Effect of oxygen limitation on the formation of the electron transport system of the phytopathogenic fluorescent bacterium Pseudomonas cichorii.

The composition of the membrane-bound electron transport system of the phytopathogenic bacterium Pseudomonas cichorii underwent modification in response to oxygen supply. Growth adaptation to low oxygen concentrations was characterized by repression of cytochromes involved in ubiquinol-cyt. c oxidoreductase and cyt. c oxidase activities. By contrast, cyto. o, i.e., the alternative cyanide-insensitive oxidase of P. cichorii, was unaffected by low oxygen tension. No a-type cytochromes could be detected at any stage of growth.