Q49605 · MCRA_METKA
- ProteinMethyl-coenzyme M reductase I subunit alpha
- GenemcrA
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids553 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score3/5
Function
function
Component of the methyl-coenzyme M reductase (MCR) I that catalyzes the reductive cleavage of methyl-coenzyme M (CoM-S-CH3 or 2-(methylthio)ethanesulfonate) using coenzyme B (CoB or 7-mercaptoheptanoylthreonine phosphate) as reductant which results in the production of methane and the mixed heterodisulfide of CoB and CoM (CoM-S-S-CoB). This is the final step in methanogenesis.
Catalytic activity
- coenzyme B + methyl-coenzyme M = coenzyme M-coenzyme B heterodisulfide + methaneThis reaction proceeds in the forward direction.
Cofactor
Note: Binds 2 coenzyme F430 non-covalently per MCR complex. Coenzyme F430 is a yellow nickel porphinoid (PubMed:11023796).
Methyl-coenzyme-M reductase is activated when the enzyme-bound coenzyme F430 is reduced to the Ni(I) oxidation state (By similarity).
Methyl-coenzyme-M reductase is activated when the enzyme-bound coenzyme F430 is reduced to the Ni(I) oxidation state (By similarity).
Pathway
One-carbon metabolism; methyl-coenzyme M reduction; methane from methyl-coenzyme M: step 1/1.
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 150 | Ni (UniProtKB | ChEBI) of coenzyme F430 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: Q | ||||||
Binding site | 259 | coenzyme B (UniProtKB | ChEBI) | ||||
Sequence: K | ||||||
Binding site | 273 | coenzyme B (UniProtKB | ChEBI) | ||||
Sequence: R | ||||||
Binding site | 336 | coenzyme M (UniProtKB | ChEBI) | ||||
Sequence: Y | ||||||
Binding site | 447 | coenzyme M (UniProtKB | ChEBI) | ||||
Sequence: Y |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | cytoplasm | |
Molecular Function | coenzyme-B sulfoethylthiotransferase activity | |
Molecular Function | metal ion binding | |
Biological Process | methanogenesis |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameMethyl-coenzyme M reductase I subunit alpha
- EC number
- Short namesMCR I alpha
- Alternative names
Gene names
Organism names
- Strain
- Taxonomic lineageArchaea > Euryarchaeota > Methanomada group > Methanopyri > Methanopyrales > Methanopyraceae > Methanopyrus
Accessions
- Primary accessionQ49605
Proteomes
Subcellular Location
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000147454 | 1-553 | Methyl-coenzyme M reductase I subunit alpha | |||
Sequence: MSSAEEKLFMKALKEKFEESPEEKYTKFYIFGGWKQSERKKEFKEWADKIVEERGVPHYNPDIGVPLGQRKLMSYQVSGTDVFVEGDDLHFVNNAAMQQMWDDIRRTVIVGMDTAHRVLERRLGKEVTPETINEYMETLNHALPGGAVVQEHMVEIHPGLTWDCYAKIITGDLELADEIDDKFLIDIEKLFPEEQAEQLIKAIGNRTYQVCRMPTIVGHVCDGATMYRWAAMQIAMSFICAYKIAAGEAAVSDFAFASKHAEVINMGEMLPARRARGENEPGGVPFGVLADCVQTMRKYPDDPAKVALEVIAAGAMLYDQIWLGSYMSGGVGFTQYATAVYTDNILDDYVYYGLEYVEDKYGIAEAEPSMDVVKDVATEVTLYGLEQYERYPAAMETHFGGSQRAAVCAAAAGCSTAFATGHAQAGLNGWYLSQILHKEGHGRLGFYGYALQDQCGAANSLSVRSDEGLPLELRGPNYPNYAMNVGHLGEYAGIVQAAHAARGDAFCVHPVIKVAFADENLVFDFTEPRKEFAKGALREFEPAGERDLIVPAE |
Keywords
- PTM
Proteomic databases
Interaction
Subunit
MCR is a hexamer of two alpha, two beta, and two gamma chains, forming a dimer of heterotrimers.
Protein-protein interaction databases
Structure
Sequence
- Sequence statusComplete
- Length553
- Mass (Da)61,384
- Last updated2002-04-16 v2
- ChecksumF26582E0DCF2A434
Features
Showing features for sequence conflict.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Sequence conflict | 90 | in Ref. 1; AAB02003 | ||||
Sequence: H → T | ||||||
Sequence conflict | 342 | in Ref. 1; AAB02003 | ||||
Sequence: T → P | ||||||
Sequence conflict | 441 | in Ref. 1; AAB02003 | ||||
Sequence: H → Q |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
U57340 EMBL· GenBank· DDBJ | AAB02003.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
AE009439 EMBL· GenBank· DDBJ | AAM01870.1 EMBL· GenBank· DDBJ | Genomic DNA |