Marine metaproteomics - from simple to complex microbial assemblages


Thursday, June 28, 2012
Redfield Auditorium - 12:00 Noon
Ms. Antje Gardebrecht
University of Greifswald, Germany

In situ studies on microbial community and expression dynamics are becoming increasingly important in our effort to overcome the bottleneck of unculturable microorganisms. Based on two examples of metaproteomic analyses, it will be demonstrated that advanced mass spectrometry technologies and specific habitat-related metagenome databases are indispensable prerequisites for the identification and interpretation of representative physiological patterns in environmental samples.

Symbiont assemblages isolated from deep-sea tubeworms comprise low-complexity model systems for whole-population proteomics and have therefore been the major research target of a recent study that resolved functional variations between monospecific bacteria residing in two different hosts. When dealing with highly complex environmental samples, such as marine bacterioplankton communities, additional enhanced strategies are required to effectively facilitate protein extraction, quantification and classification. During the investigation of the bacterial response to a phytoplankton bloom in German coastal waters, high-resolution proteomics provided insights into the functional succession of microbial populations at genus level. Variations in substrate availability were directly reflected by shifts in key protein expression, which were related to adaptations to prevailing environmental conditions.

As a result, growing experience with metaproteomic data from various habitats might extend our present knowledge on ecological interactions and allow for the definition of molecular indicators specific for environmental situations.