UniProt functional annotation for Q8P9V9



	UniProt functional annotation for Q8P9V9

UniProt code: Q8P9V9.

Organism: Xanthomonas campestris pv. campestris (strain ATCC 33913 / DSM 3586 / NCPPB 528 / LMG 568 / P 25).

Taxonomy: Bacteria; Proteobacteria; Gammaproteobacteria; Xanthomonadales; Xanthomonadaceae; Xanthomonas.

Function: Thiol-specific peroxidase that catalyzes the reduction of hydrogen peroxide and organic hydroperoxides to water and alcohols, respectively. Plays a role in cell protection against oxidative stress by detoxifying peroxides and as sensor of hydrogen peroxide-mediated signaling events. {ECO:0000269|PubMed:19477183}.

Catalytic activity: Reaction=[thioredoxin]-dithiol + a hydroperoxide = [thioredoxin]- disulfide + an alcohol + H2O; Xref=Rhea:RHEA:62620, Rhea:RHEA- COMP:10698, Rhea:RHEA-COMP:10700, ChEBI:CHEBI:15377, ChEBI:CHEBI:29950, ChEBI:CHEBI:30879, ChEBI:CHEBI:35924, ChEBI:CHEBI:50058; EC=1.11.1.24; Evidence={ECO:0000269|PubMed:19477183, ECO:0000269|PubMed:27594682};

Biophysicochemical properties: Kinetic parameters: KM=786 uM for H(2)O(2) {ECO:0000269|PubMed:27594682}; KM=1840 uM for cumene hydroperoxide {ECO:0000269|PubMed:27594682}; KM=293 uM for TrxA (using H(2)O(2) as substrate) {ECO:0000269|PubMed:27594682}; KM=414 uM for TrxA (using cumene hydroperoxide as substrate) {ECO:0000269|PubMed:27594682};

Subunit: Monomer. {ECO:0000269|PubMed:19477183}.

Miscellaneous: The active site is a conserved redox-active cysteine residue, the peroxidatic cysteine (C(P)), which makes the nucleophilic attack on the peroxide substrate. The peroxide oxidizes the C(P)-SH to cysteine sulfenic acid (C(P)-SOH), which then reacts with another cysteine residue, the resolving cysteine (C(R)), to form a disulfide bridge. The disulfide is subsequently reduced by an appropriate electron donor to complete the catalytic cycle. In this atypical 2-Cys peroxiredoxin, C(R) is present in the same subunit to form an intramolecular disulfide. The disulfide is subsequently reduced by thioredoxin. {ECO:0000305|PubMed:19477183}.

Similarity: Belongs to the peroxiredoxin family. BCP/PrxQ subfamily. {ECO:0000305}.

Annotations taken from UniProtKB at the EBI.


Organism:		Xanthomonas campestris pv. campestris (strain ATCC 33913 / DSM 3586 / NCPPB 528 / LMG 568 / P 25).
Taxonomy:		Bacteria; Proteobacteria; Gammaproteobacteria; Xanthomonadales; Xanthomonadaceae; Xanthomonas.



Function:		Thiol-specific peroxidase that catalyzes the reduction of hydrogen peroxide and organic hydroperoxides to water and alcohols, respectively. Plays a role in cell protection against oxidative stress by detoxifying peroxides and as sensor of hydrogen peroxide-mediated signaling events. {ECO:0000269\|PubMed:19477183}.


Catalytic activity:		Reaction=[thioredoxin]-dithiol + a hydroperoxide = [thioredoxin]- disulfide + an alcohol + H2O; Xref=Rhea:RHEA:62620, Rhea:RHEA- COMP:10698, Rhea:RHEA-COMP:10700, ChEBI:CHEBI:15377, ChEBI:CHEBI:29950, ChEBI:CHEBI:30879, ChEBI:CHEBI:35924, ChEBI:CHEBI:50058; EC=1.11.1.24; Evidence={ECO:0000269\|PubMed:19477183, ECO:0000269\|PubMed:27594682};
Biophysicochemical properties:		Kinetic parameters: KM=786 uM for H(2)O(2) {ECO:0000269\|PubMed:27594682}; KM=1840 uM for cumene hydroperoxide {ECO:0000269\|PubMed:27594682}; KM=293 uM for TrxA (using H(2)O(2) as substrate) {ECO:0000269\|PubMed:27594682}; KM=414 uM for TrxA (using cumene hydroperoxide as substrate) {ECO:0000269\|PubMed:27594682};
Subunit:		Monomer. {ECO:0000269\|PubMed:19477183}.
Miscellaneous:		The active site is a conserved redox-active cysteine residue, the peroxidatic cysteine (C(P)), which makes the nucleophilic attack on the peroxide substrate. The peroxide oxidizes the C(P)-SH to cysteine sulfenic acid (C(P)-SOH), which then reacts with another cysteine residue, the resolving cysteine (C(R)), to form a disulfide bridge. The disulfide is subsequently reduced by an appropriate electron donor to complete the catalytic cycle. In this atypical 2-Cys peroxiredoxin, C(R) is present in the same subunit to form an intramolecular disulfide. The disulfide is subsequently reduced by thioredoxin. {ECO:0000305\|PubMed:19477183}.
Similarity:		Belongs to the peroxiredoxin family. BCP/PrxQ subfamily. {ECO:0000305}.