Headed by Professor Leiv Sigve Håvarstein, this group aims at understanding the mechanisms of natural genetic transformation in different strains of Streptocococcus pneumonia and other naturally competent Streptococci. This Gram-positive, invasive bacteria is the cause of medical conditions like pneumonia, meningitis, otitis media, sinusitis and others, and more than 90 serotypes are known.
Leiv Sigve Håvarstein
Foto: Hanne Israelsen
Transformation by horizontal gene transfer has been an underestimated factor in the evolution of life on earth. Understanding the mechanisms involved in this uptake of free DNA by bacterial cells (gene transfer between organisms without reproduction) will shed light on and hopefully help solve the problems of antibiotic resistance and transfer of pathogenicity and virulence.
Also, the communication between single bacteria in a population, and how this communication determines the organisms behaviour, is on the groups agenda. Small peptide pheromones are produced by different strains in a population and participate in a complicated “conversation”. The group aims at understanding and eventually controlling such mechanisms. Long term, the results may have strong implications on health issues.
Streptococcus thermophilus is the economically second most important lactic acid bacteria after Lactococcus lactis. The aim of the group is to develop molecular tools for studying the genetics and metabolism of this species of bacteria. The hope is to use this knowledge to develop better starter cultures for use in the dairy industry.
Main research projects:
Pneumococcal transformation Using surface plasmon resonance equipment, mass spectroscopy, array-based transcription profiling as well as classical molecular biology methods, this project will unravel fundamental aspects of natural competence, antibiotic resistance as well as virulence in Streptococcus pneumonia. Read more...
Streptococcus thermophilus These lactic acid bacteria, commonly used in the food industry, are studied in a present project. Providing tools for molecular research is one of the main objects. This organism seems to contain the genes needed for natural transformation, but has not been shown to possess this property so far. Being able to control this, will mean very interesting possibilities for future tailormaking of dairy products. The genetic basis for the properties of S. thermophilus like sugar and protein metabolism, polysaccharide production and flavour generation has only recently been determined, and more information are required to enhance stability of the desired traits during production.
The group is a member of one of the FUGE (Norwegian) technology platforms called CAMST - Consortium for Advanced Microbial Sciences and Technologies. The consortium aims at establishing and improving a national infrastructure for microbiological research.
