Fields of research
Collection of microorganisms
Molecular mechanisms of adaptation of Listeria monocytogenes for intracellular replication
It is evident that the intracellular space differs from an environment in a number of important for bacteria factors such as nutrient composition and availability, temperature, risk factors etc. To survive in the intracellular space, facultative intracellular parasites such as Listeria monocytogenes have to switch certain metabolic processes. The final goal of our study is to establish general metabolic pathways involved in adaptation to intracellular multiplication.
Project is supported by President's grant for supporting the leading science institutes НШ-5447.2008.7 «Molecular-genetic bases of bacterial virulence»
- Sapenko T., Vazquez-Boland J.A., Ermolaeva S. ActA releasing into the medium is due to membrane anchor cleavage.// Abstr. ISOPOL XV., Uppsala, Sweeden September 12-15, 2004 Abstr.21
- Sapenko T., Vazquez-Boland J.-A., Ermolaeva S. Proteolytic release of membrane-anchored proteins in Listeria monocytogenes and its role in the virulence // Abstr. 30th FEBS Congress. Budapesht, Hungary. July 2-7, 2005. p. 180
Plasma medicine: application to the therapy of wound infection” (in collaboration with Joint Institute of High Temperatures, Moscow, Russia). Supported by Russian Ministry of Science and Innovations (grant 02.740.11.0310). Co-ordinator: O.F Petrov. Total budget 9 000 000 Rub (about 220 000 Euro).
Research in Plasma Medicine was initiated in collaboration with Joint Institute of High Temperatures, Moscow, Russia, and Max-Planck Institute of Extraterrestrial Physics, Munich, Germany, in 2008.
The project is aimed to develop technology of plasma application to infection wound treatment.
The following studies are in progress:
- Effectiveness of plasma against intracellular pathogens; particularly Chlamydia spp
- Interactions of plasma with eukaryotic cells; particularly, signalling events developing in eukaryotic cells upon plasma treatment and their consequences
- Mechanisms of plasma interactions with biological objects
- Effects of surface protein composition on bacterial susceptibility to plasma treatment
- Bactericidal effects of argon nonthermal plasma in vitro were demonstrated for both Gram-negative and Gram-positive pathogenic bacteria of different species including Pseudomonas aeruginosa, Burkholderia cenocepacia, Staphylococcus aureus, S. epidermis, Streptococcus pyogenes etc. In whole, Gram-negative bacteria were more susceptible to a plasma treatment than Gram-positive bacteria.
- Plasma effects on pathogenic bacteria in biofilms were studied. Biofilms partly protected bacteria, the efficiency of protection was dependent on their thickness. Bacteria in deeper biofilm layers survived better after the plasma treatment.
- A rat model of a superficial slash wound infected with P. aeruginosa and S. aureus was developed to assess the efficiency of argon plasma treatment in vivo. A statistically significant increase in the rate of wound closure was observed in plasma-treated animals during a plasma course.
Development of a novel strategy of antimicrobial therapy to control chronic infections. Supported by Russian Ministry of Science and Innovations (grant 02.740.11.0310). Co-ordinator: S. Ermolaeva. Total budget 13 000 000 Rub (about 325 000 Euro)
The ultimate goal of the project is development of new approaches to the therapy of chronic infections, which would be based on disruption of major mechanisms responsible for conversion of the acute to chronic infection. These two mechanisms is formation of biofilms by extracellular pathogenic bacteria and intracellular parasitism. Combination of chemical and physical antibacterial treatments is considered as a most promising approach. Application of Nonthermal plasma in combination with chemical treatments is under investigation.
