Copyright © 1983, American Society for Microbiology Transductional Analysis of the Flagellar Genes in

Complementation in bacteriophage E79 tv-I-mediated transduction and the phenotypic properties of the flagellar genes in Pseudomonas aeruginosa PAO were investigated by using 195 flagellar mutants of this organism. A total of 15fla, 1 mot, and 2 che cistrons were identified. At least Sfla cistrons (flaV to flaZ) and one mot cistron resided in one region, and at least 10fla cistrons (flaA toflaJ) and two che cistrons (cheA and cheB) resided in another. The flaC mutants exhibited cistron-specific leakiness on motility agar plates. The flaE cistron may be the structural gene for the component protein of the flagellar filament. The cheA mutations, which resulted in pleiotropic phenotypes for flagellar formation, motility, and taxis, belonged to the same complementation group as the flaF mutations; that is, we inferred that cheA and flaF are synonymous. In Escherichia coli and Salmonella typhimul-riium, the genes for related functions in many cases are arranged contiguously on the chromo-some, and this arrangement has been shown t