, encoding a Ca-regulated putative phytase, is evolutionarily conserved in and has potential as a biomarker.

infects patients with cystic fibrosis, burns, wounds and implants. Previously, our group showed that elevated Ca positively regulates the production of several virulence factors in , such as biofilm formation, production of pyocyanin and secreted proteases. We have identified a Ca-regulated β-propeller putative phytase, CarP, which is required for Ca tolerance, regulation of the intracellular Ca levels, and plays a role in Ca regulation of virulence.