GCA_000018585.1 P9211_00741 definition HIT (Histidine triad) family protein GCA_000018585.1 P9211_02961 definition two-component sensor histidine kinase GCA_000018585.1 P9211_11111 definition two-component sensor histidine kinase GCA_000018585.1 P9211_13951 definition two-component sensor histidine kinase GCA_000018585.1 P9211_15011 definition Signal transduction histidine kinase