Title: | Bacterial community composition associated with freshwater algae: species specificity vs. dependency on environmental conditions and source community |
Author(s): | Eigemann F; Hilt S; Salka I; Grossart HP; |
Address: | "Leibniz-Institute for Freshwater Ecology and Inland Fisheries, Berlin, Germany. eigemann@igb-berlin.de" |
ISSN/ISBN: | 1574-6941 (Electronic) 0168-6496 (Linking) |
Abstract: | "We studied bacterial associations with the green alga Desmodesmus armatus and the diatom Stephanodiscus minutulus under changing environmental conditions and bacterial source communities, to evaluate whether bacteria-algae associations are species-specific or more generalized and determined by external factors. Axenic and xenic algae were incubated in situ with and without allelopathically active macrophytes, and in the laboratory with sterile and nonsterile lake water and an allelochemical, tannic acid (TA). Bacterial community composition (BCC) of algae-associated bacteria was analyzed by denaturing gradient gel electrophoresis (DGGE), nonmetric multidimensional scaling, cluster analyses, and sequencing of DGGE bands. BCC of xenic algal cultures of both species were not significantly affected by changes in their environment or bacterial source community, except in the case of TA additions. Species-specific interactions therefore appear to overrule the effects of environmental conditions and source communities. The BCC of xenic and axenic D. armatus cultures subjected to in situ bacterial colonization, however, had lower similarities (ca. 55%), indicating that bacterial precolonization is a strong factor for bacteria-algae associations irrespective of environmental conditions and source community. Our findings emphasize the ecological importance of species-specific bacteria-algae associations with important repercussions for other processes, such as the remineralization of nutrients, and organic matter dynamics" |
Keywords: | Axenic Culture Bacteria/classification/*isolation & purification Biota Chlorophyta/growth & development/*microbiology Cluster Analysis Denaturing Gradient Gel Electrophoresis Diatoms/growth & development/*microbiology Environment Fresh Water/*microbiology; |
Notes: | "MedlineEigemann, Falk Hilt, Sabine Salka, Ivette Grossart, Hans-Peter eng Research Support, Non-U.S. Gov't England 2012/10/04 FEMS Microbiol Ecol. 2013 Mar; 83(3):650-63. doi: 10.1111/1574-6941.12022. Epub 2012 Oct 24" |