Pathways & interactions
Lipopolysaccharide core heptose(I) kinase rfaP (IPR017172)
Short name: Lsacc_core_hep_kinase_RfaP
Overlapping homologous superfamilies
- Protein kinase-like domain superfamily (IPR011009)
Protein phosphorylation, which plays a key role in most cellular activities, is a reversible process mediated by protein kinases and phosphoprotein phosphatases. Protein kinases catalyse the transfer of the gamma phosphate from nucleotide triphosphates (often ATP) to one or more amino acid residues in a protein substrate side chain, resulting in a conformational change affecting protein function. Phosphoprotein phosphatases catalyse the reverse process. Protein kinases fall into three broad classes, characterised with respect to substrate specificity [PMID: 3291115]:
- Serine/threonine-protein kinases
- Tyrosine-protein kinases
- Dual specificity protein kinases (e.g. MEK - phosphorylates both Thr and Tyr on target proteins)
Protein kinase function is evolutionarily conserved from Escherichia coli to human [PMID: 12471243]. Protein kinases play a role in a multitude of cellular processes, including division, proliferation, apoptosis, and differentiation [PMID: 12368087]. Phosphorylation usually results in a functional change of the target protein by changing enzyme activity, cellular location, or association with other proteins. The catalytic subunits of protein kinases are highly conserved, and several structures have been solved [PMID: 15078142], leading to large screens to develop kinase-specific inhibitors for the treatments of a number of diseases [PMID: 15320712].
This entry represents the lipopolysaccharide core heptose(I) kinase rfaP, which is required for the addition of phosphate to O-4 of the first heptose residue of the lipopolysaccharide (LPS) inner core region. It has previously been shown that RfaP is necessary for resistance to hydrophobic and polycationic antimicrobials in Escherichia coli, and that it is required for virulence in invasive strains of S. enterica [PMID: 11069912].
- PIRSF037318 (RfaP)