NPTX2 and infection: Due to the requirement of the aerobic cytochrome bo3 during single-species P. mirabilis CAUTI, it is noteworthy that the respiratory nitrate reductase system (narGHJI), the narXL two-component sensor kinase, the narP response regulator, the narK nitrite extrusion protein, the nirB nitrite reductase, and the flavohemoprotein hmp were all identified as candidate P. mirabilis fitness factors during coinfection but not single-species infection.