Expression of multiple cbb 3 cytochrome c oxidase isoforms by combinations of multiple isosubunits in Pseudomonas aeruginosa

Significance The cbb 3 cytochrome c oxidase has high affinity for oxygen and is typically used for respiration in many pathogenic bacteria in hypoxic environments. Here we show that the opportunistic human pathogen Pseudomonas aeruginosa has a capability to produce 16 different cbb 3 isoforms by combinations of multiple isosubunits. Utilization of multiple isoforms with different properties contributes to the robustness of the bacterium under hypoxic growth conditions and might have practical implications for resistance to antibiotics and formations of biofilms and persister cells. Our findings indicate that the mechanism for the production of the isoforms could be possible therapeutic targets for treating chronic P. aeruginosa infection.