A Multi-Serotype Approach Clarifies the Catabolite Control Protein A Regulon in the Major Human Pathogen Group A Streptococcus

Sci Rep. 2016 Sep 1:6:32442. doi: 10.1038/srep32442.

Abstract

Catabolite control protein A (CcpA) is a highly conserved, master regulator of carbon source utilization in gram-positive bacteria, but the CcpA regulon remains ill-defined. In this study we aimed to clarify the CcpA regulon by determining the impact of CcpA-inactivation on the virulence and transcriptome of three distinct serotypes of the major human pathogen Group A Streptococcus (GAS). CcpA-inactivation significantly decreased GAS virulence in a broad array of animal challenge models consistent with the idea that CcpA is critical to gram-positive bacterial pathogenesis. Via comparative transcriptomics, we established that the GAS CcpA core regulon is enriched for highly conserved CcpA binding motifs (i.e. cre sites). Conversely, strain-specific differences in the CcpA transcriptome seems to consist primarily of affected secondary networks. Refinement of cre site composition via analysis of the core regulon facilitated development of a modified cre consensus that shows promise for improved prediction of CcpA targets in other medically relevant gram-positive pathogens.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Female
  • Gene Expression Profiling
  • Gene Expression Regulation, Bacterial*
  • Humans
  • Mice
  • Nucleotide Motifs
  • Regulon*
  • Repressor Proteins / genetics*
  • Repressor Proteins / metabolism
  • Serogroup
  • Streptococcal Infections / microbiology
  • Streptococcal Infections / mortality
  • Streptococcal Infections / pathology
  • Streptococcus pyogenes / classification
  • Streptococcus pyogenes / genetics*
  • Streptococcus pyogenes / metabolism
  • Streptococcus pyogenes / pathogenicity*
  • Survival Analysis
  • Transcriptome*
  • Virulence

Substances

  • Bacterial Proteins
  • Repressor Proteins
  • catabolite control proteins, bacteria