIFNGNHI VTRHSKGFAI PCVAAAMALD AGTQMFSPEA TSGLIKEVFS 430 440 QVDEFREPLK YVVEAAAEIK NEI

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Growth phase-dependent transcription of the genes that encode the two methyl coenzyme M reductase isoenzymes and N5-methyltetrahydromethanopterin:coenzyme M methyltransferase in Methanobacterium thermoautotrophicum delta H." Pihl T.D., Sharma S., Reeve J.N. J. Bacteriol. 176:6384-6391(1994) [PubMed: 7929010] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: Delta H.
[2]	"Complete genome sequence of Methanobacterium thermoautotrophicum deltaH: functional analysis and comparative genomics." Smith D.R., Doucette-Stamm L.A., Deloughery C., Lee H.-M., Dubois J., Aldredge T., Bashirzadeh R., Blakely D., Cook R., Gilbert K., Harrison D., Hoang L., Keagle P., Lumm W., Pothier B., Qiu D., Spadafora R., Vicare R. , Wang Y., Wierzbowski J., Gibson R., Jiwani N., Caruso A., Bush D., Safer H., Patwell D., Prabhakar S., McDougall S., Shimer G., Goyal A., Pietrovski S., Church G.M., Daniels C.J., Mao J.-I., Rice P., Noelling J., Reeve J.N. J. Bacteriol. 179:7135-7155(1997) [PubMed: 9371463] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: Delta H.
[3]	"Two genetically distinct methyl-coenzyme M reductases in Methanobacterium thermoautotrophicum strain Marburg and delta H." Rospert S., Linder D., Ellermann J., Thauer R.K. Eur. J. Biochem. 194:871-877(1990) [PubMed: 2269306] [Abstract] Cited for: PROTEIN SEQUENCE OF 2-21. Strain: Delta H.

Cross-references

Sequence databases
EMBLGenBankDDBJ	U10036 Genomic DNA. Translation: AAA73441.1. AE000666 Genomic DNA. Translation: AAB85657.1. Different initiation.
PIR	F69022.
RefSeq	NP_276296.1.
3D structure databases
HSSP	HSSP built from PDB template 1HBN based on UniProtKB P11560.
SMR	O27236. Positions 2-443.
ModBase	Search...
Protein-protein interaction databases
STRING	O27236.
Genome annotation databases
GeneID	1471576.
GenomeReviews	Gene locus MTH_1168 in contig AE000666_GR.
KEGG	mth:MTH1168.
NMPDR	fig|187420.1.peg.1151.
Organism-specific databases
CMR	Search...
Phylogenomic databases
HOGENOM	O27236.
Enzyme and pathway databases
BioCyc	MTHE187420:MTH1168-MON.
BRENDA	2.8.4.1. 270.
Family and domain databases
InterPro	IPR008924. Me_CoM_Rdtase_asu/bsu_C. IPR003179. Me_CoM_Rdtase_bsu. [Graphical view]
Gene3D	G3DSA:1.20.840.10. MCR_a/b_chain_a-bundle. 2 hits.
Pfam	PF02241. MCR_beta. 1 hit. PF02783. MCR_beta_N. 1 hit. [Graphical view]
PIRSF	PIRSF000263. Meth_CoM_rd_beta. 1 hit.
TIGRFAMs	TIGR03257. met_CoM_red_bet. 1 hit.
ProtoNet	Search...

Entry information

Entry name

MCRB_METTH

Accession

Primary (citable) accession number: O27236
Secondary accession number(s): Q50489

Entry history

Integrated into UniProtKB/Swiss-Prot:	May 30, 2000
Last sequence update:	January 23, 2007
Last modified:	September 22, 2009
This is version 71 of the entry and version 3 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HAMAP (High-quality Automated and Manual Annotation of microbial Proteomes)