It is based on detecting short, repetitive DNA segments in the genome of bacteria. Every single bacterial strain has such characteristic repeats. "With this method we are able to identify bacterial strains as well as clarify their genetic relationships. Furthermore, we can show how new pathogenic variants develop," says Manfred Hfle, researcher at the HZI. The results have now been published in the current issue of the scientific journal "Applied and Environmental Microbiology". The work is part of the two European Union funded projects "Healthy Water" and "AQUA-chip". Manfred Hfle is coordinator of both projects that deal with various aspects of the microbiological safety of both, drinking water and sea water.
Various bacteria that live in drinking water or sea water can cause severe human diseases. One of them are vibrios: its species Vibrio cholerae is more commonly known as the causative agent of Cholera that spread in Europe until the 20th century. Interestingly, not all Vibrio cholerae strains are pathogenic to humans. Only those strains cause severe diarrhoea known as Cholera that produce a certain bacterial toxin which attacks the intestinal wall. A less known, though also dangerous member of the genus Vibrio, is Vibrio parahaemolyticus. It is a highly contagious pathogenic germ with only a dozen ingested bacteria causing severe diarrhoea. This strain is a threat for the pacific region and reached the east coast of the United States in the 21st century. Since the end of the 1990s, Vibrio parahaemolyticus epidemics have led to thousands of cases of illness in Chile. In the future, due to ballast water or climate change, the species may also gain importance in Europe. As in the Cholera bacterium, various Vibrio parahaemolyticus strains exist with varying infectivity. Distinguishing those strains has been a challenge until now.
The newly developed method makes it now possible to characterize and distinguish hundreds of bacteria str
|Contact: Dr. Bastian Dornbach|
Helmholtz Association of German Research Centres