
Steffen Buessecker
Postdoctoral Scholar, Earth System Science
Bio
After graduating from high school (Gymnasium) in Bammental, Germany, I completed my undergraduate degree in Geoecology at the University of Tuebingen. I then moved to Tempe, Arizona, for my Ph.D. in Environmental Life Sciences at Arizona State University before joining Stanford as a postdoc.
Current Research and Scholarly Interests
Driven by anthropogenic global change, extreme environments are spreading, and organisms of the past lived under conditions considered extreme for modern Earth. Thus, extremophilic life processes have been and are becoming increasingly important, demanding research at the edges of biological feasibility.
I approach science questions from the molecular to the ecosystem level, such as (1) how abiotic pathways integrate into biological networks under extreme conditions, (2) what trace metals extremophiles require to maintain metabolic activity, (3) what novel methods can be applied to isolate extremophiles, and (4) how distinct trace gases cycle through extreme natural systems. I am an expert in anaerobic microbial processes and their interconnection with the non-living, abiotic environment. My research interests span across various natural systems, from the tropics to the poles, and into deep time, including the Archean Earth.
All Publications
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An essential role for tungsten in the ecology and evolution of a previously uncultivated lineage of anaerobic, thermophilic Archaea.
Nature communications
2022; 13 (1): 3773
Abstract
Trace metals have been an important ingredient for life throughout Earth's history. Here, we describe the genome-guided cultivation of a member of the elusive archaeal lineage Caldarchaeales (syn. Aigarchaeota), Wolframiiraptor gerlachensis, and its growth dependence on tungsten. A metagenome-assembled genome (MAG) of W. gerlachensis encodes putative tungsten membrane transport systems, as well as pathways for anaerobic oxidation of sugars probably mediated by tungsten-dependent ferredoxin oxidoreductases that are expressed during growth. Catalyzed reporter deposition-fluorescence in-situ hybridization (CARD-FISH) and nanoscale secondary ion mass spectrometry (nanoSIMS) show that W. gerlachensis preferentially assimilates xylose. Phylogenetic analyses of 78 high-quality Wolframiiraptoraceae MAGs from terrestrial and marine hydrothermal systems suggest that tungsten-associated enzymes were present in the last common ancestor of extant Wolframiiraptoraceae. Our observations imply a crucial role for tungsten-dependent metabolism in the origin and evolution of this lineage, and hint at a relic metabolic dependence on this trace metal in early anaerobic thermophiles.
View details for DOI 10.1038/s41467-022-31452-8
View details for PubMedID 35773279