TU Berlin

Environmental MicrobiologyInvestigation of dormant states of the predominant biofilm in drinking water

Umweltmikrobiologie Logo, Wassertropfen unter Lupe betrachtet

Page Content

to Navigation

Study of the physiological states associated with the dormant states of the predominant bacterial species that form biofilms in tap water

Bacteria have developed various strategies of survival in adverse environments, e.g. through dormant states. Persistence" and the "viable but non-cultivable" state are the two phenotypes that have been described for prolonged stays in unfavorable environments.

Biofilms are communities where intense interactions take place, and which are crucial for survival and persistence under limiting conditions. From a public health point of view, biofilms represent a problem as a possible source of pathogenic bacteria, because they confer resistance and tolerance to disinfectants. Due to these characteristics it is difficult to remove biofilms and associated pathogens from main and household distribution systems. Therefore, biofilms of microorganisms with a very high proportion of individuals adapted to drinking water conditions (VBNC-state) are ideal to study survival of pathogens in these environments.

In this project, we are working with Aquabacterium commune biofilm in continuous reactors with flow characteristics similar to the flow conditions in the drinking water distribution system. Reactor characteristics such as mixing level and residence time during establishment of the biofilms are tested. Techniques such as confocal laser scanning microscopy, fluorescence microscopy, flow cytometry and qPCR-PMA are being used to characterize growth and shift into various physiological states.

A. commune is one of the most predominant bacteria in the water systems of Germany and Sweden, and besides being a good biofilm former it is also described to persist in the drinking water distribution system in the VBNC state. These biofilms will be used in further studies to evaluate the efficacy of disinfectants and antibiotics and to analyze more complex communities as double-species biofilms (work in progress).


Quick Access

Schnellnavigation zur Seite über Nummerneingabe