A mutant of Pseudomonas aeruginosa that lacks c-type cytochromes has a functional cyanide-insensitive oxidase.
Using transposon mutagenesis and screening for the loss of the ability to oxidise the artificial electron donor N,N,N',N'-tetramethyl-p-phenylenediamine, we have isolated a mutant of Pseudomonas aeruginosa that lacks all c-type cytochromes. This mutant is unable to grow anaerobically with nitrate as a terminal electron acceptor. Analysis of its respiratory function indicates that the mutant has lost its cytochrome c oxidase-terminated respiratory pathway but the cyanide-insensitive oxidase-terminated branch remains functional. Complementation of the mutant by in vivo cloning led to recovery of the wild-type characteristics. These data are consistent with the idea that the cyanide-insensitive respiratory pathway does not contain haem c and that the pathway's terminal oxidase is a quinol oxidase.
Ray
A
A
Department of Biology, Imperial College of Science, Technology and Medicine, London, UK.
Williams
H D
HD
D003576:Electron Transport Complex IV / Q000378:metabolism*; D009154:Mutation; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism*; D011550:Pseudomonas aeruginosa / Q000201:enzymology* / Q000235:genetics; D013045:Species Specificity; D013772:Tetramethylphenylenediamine / Q000378:metabolism*
D010088:Oxidoreductases; C020094:duroquinol oxidase; D003576:Electron Transport Complex IV; D013772:Tetramethylphenylenediamine