Q7MSJ8 · MCCA_WOLSU
- ProteinDissimilatory sulfite reductase MccA
- GenemccA
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids702 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Respiratory sulfite reductase that catalyzes the reduction of sulfite to sulfide in a single step, consuming six electrons in the process (PubMed:22040142, PubMed:25642962).
Required for sulfite respiration under anaerobic growth conditions (PubMed:22040142).
Has only marginal activity with nitrite
Required for sulfite respiration under anaerobic growth conditions (PubMed:22040142).
Has only marginal activity with nitrite
Miscellaneous
The eighth heme binding site has an unusual CXXXXXCH motif.
Catalytic activity
- [protein]-disulfide + 2 A + 3 H2O + hydrogen sulfide = [protein]-dithiol + 2 AH2 + H+ + sulfite
RHEA-COMP:10593 + 2 CHEBI:13193 + 3 CHEBI:15377 + CHEBI:29919 = RHEA-COMP:10594 CHEBI:29950 Position: C1CHEBI:29950 Position: C2+ 2 CHEBI:17499 + CHEBI:15378 + CHEBI:17359
Cofactor
Protein has several cofactor binding sites:
Note: Exposure to oxygen reduces copper binding and leads to the formation of a disulfide bond between the two Cys residues that bind the copper ion.
Note: Binds 8 heme c groups covalently per monomer.
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
44 μM | sulfite |
Vmax | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|
151 μmol/min/mg | with sulfite as substrate |
Pathway
Sulfur metabolism; sulfite reduction.
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 155 | heme c 1 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 158 | heme c 1 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 159 | Fe (UniProtKB | ChEBI) of heme c 1 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 171 | Fe (UniProtKB | ChEBI) of heme c 4 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 220 | substrate | ||||
Sequence: K | ||||||
Binding site | 297 | substrate | ||||
Sequence: Y | ||||||
Binding site | 314 | heme c 2 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 317 | heme c 2 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 318 | Fe (UniProtKB | ChEBI) of heme c 2 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 351 | heme c 3 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 354 | heme c 3 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 355 | Fe (UniProtKB | ChEBI) of heme c 3 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 360 | Fe (UniProtKB | ChEBI) of heme c 1 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 372 | heme c 4 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 375 | heme c 4 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 376 | Fe (UniProtKB | ChEBI) of heme c 4 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 378 | substrate | ||||
Sequence: R | ||||||
Binding site | 411 | Cu+ (UniProtKB | ChEBI) | ||||
Sequence: C | ||||||
Binding site | 423 | Fe (UniProtKB | ChEBI) of heme c 6 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 430 | heme c 5 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 433 | heme c 5 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 434 | Fe (UniProtKB | ChEBI) of heme c 5 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 437 | Fe (UniProtKB | ChEBI) of heme c 3 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 474 | heme c 6 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 477 | heme c 6 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 478 | Fe (UniProtKB | ChEBI) of heme c 6 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 491 | Fe (UniProtKB | ChEBI) of heme c 8 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 496 | heme c 7 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 499 | heme c 7 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 500 | Fe (UniProtKB | ChEBI) of heme c 7 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 507 | Cu+ (UniProtKB | ChEBI) | ||||
Sequence: C | ||||||
Binding site | 528 | Fe (UniProtKB | ChEBI) of heme c 5 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 574 | heme c 8 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 590 | heme c 8 (UniProtKB | ChEBI); covalent | ||||
Sequence: C | ||||||
Binding site | 591 | Fe (UniProtKB | ChEBI) of heme c 8 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H | ||||||
Binding site | 675 | Fe (UniProtKB | ChEBI) of heme c 7 (UniProtKB | ChEBI); axial binding residue | ||||
Sequence: H |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | periplasmic space | |
Molecular Function | cuprous ion binding | |
Molecular Function | heme binding | |
Molecular Function | identical protein binding | |
Molecular Function | oxidoreductase activity, acting on a sulfur group of donors | |
Molecular Function | sulfite reductase activity | |
Biological Process | anaerobic respiration | |
Biological Process | hydrogen sulfide biosynthetic process | |
Biological Process | protein homotrimerization |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameDissimilatory sulfite reductase MccA
- EC number
Gene names
Organism names
- Strain
- Taxonomic lineageBacteria > Campylobacterota > Epsilonproteobacteria > Campylobacterales > Helicobacteraceae > Wolinella
Accessions
- Primary accessionQ7MSJ8
Proteomes
Subcellular Location
Phenotypes & Variants
Disruption phenotype
Loss of growth based on sulfite respiration.
