Identification of the polyamine induced proteins in Escherichia coli

The polyamine (PA)-induced proteins were identified by SDS-PAGE, and by two dimensional gel analysis in Escherichia coli strains. A large number of th e PA-induced proteins were acidic. The molecular weights of the most highly induced proteins were 40 and 82 kDa proteins in the wild type and PA-auxot rophic mutant, respectively. Although a part of the PA-induced proteins wer e induced both in the wild type and PA auxotrophic mutant, most of them see m to be induced either in the wild type or mutant. These features may provi de a foundation for evaluating the role of the PA-induced proteins relative to the physiology and environmental stress of Escherichia coli.