- Ermolaeva S, Varfolomeev A, Chernukha M, Yurov D, Vasiliev M, Kaminskaya A, Moisenovich M, Romanova J, Murashev AM, Selezneva I, Shimizu T, Sysolyatina E, Shaginyan I, Petrov O, Mayevsky E, Fortov V, Morfill G, Naroditsky B, Gintsburg A. Bactericidal effects of non-thermal argon plasma in vitro, in biofilms and in the animal model of infected wounds. J. Med. Microbiol. 2011. 60:75-83
- Ermolaeva S., Tuhvatullin A., Varfolomeev A., Vasiliev M., Logunov D., Petrov O., Morfill G., Fortov V., Naroditsky B., Gintsburg A.,Effects of nonthermal plasma on signaling events in the eukaryotic cell, 3rd International Conference on Plasma Medicine (ICPM3), Greifswald, Germany, September 19-24, 2010
- S. Ermolaeva, O. Petrov, N. Zigangirova, A. Varfolomeev, M. Vasiliev, N. Kolkova, E. Fortov, G. Morfill, B. Naroditsky, A. Gintsburg,Effects of nonthermal argon plasma on intracellular pathogens and host cells, 3rd International Conference on Plasma Medicine (ICPM3), Greifswald, Germany, September 19-24, 2010
The role for proteases with intramembrane activity in virulence of pathogenic bacteria
Molecular bases of polypathogenecity of infectious agents
Polypathogenecity is an ability of pathogenic bacteria to cause a disease in hosts, which belong to differed species and/or taxons.
The main tasks of the research are:
- comparative analysis of the role that virulence factors play in infection of high eukaryotes and protozoa on the model of Listeria monocytogenes;
- establishment of the role for biofilms in interactions between pathogenic Burkholderia and protozoa;
- study of adaptive variability of genes encoding invasion factors of L. monocytogenes and Y. enterocolitica, isolated from different sources;
- analysis of correlations between virulence gene alleles and host-specific variability of eukaryotic receptors;
- comparative analysis of signalling pathways activated by intracellular parasites in high and lower eukaryotes.
- RFBR grant 06-04-49287-а «The role for bacterial virulence factors in interpopulation interactions betweeb pathogenic bacteria and protozoa»
- President's grant for support the leading science institutes НШ-5447.2008.7 «Molecular-genetic bases of bacterial virulence»
- Pushkareva V., Mayatskaya A., Ermolaeva S. Whether pathogenic bacteria are pathogenic for protozoa? A model study on interactions of Listeria monocytogenes with free-living protozoa. // // Abstr. ISME – 11, Vienna, Austria, August 20-25, 2006
The input of modulations in virulence gene expression into development of intracellular infection.
The main goal: Establishment of mechanisms and the principal role of modulations in expression of bacterial virulence factors in development of intracellular infection and a response of the host cell on the model of Listeria monocytogenes.
Supported by President's grant for young investigators (МД-2518.2005.4
- Ermolaeva S.A., Belyi Yu.F., Tartakovskii I.S. Changes in the level of expression of Listeria monocytogenes virulence factors under environmental influence. Mol. Gen. Microbiol. Vir. (in Russian), 2000, (1): 17-19
- Ermolaeva S.A. Genetic mechanisms of virulence in Listeria monocytogenes. Review. Genetika. (in Russian), 2001, 37:286-293
- Ermolaeva S.A., Tartakovskii I.S. Regulation of virulence factor expression in Listeria monocytogenes. Review. J. Microbiol.Epidemiol.Immunol. (in Russian), 2001, (3):106-110
Releasing of membrane-anchored proteins and its role in Listeria monocytogenes virulence
Hypothesis: Membrane-anchored Listeria monocytogenes virulence factors are released into the medium in a tightly regulated way, and the role of the released forms in virulence is different from the surface attached ones.
Supported by International Society for Infectious Diseases grant (Spring 2005)
- 1.Sapenko T., Vazquez-Boland J.-A., Ermolaeva S. Proteolytic release of membrane-anchored proteins in Listeria monocytogenes and its role in the virulence // Abstr. 30th FEBS Congress. Budapesht, Hungary. July 2-7, 2005. p. 180