Member of the two-component regulatory system WalK/WalR that regulates genes involved in cell wall metabolism, virulence regulation, biofilm production, oxidative stress resistance and antibiotic resistance via direct or indirect regulation of autolysins. Functions as a sensor protein kinase which is autophosphorylated at a histidine residue in the dimerization domain and transfers its phosphate group to the conserved aspartic acid residue in the regulatory domain of WalR. In turn, WalR binds to the upstream promoter regions of the target genes to positively and negatively regulate their expression.

> 85% as determined by SDS-PAGE.