The Simons Foundation has selected MBL Assistant Scientist Emil Ruff for a 2021 Early Career Investigator in Marine Microbial Ecology and Evolution Award.
This three-year award will fund continued research on novel lineages of Chlorobi, bacteria that Ruff previously sampled from Trunk River in Falmouth, Mass., and investigated with members of his lab and with students and faculty of the MBL’s Microbial Diversity course.
Members of the Chlorobi phylum, they discovered, are mostly responsible for the yellow microbial blooms that can be seen floating in the brackish Trunk River lagoon. This was a surprising discovery since Chlorobi generally do not grow in the presence of oxygen.
Finding them in mildly oxic waters led the researchers to examine the bloom microbes and their genomes more closely. This analysis suggested mutualistic interactions between the sulfur-oxidizing phototrophs and sulfur-reducing bacteria, which were co-enriched in the bloom layer.
These interactions, they propose, allow the oxygen-sensitive microbes to thrive in an otherwise unfavorable habitat.
During the Simons Award period, Ruff and colleagues will investigate the genomic, (eco)physiological and biochemical underpinnings of the involved organisms and interactions.
“A partnership that allows anaerobic organisms to thrive in a hypoxic water body has implications for our understanding of the evolution of the geo- and biosphere, as it may have been a mechanism for anaerobes to adapt to the oxidation of the atmosphere and oceans caused by the Great Oxidation Event,” Ruff proposes. “Building a partnership is much less costly and much faster than the de novo evolution of the necessary metabolic traits, and hence represents a strategy to quickly adapt to new conditions, including the environmental disturbances caused by global change.”
Top Photo: Emil Ruff processing samples at Trunk River, Falmouth, Mass. Photo: Elise Cowley