Member of the two-component regulatory system PhoP/PhoR involved in the alkaline phosphatase genes regulation. PhoR may function as a membrane-associated protein kinase that phosphorylates PhoP in response to environmental signals. ATP + protein L-histidine = ADP + protein N-phospho-L-histidine. Oligomerizes, probably forms homodimers. Interacts with FloA, colocalizes with FloA-only membrane rafts. Oligomerization is assisted by FloA (PubMed:25909364). Another study shows only minor colocalization with FloA or FloT (PubMed:27362352).