Dr. David Schleheck, University of Konstanz, Department of Biological Sciences, P.O. box 649, Universitätsstrasse 10, Postfach 649, Konstanz, Germany, 78457.
Photoautotrophic–heterotrophic biofilm communities: a laboratory incubator designed for growing axenic diatoms and bacteria in defined mixed-species biofilms
Article first published online: 14 DEC 2011
© 2011 Society for Applied Microbiology and Blackwell Publishing Ltd
Environmental Microbiology Reports
Thematic issue: Taxonomy and Biodiversity
Volume 4, Issue 1, pages 133–140, February 2012
How to Cite
Buhmann, M., Kroth, P. G. and Schleheck, D. (2012), Photoautotrophic–heterotrophic biofilm communities: a laboratory incubator designed for growing axenic diatoms and bacteria in defined mixed-species biofilms. Environmental Microbiology Reports, 4: 133–140. doi: 10.1111/j.1758-2229.2011.00315.x
- Issue published online: 7 FEB 2012
- Article first published online: 14 DEC 2011
- Received 7 July, 2011; accepted 14 November, 2011.
Biofilm communities in the euphotic zone of aquatic habitats comprise photoautotrophic microorganisms, such as diatoms, green algae and cyanobacteria, which produce the organic carbon that fuels the life of a heterotrophic contingent of microorganisms, mostly bacteria. Such photoautotrophic–heterotrophic mixed-species biofilms have received little attention in biofilm research due to a lack of suitable pure-culture laboratory model systems. However, they offer important insight into microbial population dynamics and community interactions during a biofilm-developmental process that shapes highly structured, extremely well-adapted microbial landscapes. Here, we report on the development of a sterile incubation chamber for growing and monitoring axenic phototrophic biofilms, i.e. a sterilizable, illuminated, continuous-flow system for a routine work with pure cultures. The system has been designed to simulate the growth conditions in the shallow, littoral zone of aquatic habitats (horizontal surface, submerged in water, illuminated, aerated). Additional features of the concept include automated photometrical monitoring of biofilm density (as biofilm turbidity), analysis via confocal microscopy, direct harvesting of cells, and options to control illumination, flow velocity, and composition of culture fluid. The application of the system was demonstrated in growth experiments using axenic diatom biofilms, or axenic diatom biofilms co-cultivated with different bacterial strains isolated from epilithic biofilms of an oligotrophic freshwater lake.