Mary Ann Moran is a marine microbial ecologist recognized for her work on the roles of bacteria in the global carbon and sulfur cycles. She is particularly known for her research on bacterial degradation of organic sulfur compounds that participate in ocean-atmosphere flux, bacterial transformation of organic matter dissolved in seawater, and the integration of molecular biology methods into microbial ecology studies. She was born in Boston, Massachusetts and grew up in Huntington, New York. She earned a degree in biology at Colgate University and an M.S. in natural resources at Cornell University. She obtained a Ph.D. in ecology at the University of Georgia in 1987, where she was a postdoctoral fellow in microbiology and became member of the marine sciences faculty in 1993. She is a fellow of the American Association for the Advancement of Science and the American Academy of Microbiology.

Research Interests

Mary Ann Moran's laboratory studies the ecological and genetic basis of marine bacterial carbon and sulfur transformation. They have worked to advance understanding of the functions of marine bacteria in ocean element cycling and the formation and flux of climatically active gases. Coastal marine bacterium Ruegeria pomeroyi was isolated by the laboratory in 1998 and the generation of an early genome sequence supported its development into a model organism for physiological and genetic studies of ocean processes. R. pomeroyi was the basis of the discovery of the biochemical pathways and ecological constraints of bacterial conversion of dimethylsulfoniopropionate, one of the most abundant metabolites produced in the surface ocean and an important source of climate-active sulfur compounds. The ecological role of other compounds making up the diverse pool of metabolites passing between members of the surface ocean microbiome have been characterized, including compounds formed from photochemical reactions in surface seawater and synthesized by marine phytoplankton. The development and quantitation of transcriptome analysis methods for mixed microbial communities have identified factors that regulate function and affect viability of ocean bacteria.

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Primary Section

Section 63: Environmental Sciences and Ecology

Secondary Section

Section 44: Microbial Biology