Singlet oxygen, a neglected but important environmental factor: short‐term and long‐term effects on bacterioplankton composition in a humic lake
- 3 December 2010
- journal article
- Published by Wiley in Environmental Microbiology
- Vol. 12 (12), 3124-3136
- https://doi.org/10.1111/j.1462-2920.2010.02285.x
Abstract
Photolysis of dissolved organic matter (DOM) leads to contrasting effects on bacterioplankton dynamics, i.e. stimulation and inhibition of bacterial activity. In particular, the role of short-lived reactive oxygen species (ROS), e.g. singlet oxygen (¹O₂), in altering microbial activity and species composition has scarcely been investigated. Therefore, we have artificially increased the natural rate of ¹O₂ formation in short-term (∼4 h) in situ and long-term (72 h) laboratory incubations of surface water samples from a humic acid-rich lake. Denaturing gradient gel electrophoresis (DGGE) patterns revealed significant changes in occurrence of abundant bacterioplankton phylotypes upon ¹O₂ exposure. Cluster analysis of DGGE patterns showed that a moderate increase in ¹O₂ exposure leads to similar changes in different years indicating the establishment of bacterial communities adapted to ¹O₂ exposure. Bacterioplankton phylotypes favoured under these conditions belonged to Betaproteobacteria of the beta II cluster (e.g. Polynucleobacter necessarius) and the beta I cluster related to Limnohabitans (R-BT subcluster) as well as Alphaproteobacteria affiliated to Novosphingobium acidiphilum. In contrast, Actinobacteria of the freshwater acI-B cluster were sensitive even against moderate ¹O₂ exposure. We conclude that ¹O₂ exposure due to DOM photolysis represents an important natural selective factor affecting bacterial species dynamics in aquatic ecosystems in many ways.Keywords
This publication has 81 references indexed in Scilit:
- Limnohabitans planktonicus sp. nov. and Limnohabitans parvus sp. nov., planktonic betaproteobacteria isolated from a freshwater reservoir, and emended description of the genus LimnohabitansInternational Journal of Systematic and Evolutionary Microbiology, 2010
- Involvement of Cell Surface Structures in Size-Independent Grazing Resistance of Freshwater ActinobacteriaApplied and Environmental Microbiology, 2009
- Alteration of chromophoric dissolved organic matter by solar UV radiation causes rapid changes in bacterial community compositionPhotochemical & Photobiological Sciences, 2009
- Emended description of the genus Polynucleobacter and the species Polynucleobacter necessarius and proposal of two subspecies, P. necessarius subsp. necessarius subsp. nov. and P. necessarius subsp. asymbioticus subsp. nov.International Journal of Systematic and Evolutionary Microbiology, 2009
- Interactive effects of solar radiation and dissolved organic matter on bacterial activity and community structureEnvironmental Microbiology, 2007
- Diversity and Seasonal Dynamics of Actinobacteria Populations in Four Lakes in Northeastern GermanyApplied and Environmental Microbiology, 2006
- Predation on prokaryotes in the water column and its ecological implicationsNature Reviews Microbiology, 2005
- A simple remedy against artifactual double bands in denaturing gradient gel electrophoresisJournal of Microbiological Methods, 2004
- Measurement of photogenerated singlet oxygen (1O2(1Δg)) in aqueous solution by specific chemical trapping with sodium 1,3-cyclohexadiene-1,4-diethanoateJournal of Photochemistry and Photobiology B: Biology, 1997
- Basic local alignment search toolJournal of Molecular Biology, 1990