Dr. Marc Mußmann
Main Research interests
- Biology and ecogenomics of the bacterial taxon Woeseiales, key players in global marine sediments (FWF-funded 2018 - 2022, project # P31010 )
These bacteria are tiny but account for more than 10 million cells in 1 g of beach sand. Because of their ubiquity and their high cell numbers they are expected to substantially impact element cycles in sediments worldwide (Mußmann et al. 2017). It is thus counterintuitive that the Woeseiaceae can hardly be grown and maintained in the laboratory to study their biology in detail. In this project we systematically study the function of Woeseiaceae in nature. We apply modern genetic tools, sequencing of DNA and RNA recovered from the seafloor, which promises unprecedented insights into their actual function and why these bacteria are so successful in marine sediment and what they live from. First results suggest that the Woeseiaceae live well on sugars and proteins, while breathing oxygen and CO2 - just like human beings. But Woeseiaceae are special: it appears that some thrive also on hydrogen, sulfur, nitrite and rusty iron.
Mußmann et al. (2017, ISME J)
2. Iron-cycling microorganisms in coastal surface sediments
Marine sediments contain substantial amounts of magnetic iron, mostly magnetite (Fe3O4). We investigate, whether and how microbes (e.g., the Woeseiaceae) use this as energy source for oxidation, as electron acceptor for respiration or as a rechargeable electron reservoir. Using strong magnets we pull out magnetic particles from diverse coastal sediments and study the microorganisms specifically colonizing particulate iron.