Metabolic Activation of CsgD in the Regulation of Salmonella Biofilms

Microorganisms

TaseenS. Desin¹  Yejun Wang²  KeithD. MacKenzie³  NancyJ. Herman⁴  LandonL. Waldner⁴  AkosiereremS. Sokaribo⁴  ElizabethG. Hansen⁴  AaronP. White⁴  Madeline McCarthy⁴  George Mutwiri Jr.⁴  DakodaJ. Herman⁴ 

[1] Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon S7N 5E5, Canada;Department of Cell Biology and Genetics, School of Basic Medicine, Shenzhen University Health Science, Shenzhen 518060, China;Institute for Microbial Systems and Society, Faculty of Science, University of Regina, Regina S4S 0A2, Canada;Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, Saskatoon S7N 5E3, Canada;

关键词: biofilm;    Salmonella;    CsgD;    curli;    cellulose;    CpxR;   

DOI  :  10.3390/microorganisms8070964

来源: DOAJ

【 摘 要 】

Among human food-borne pathogens, gastroenteritis-causing Salmonella strains have the most real-world impact. Like all pathogens, their success relies on efficient transmission. Biofilm formation, a specialized physiology characterized by multicellular aggregation and persistence, is proposed to play an important role in the Salmonella transmission cycle. In this manuscript, we used luciferase reporters to examine the expression of csgD, which encodes the master biofilm regulator. We observed that the CsgD-regulated biofilm system responds differently to regulatory inputs once it is activated. Notably, the CsgD system became unresponsive to repression by Cpx and H-NS in high osmolarity conditions and less responsive to the addition of amino acids. Temperature-mediated regulation of csgD on agar was altered by intracellular levels of RpoS and cyclic-di-GMP. In contrast, the addition of glucose repressed CsgD biofilms seemingly independent of other signals. Understanding the fine-tuned regulation of csgD can help us to piece together how regulation occurs in natural environments, knowing that all Salmonella strains face strong selection pressures both within and outside their hosts. Ultimately, we can use this information to better control Salmonella and develop strategies to break the transmission cycle.

【 授权许可】

Unknown