Comparative analysis of two-component signal transduction systems of Bacillus cereus, Bacillus thuringiensis and Bacillus anthracis.
Members of the Bacillus cereus group are ubiquitously present in the environment and can adapt to a wide range of environmental fluctuations. In bacteria, these adaptive responses are generally mediated by two-component signal transduction systems (TCSs), which consist of a histidine kinase (HK) and its cognate response regulator (RR). With the use of in silico techniques, a complete set of HKs and RRs was recovered from eight completely sequenced B. cereus group genomes. By applying a bidirectional best-hits method combined with gene neighbourhood analysis, a footprint of these proteins was made. Around 40 HK-RR gene pairs were detected in each member of the B. cereus group. In addition, each member contained many HK and RR genes not encoded in pairs ("orphans"). Classification of HKs and RRs based on their enzymic domains together with the analysis of two neighbour-joining trees of these domains revealed putative interaction partners for most of the "orphans". Putative biological functions, including involvement in virulence and host-microbe interactions, were predicted for the B. cereus group HKs and RRs by comparing them with those of B. subtilis and other micro-organisms. Remarkably, B. anthracis appeared to lack specific HKs and RRs and was found to contain many truncated, putatively non-functional, HK and RR genes. It is hypothesized that specialization of B. anthracis as a pathogen could have reduced the range of environmental stimuli to which it is exposed. This may have rendered some of its TCSs obsolete, ultimately resulting in the deletion of some HK and RR genes.
de Been
Mark
M
Laboratory of Food Microbiology, Wageningen University and Research Centre, Wageningen, The Netherlands.|Centre for Molecular and Biomolecular Informatics (CMBI), Radboud University, PO Box 9101, 6500 HB Nijmegen, The Netherlands.|Wageningen Centre for Food Sciences (WCFS), Wageningen, The Netherlands.
Francke
Christof
C
Centre for Molecular and Biomolecular Informatics (CMBI), Radboud University, PO Box 9101, 6500 HB Nijmegen, The Netherlands.|Wageningen Centre for Food Sciences (WCFS), Wageningen, The Netherlands.
Moezelaar
Roy
R
Food Technology Centre, Wageningen University and Research Centre, Wageningen, The Netherlands.|Wageningen Centre for Food Sciences (WCFS), Wageningen, The Netherlands.
Abee
Tjakko
T
Laboratory of Food Microbiology, Wageningen University and Research Centre, Wageningen, The Netherlands.|Wageningen Centre for Food Sciences (WCFS), Wageningen, The Netherlands.
Siezen
Roland J
RJ
NIZO food research BV, Ede, The Netherlands.|Centre for Molecular and Biomolecular Informatics (CMBI), Radboud University, PO Box 9101, 6500 HB Nijmegen, The Netherlands.|Wageningen Centre for Food Sciences (WCFS), Wageningen, The Netherlands.
D000222:Adaptation, Physiological / Q000235:genetics; D001408:Bacillus anthracis / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D001409:Bacillus cereus / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D001413:Bacillus thuringiensis / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D001426:Bacterial Proteins / Q000235:genetics; D019295:Computational Biology; D005809:Genes, Regulator; D016680:Genome, Bacterial; D000071677:Histidine Kinase; D011494:Protein Kinases / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics*; D014774:Virulence / Q000235:genetics
D001426:Bacterial Proteins; D011494:Protein Kinases; D000071677:Histidine Kinase