Disruption of Outer Membrane Biogenesis Leads to Attenuation of Yersinia pseudotuberculosis

The goal of this study is to identify the effect of deletion of some genes encoding biogenesis of outer membrane protein complex components on the virulence of Yersinia pseudotuberculosis mutants. Y. pseudotuberculosis surA, degP, bamB, and ompH mutants were generated by mutagenesis using suicide vectors. The constructed mutants were characterized by growth rate, sensitivity to antibiotics, bile salts, and sodium dodecyl sulfate, as well as to the bactericidal action of normal human serum. The total composition of the outer membrane proteins of the knockout mutants was determined by SDS-PAGE. The virulence of ΔsurA, ΔdegP, ΔbamB, and ΔompH was studied after subcutaneous, intraperitoneal, or oral administration of mice. It was found that BamB, OmpH, and SurA proteins were necessary for maintaining the integrity of the Y. pseudotuberculosis cell membrane and that SurA and BamB proteins are important for resistance to the bactericidal action of serum complement, and a high degree of attenuation of Y. pseudotuberculosis strains with deleted surA, degP, and bamB genes for outbred mice was revealed. The surA, degP, and bamB genes can be used as potential molecular targets for construction of Y. pseudotuberculosis vaccine strains.