Reviewed, UniProtKB/Swiss-Prot Q50755 (HDRB_METTM)

Names and origin

Protein names

Recommended name:
    CoB--CoM heterodisulfide reductase subunit B
    EC=1.8.98.1

Gene names

Name:

hdrB

Organism

Methanobacterium thermoautotrophicum (strain Marburg / DSM 2133)

Taxonomic identifier

79929 [NCBI]

Taxonomic lineage

Archaea › Euryarchaeota › Methanobacteria › Methanobacteriales › Methanobacteriaceae › Methanothermobacter

Protein attributes

Sequence length	302 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Part of a complex that catalyzes the reversible reduction of CoM-S-S-CoB to the thiol-coenzymes H-S-CoM (coenzyme M) and H-S-CoB (coenzyme B). HdrB may have a function in energy transduction. Ref.2
Catalytic activity	Coenzyme B + coenzyme M + methanophenazine = N-(7-((2-sulfoethyl)dithio)heptanoyl)-O(3)-phospho-L-threonine + dihydromethanophenazine.
Pathway	Cofactor metabolism; coenzyme M-coenzyme B heterodisulfide reduction; coenzyme B and coenzyme M from coenzyme M-coenzyme B heterodisulfide: step 1/1.
Subunit structure	The heterodisulfide reductase is composed of three subunits; hdrA, hdrB and hdrC. It forms a complex with the F420-non-reducing hydrogenase (Mvh), which provides the reducing equivalents to the heterodisulfide reductase. Ref.2
Sequence similarities	Belongs to the hdrB family.

Ontologies

Keywords
Biological process	Methanogenesis
Molecular function	Oxidoreductase
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological process	cofactor metabolic process Inferred from electronic annotation. Source: InterPro methanogenesis Ref.2 Inferred from direct assay. Source: UniProtKB oxidation reduction Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	membrane Ref.1 Non-traceable author statement. Source: UniProtKB
Molecular function	CoB--CoM heterodisulfide reductase activity Ref.2 Inferred from direct assay. Source: UniProtKB
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 302	302	CoB--CoM heterodisulfide reductase subunit B		PRO_0000150070

Sequences

	Sequence		Length	Mass (Da)
	Q50755-1 [UniParc]. Last modified November 1, 1996. Version 1. Checksum: 6D3FAC11C1969B64	FASTA	302	33,458
	10 20 30 40 50 60 MEIAYFLGCI MNNRYPGIEK ATRVLFDKLG IELKDMEGAS CCPAPGVFGS FDKTTWAAIA 70 80 90 100 110 120 ARNITIAEDM GADIMTECNG CFGSLFETNH LLKEDEEMKA KINEILKETG REYKGEVNVR 130 140 150 160 170 180 HFAEVLYNDV GLDKLSELVE KPLNLNVAVH YGCHFLKPSD EINIDNPERP TILDEIVEVT 190 200 210 220 230 240 GAKSVEYKDK MMCCGAGGGV RSRDLDVALD FTREKLTNMK EAGVDAIVNV CPFCHLQFDV 250 260 270 280 290 300 GQMEIKDKFG EEFDIPVLHL AQLLGLAMGL PKEDLVVDAH QVCVDECLEK LEELDRLAPG SG

References

[1]	"The heterodisulfide reductase from Methanobacterium thermoautotrophicum contains sequence motifs characteristic of pyridine-nucleotide-dependent thioredoxin reductases." Hedderich R., Koch J., Linder D., Thauer R.K. Eur. J. Biochem. 225:253-261(1994) [PubMed: 7925445] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], PROTEIN SEQUENCE OF 1-33.
[2]	"Purification and properties of heterodisulfide reductase from Methanobacterium thermoautotrophicum (strain Marburg)." Hedderich R., Berkessel A., Thauer R.K. Eur. J. Biochem. 193:255-261(1990) [PubMed: 2121478] [Abstract] Cited for: FUNCTION, SUBUNIT.
[3]	"H2: heterodisulfide oxidoreductase complex from Methanobacterium thermoautotrophicum. Composition and properties." Setzke E., Hedderich R., Heiden S., Thauer R.K. Eur. J. Biochem. 220:139-148(1994) [PubMed: 8119281] [Abstract] Cited for: ASSOCIATION WITH F420-NON-REDUCING HYDROGENASE, PROTEIN SEQUENCE OF 1-27.
[4]	"Physiological role of the F420-non-reducing hydrogenase (Mvh) from Methanothermobacter marburgensis." Stojanowic A., Mander G.J., Duin E.C., Hedderich R. Arch. Microbiol. 180:194-203(2003) [PubMed: 12856108] [Abstract] Cited for: ASSOCIATION WITH F420-NON-REDUCING HYDROGENASE.

Cross-references

Sequence databases
EMBLGenBankDDBJ	X81133 Genomic DNA. Translation: CAA57038.1.
PIR	S78509.
3D structure databases
ModBase	Search...
Family and domain databases
InterPro	IPR017678. CoB/CoM_hetero-S_Rdtase_bsu. IPR004017. Cys_rich_region. [Graphical view]
Pfam	PF02754. CCG. 2 hits. [Graphical view]
TIGRFAMs	TIGR03288. CoB_CoM_SS_B. 1 hit.
ProtoNet	Search...

Entry information

Entry name

HDRB_METTM

Accession

Primary (citable) accession number: Q50755

Entry history

Integrated into UniProtKB/Swiss-Prot:	January 16, 2004
Last sequence update:	November 1, 1996
Last modified:	September 22, 2009
This is version 43 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

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