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Researchers Database

You have entered the IISP: Interactive Information System on Pathogenomics


If you would like to insert information about your research or research group, please click to the following link to download the form. After filling it out, please send back to or

Here you will find information about Research groups in the PathoGenoMics fields from the ERA-NET partner countries (Austria, Finland, France, Hungary, Israel, Latvia, Portugal, Slovenia and Spain).
This information is supposed to support cooperation between researchers from different European countries
and thus enhance the development of a European Research Area for PathoGenoMics .


The following information is available and can be searched for:

  • researcher names
  • Institution of the respective researcher, city and country of his/her institution
  • Contact data of the researcher (address, phone, email)
  • Research topics and studied microorganisms of the researcher
  • Special techniques applied by the researcher
  • Potential cooperation topics suggested by the researcher

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Name: PhD Hartke, Axel
Address: Laboratoire de Microbiology de l'Environnement USC INRA 2017; EA956 Université de Caen Esplanade de la Paix F-14150 CAEN Cedex
Institution: Laboratoire de Microbiology de l'Environnement
City: Caen Cedex Zip: 14150
Country: France Phone: 33 (0)2 31 56 54 04
    Fax: 33(0)2 31 56 53 11


Research Topics:
E. faecalis and E. faecium species are natural members of the digestive microflora in humans. Interestingly, they are also found as members of the natural microflora of a variety of fermented food products. The genus Enterococcus is very controversial among lactic acid bacteria. Indeed, while not regarded as particularly virulent organisms, both species are emerging as a major cause of nosocomial infections. Intrinsic tolerance to several classes of antibiotics and increasing acquisition of resistance to most antibiotics in use, contribute to their emergence as prominent nosocomial pathogens. They are the second most common cause of nosocomial blood infections in the United States and the fourth in Europe. E. faecalis accounts for 60 to 80% of enterococcal infections, and is mainly responsible for urinary tract infections, bacteremia, intra-abdominal infections, and endocarditis. Enterococci are well equipped to thrive in an over-medicated environment due to their intrinsic resistance to chemical and physical stresses and antibiotics. It is reasonable to assume that resistance to environmental stresses of these organisms is important for virulence. Therefore one topic of research of the laboratory is to study the underlying molecular mechanisms in E. faecalis. Since exposition of invading pathogens to reactive oxygen and nitrogen intermediates is an important part for the first line defence of the immune system, the molecular analysis of the oxidative stress response is of special interest. Furthermore, oxidative stress has also been implicated as one of the mechanisms whereby bactericidal antibiotics kill bacteria. By systematically screening mutants affected in genes coding anti-oxidative activities we showed recently that the superoxide dismutase is essential for tolerance to vancomycine and penicilline (Bizzini et al. 2009). Understanding on the molecular level of the bactericidal effect of these antibiotics may provide targets for anti-microbial potentiation or the development of new anti-microbial drugs. The capacity of Enterococci to cause disease is based on many subtle virulence/fitness factors. Despite substantial advances in our knowledge concerning some of them, one area that needs greater attention is how the bacterium regulates expression of these factors during infection. Since virulence of enterococci is a multifactorial process, regulatory and signalling molecules are attractive drug targets since their inactivation can lead to pleiotropic effects on expression of virulence/fitness factors. Therefore, characterisation of regulatory genes encoding proteins or non-protein coding RNAs is a further research priority of the laboratory.


Organisms studied:
  • Enterococcus faecalis
  • Enterococcus faecium


Special methods / technologies:
Genomics; Transcriptomics; Proteomics; Mass spectrometry


Suggestions for potential research cooperations:
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