Dissecting the cyclic di-guanylate monophosphate signalling network regulating motility in Salmonella enterica serovar Typhimurium

Environ Microbiol. 2015 Apr;17(4):1310-20. doi: 10.1111/1462-2920.12580. Epub 2015 Jan 30.

Abstract

Flagella-mediated swimming and swarming motility in Salmonella enterica serovar Typhimurium is intercalated with the cyclic di-guanylate monophosphate (c-di-GMP) signalling network. In this study, we identified the GGDEF domain proteins STM2672, STM4551 and STM1987 as key di-guanylate cyclases involved in regulation of motility in a ΔyhjH phosphodiesterase gene deletion mutant with elevated c-di-GMP levels inhibiting motility. Surprisingly, these di-guanylate cyclases distinctively inhibited motility through the c-di-GMP receptors YcgR and the cellulose synthase BcsA, whereby STM2672 corresponded to YcgR, STM1987 to BcsA and STM4551 to both receptors. Although downregulation of motility is believed to prepare the bacterial cells for surface adhesion and biofilm formation, the major biofilm regulator CsgD of S. sv. Typhimurium was not involved in the regulation of swimming or swarming motility. Together with previously identified c-di-GMP networks regulating flagella-related phenotypes, flagella biosynthesis is a major target of c-di-GMP signalling in S. sv. Typhimurium.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Adhesion / genetics
  • Biofilms / growth & development*
  • Carrier Proteins / metabolism
  • Cyclic GMP / analogs & derivatives*
  • Cyclic GMP / genetics
  • Cyclic GMP / metabolism
  • Flagella / genetics
  • Flagella / physiology*
  • Gene Deletion
  • Gene Expression Regulation, Bacterial
  • Glucosyltransferases / genetics
  • Glucosyltransferases / metabolism
  • Phosphoric Diester Hydrolases / genetics
  • Protein Structure, Tertiary
  • Salmonella typhimurium / genetics
  • Salmonella typhimurium / physiology*
  • Trans-Activators / biosynthesis

Substances

  • Carrier Proteins
  • Trans-Activators
  • bis(3',5')-cyclic diguanylic acid
  • Glucosyltransferases
  • cellulose synthase
  • Phosphoric Diester Hydrolases
  • Cyclic GMP