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 574 | Impairs protein stability and abolishes sulfite reductase activity; when associated with C-587. | ||||
Sequence: C → A | ||||||
Mutagenesis | 587 | Impairs protein stability and abolishes sulfite reductase activity; when associated with A-574. | ||||
Sequence: A → C | ||||||
Mutagenesis | 587 | No effect on protein stability and sulfite reductase activity. | ||||
Sequence: A → S | ||||||
Mutagenesis | 590 | Impairs protein stability. | ||||
Sequence: C → A or S | ||||||
Mutagenesis | 591 | Impairs protein stability. | ||||
Sequence: H → A |
PTM/Processing
Features
Showing features for signal, chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Signal | 1-39 | |||||
Sequence: MLSGWSVLKGGNMKYWDKALLSLFMCVSTLSIAATHAVA | ||||||
Chain | PRO_0000432940 | 40-702 | Dissimilatory sulfite reductase MccA | |||
Sequence: MEGMQMTKEAREIIAHPKGTKESRGVISLQDYIVEEQAMYDWLFKNHPIFTKYGGKTVGKLVVKDRGEEWIEEGRGNDFSKASKRSGGEGFSSMMYRVARNSTLQYPNKFIGPEKCGECHPAQYETWSRSRHATTIRFPGEHPEVNNKLNDPVFDKDTASILPQGITPDVVYCTVGHIRTKFGFFDAWLLRGTYHVEGGLLKNGTGQIVAGGNQWQRTWALNLSPEVAKKIKKWVPDFPVTLEEYGDNGGYVRGLASYAAKYKKSMSFQASTSYCEVCHPWKFDFKNESEFYAALGNAKELQKHTISKGVSCEECHGAGGHLEGGSGLLISNCERCHQRFSYSPDLMRNNPLNAGKPDLALSSKFKSMGPGCGSEGSQTYFTAHYEKGMRCATCHDPHDVTGNVTGEKGIKGVSYNSEQGYLSSLYSKPKLKKECTDCHKEQAYIQSKADTHSKNSCASCHMPFMMSCENFYAIQFQDQAGFDTQRRAHIWKIDVDPARKSLVAGSTSKDPRDGKDWHFERNEEGRNFVDLMWACARTTWADKDQAEAKGCHSPVVSELKETLHFKDQKQVYNEVMGWQTPVKDKFTQVKVGIQGLYSLLEVKKLAPSDKTRVYELIEKAQDTVDLIEKDGSWGMHGFKYTKQRLDAAVEYINEAQRIMKKSL |
Expression
Induction
Repressed by fumarate and nitrate. Up-regulated by sulfite, but only in the absence of fumarate and nitrate (at protein level).
Interaction
Subunit
Homotrimer.
Binary interactions
Type | Entry 1 | Entry 2 | Number of experiments | Intact | |
---|---|---|---|---|---|
BINARY | Q7MSJ8 | mccA Q7MSJ8 | 2 | EBI-16140995, EBI-16140995 |
Protein-protein interaction databases
Structure
Sequence
- Sequence statusComplete
- Sequence processingThe displayed sequence is further processed into a mature form.
- Length702
- Mass (Da)78,939
- Last updated2003-12-15 v1
- Checksum7F03B02298162E28
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
BX571658 EMBL· GenBank· DDBJ | CAE09526.1 EMBL· GenBank· DDBJ | Genomic DNA |