FP6 priority

1.1.1   Genomics and Biotechnology for Health

1.1.1.1

Title of the proposal

A connection between stress, differentiation and pathogenicity of bacteria

Institute

Slovak Academy of Sciences, Institute of Molecular Biology
Dubravska 21, 84251 Bratislava, Slovak Republic

Contact

Research subject for a potential FP6 project

Heterogeneity of sigma factors of RNA polymerase plays a key role in response of bacteria to various stress conditions, as well as in a process of cell differentiation. In our previous studies, we have shown a role of sigma factors in morphological differentiation of Streptomyces. Moreover, we have identified and characterised sigma factor SigH with a dual role in stress-response and diffe-rentiation. For some pathogenic bacteria the stress-response directly affects virulence by influencing key host-pathogen interactions, and stress-response sigma factors have been shown to be involved in the process of pathogenicity. The principal aim of the project is to identify regulon of Streptomyces dual stress-response sigma factor SigH and regulons of other stress-response sigma factors potentialy involved in the pathogenicity of several pathogenic bacteria by applying our previously established efficient method for identification of promoters recognized by a particular RNA polymerase sigma factor. At present, we are optimising the method for identification of regulons for Salmonella typhimurium RpoE, Staphylococcus aureus SigB and Mycobacterium tuberculosis SigF sigma factors that have been shown to be involved in pathogenicity of the corresponding bacterium. The identified genes will be characterised to determine their role in virulence, the interaction with the host , and the defence against stress. We would greatly appreciate to involve also other possible sigma factor candidates likely involved in pathogenicity of other bacteria in the project of identification of their regulons and role of the identified genes in pathogenicity as a part of a project for the 6FP.

Recent international cooperation of the research team

1. Prof. Mark Roberts, Department of Veterinary Pathology, Glasgow University Veterinary School, Glasgow, U.K. – role of stress-response sigma faktor RpoE in pathogenicity of Salmonella typhimurium.
2. Dr. Markus Bischoff, Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland,- role of stress-response sigma factor SigB in pathogenicity of Staphylococcus aureus.
3. Prof. Patrick J. Brennan, Department of Microbiology, Colorado State University, Fort Collins, USA – role of stress-response sigma factor SigF in pathogenicity of Mycobacterium tuberculosis.

Proposer´s relevant publications related to the research subject

1. Novakova, R., Sevcikova, B., Kormanec, J. (1998) A method for the identification of promoters recognized by RNA polymerase containing a particular sigma factor: Cloning of a developmentally regulated promoter and corresponding gene directed by the Streptomyces aureofaciens sigma factor RpoZ. Gene 208, 43-50.
2. , Rezuchova, B., Kormanec, J. (2001) A two-plasmid system for identification of promoters recognized by RNA polymerase containing extracytoplasmic stress response RpoE in Escherichia coli. J. Microbiol. Methods 45, 103-111.
3. Sevcikova, B., Benada, O., Kofronova, O., Kormanec, J. (2001) Stress-response sigma factor SigH is essential for morphological differentiation of Streptomyces coelicolor A3(2). Arch. Microbiol. 177, 98-106.