Expression control of ssaJ and ssaK of SPI2 in Salmonella typhimurium

Salmonella typhimurium에서 SPI2의 ssaK와 ssaJ의 발현조절

  • 최혁진 (고려대학교 이과대학 생물학과) ;
  • 엄준호 (고려대학교 이과대학 생물학과) ;
  • 이인수 (한남대학교 이과대학 미생물학과) ;
  • 박경량 (한남대학교 이과대학 미생물학과) ;
  • 박용근 (고려대학교 생명공학원)
  • Received : 1998.04.07
  • Accepted : 1998.06.10
  • Published : 1998.09.01

Abstract

Salmonella Pathgenicity Island 2 plays an important role in Salmonella pathogenicity, especially invasion into host cell. We have investigated the effect of various environmental factors, such as oxygen level, osmolarity, pH, carbon starvation and glycerol addition on the expression of SPI2. For this research, we constructed the reporter plasmids, in which the promoter-less lac operons are fused with the regulatory regions (including promoter) of ssaJ and ssaK, major genes in SPI2. The study using the reporters showed that low oxygen, low osmolarity, or weak alkali conditions increased the expression levels of ssaJ and ssaK and when these three conditions exist simultaneously, the expression levels of ssaJ and ssaK are the highest. However carbon starvation and glycerol addition did not affect the expression of ssaJ and ssaK. These environmental effects on the expression levels of ssaJ and ssaK are the same in three Salmonella typhimurium wild types, LT2, UK1, and SL1344. In addition, we confirmed that the mutation in hilA, a regulatory gene encoding a transcriptional activator of SPI1, had no effect on the expression of ssaJ and ssaK. Thus, these results strongly suggest that the expressions of SPI2 and SPI1 are regulated by different control systems.

Keywords

Invasion;pathogenicity;Salmonella;SPI2

Acknowledgement

Supported by : 보건복지부