KinB_sensor is the N-terminal sensor domain of histidine kinase from Pseudomonas species. The domain is the extracellular sensing domain, and is four helical bundle [1,2]. It recognises inorganic phosphate Matilla et. al., FEMS Microbiology Reviews, fuab043, 45, 2021, 1. https://doi.org/10.1093/femsre/fuab043).

1: Histidine protein kinases: key signal transducers outside the animal kingdom. Wolanin PM, Thomason PA, Stock JB; Genome Biol. 2002;3:REVIEWS3013. PMID:12372152

2: Identification of the histidine protein kinase KinB in Pseudomonas aeruginosa and its phosphorylation of the alginate regulator algB. Ma S, Wozniak DJ, Ohman DE; J Biol Chem. 1997;2:17952-60. PMID:9218420