UniProt functional annotation for P0AA89

UniProt code: P0AA89.

Organism: Escherichia coli (strain K12).
Taxonomy: Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacterales; Enterobacteriaceae; Escherichia.
 
Function: Globin-coupled heme-based oxygen sensor protein displaying diguanylate cyclase (DGC) activity in response to oxygen availability. Thus, catalyzes the synthesis of cyclic diguanylate (c-di-GMP) via the condensation of 2 GTP molecules. Is involved in the modulation of intracellular c-di-GMP levels, in association with DosP which catalyzes the degradation of c-di-GMP (PDE activity). Cyclic-di-GMP is a second messenger which controls cell surface-associated traits in bacteria. DosC regulates biofilm formation through the oxygen-dependent activation of the csgBAC operon, which encodes curli structural subunits, while not affecting the expression of the regulatory operon csgDEFG. DosC, but not the other DGCs in E.coli, also promotes the production of the exopolysaccharide poly-N-acetylglucosamine (PNAG) through up-regulation of the expression of the PNAG biosynthetic pgaABCD operon, independently of CsrA.
 
Function: Overexpression leads to an increased level of c-di-GMP, which leads to changes in the cell surface, to abnormal cell division, increased biofilm formation and decreased swimming (the latter 2 in strain W3110). In a strain able to produce cellulose (strain TOB1, a fecal isolate) overexpression leads to an increase in cellulose production.
 
Catalytic activity: Reaction=2 GTP = cyclic di-3',5'-guanylate + 2 diphosphate; Xref=Rhea:RHEA:24898, ChEBI:CHEBI:33019, ChEBI:CHEBI:37565, ChEBI:CHEBI:58805; EC=2.7.7.65; Evidence={ECO:0000269|PubMed:19764732, ECO:0000269|PubMed:21067162};
Cofactor: Name=heme; Xref=ChEBI:CHEBI:30413; Note=Binds 1 heme group per subunit. The Fe(2+) state binds O(2) and CO while the Fe(3+) state can bind CN(-) and imidazole.;
Cofactor: Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000250}; Note=Binds 1 Mg(2+) ion per subunit. {ECO:0000250};
Activity regulation: Activity depends on O(2)-binding and heme redox state: the Fe(III), Fe(II)-O(2), and Fe(II)-CO complexes of DosC are active forms, whereas Fe(II) and Fe(II)-NO complexes are inactive forms. {ECO:0000269|PubMed:21067162}.
Biophysicochemical properties: Kinetic parameters: Note=The Fe(III), Fe(II)-O(2), and Fe(II)-CO complexes of DosC display DGC activity with turnover numbers of 0.066, 0.022, and 0.022 min(-1), respectively. The DGC reaction catalyzed by DosC is the rate-determining step for c-di-GMP homeostasis. Binds O(2), CO, cyanide and imidazole with a dissociation constant of 14 uM, 0.095 uM, 4.7 uM and 0.055 uM, respectively. {ECO:0000269|PubMed:21067162}; Redox potential: E(0) is -17 mV.;
Pathway: Purine metabolism; 3',5'-cyclic di-GMP biosynthesis.
Subunit: Forms a complex with DosP.
Induction: By RpoS in the late exponential growth phase and upon entry into stationary phase. Expression is higher at 28 than 37 degrees Celsius. In rich medium DosC and DgcM are the major RpoS-dependent GGDEF-domain containing proteins in the cell, whereas in minimal medium it is the major RpoS-dependent GGDEF-domain containing protein. Highly expressed on solid medium. A member of the dosCP operon. {ECO:0000269|PubMed:19332833, ECO:0000269|PubMed:20553324}.
Domain: Is composed of an N-terminal sensory globin-fold domain that binds heme and oxygen, and a C-terminal GGDEF diguanylate cyclase domain. {ECO:0000269|PubMed:21067162}.
Disruption phenotype: Disruption results in a 2.5-fold reduction in surface adhesion, a 3.5-fold reduction in biofilm formation, a large reduction in curli production, a drastic decrease in csgB expression (400-fold reduction in aerobic growth) and in an approximately 3.5-fold reduction in pgaA transcript levels in comparison with wild-type. Disruption partially suppresses the reduced motility of a pdeH disruption; concomitant disruption of dosC, dgcE, dgcQ and dgcN completely restores motility, suggesting these 4 genes, together with the c-di-GMP phosphodiesterase PdeH, form a network that regulates cell motility by altering levels of c-di-GMP. {ECO:0000269|PubMed:20303158, ECO:0000269|PubMed:20553324, ECO:0000269|PubMed:20576684}.
Sequence caution: Sequence=BAA15155.2; Type=Erroneous initiation; Note=Truncated N-terminus.; Evidence={ECO:0000305};

Annotations taken from UniProtKB at the EBI.