Protein kinase that recognizes the calcium spiking induced by Nod factors and translates this signal to components controlling nodulation and mycorrhizal infection responses. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Activated by calcium. Autophosphorylation may play an important role in the regulation of the kinase activity (By similarity). Autophosphorylation. Belongs to the protein kinase superfamily. CAMK Ser/Thr protein kinase family. CaMK subfamily.