Genetic characterization of mutations which affect catabolite-sensitive operons in Escherichia coli, including deletions of the gene for adenyl cyclase.

Sixty-two spontaneous mutations have been characterized which reduce the level of expression of catabolite-sensitive operons. These mutations appear to affect either the crp (catabolite gene activator protein) or cya (adenyl cyclase) loci. No new loci have been discovered. Deletions of the cya gene do not remove an essential function. phi80 transducing phage for the cya gene have been used to do recombination and complementation studies on cya mutants.