Proteomic analysis of <i>Pseudomonas chlororaphis</i> subsp. <i>aurantiacа</i> strains capable of phenasine compounds overproduction

Abstract

Proteomic analysis is a highly effective method for bacteria identification and the elucidation of protein's content in prokaryotic cells at different growth conditions. To our knowledge this approach is hardly ever used for characterization of producers of biologically active substances. The understanding of the changes in protein profile in mutant strains capable of biologically active substances overproduction helps to recognize the biochemical and molecular basis of metabolic changes which lead to overproduction. So that, proteomic analysis could be especially useful for optimization the producer's creation techniques.The purpose of current research was to carry out proteomic profiling of bacteria P. chlororaphis subsp. aurantiaca mutant strains capable of overproduction of phenazine antibiotics. Microbiological and biochemical methods were used for these aims.In current research a proteomic analysis of strains of P. chlororaphis subsp. aurantiaca producing phenazines was carried out. An early (during log-phase) onset of expression of individual genes of phz-operon which codes enzymes for phenazines synthesis was demonstrated. It was also found that the wild type strain has the highest level of PhzO protein. The gene encoding this protein is located outside the phz-operon. We weren't able to establish the correlation among PhzO protein content and concentration of the derivatives for which appearance PhzO is responsible. A general tendency of producer strains towards the accumulation of enzymes and proteins of the antioxidant defense system was revealed. Producer strains also demonstrate a significant increase in the concentration of proteins involved in DNA repair as well as chaperones involved in the native protein conformation maintenance.