Susan Leschine

Susan Leschine, Ph.D.

Professor Emerita

she, her, hers

Mailing address: 

University of Massachusetts 240 Thatcher Road LSL Room N467 Amherst, MA 01003-9298

Ph.D.:  University of Pittsburgh

Postdoctoral Training: University of Massachusetts Amherst

Microbial Physiology, Technologies for Animal Health, Agriculture and the Environment

Research Interests

Microbial Technologies for Animal Health & Nutrition

Fluorescence micrograph of C. phytofermentans cells interacting with cellulose.

Microbial Metabolism of Complex Carbohydrates

Our research is focused on microbes that convert complex plant polymers into chemicals that have commercial value, such as biofuels, or play a direct role in animal and human health. A significant result of this research is the discovery of a novel family of plant-decomposing bacteria with members found in soil as well as in the intestinal tracts of humans and other animals. We are testing the hypothesis that these microbes link nutrition to health via their metabolism of plant polysaccharides. The intent of our research is to harness the natural diversity of the microbial world to benefit agriculture, the environment, and health.

Microbial Physiology and Diversity: Cellulosic Biomass Decomposition

The diversity of the microbial world is enormous, and microbes constitute a valuable physiological and genetic resource. Our research is aimed at advancing understanding of the biology of diverse microorganisms and interactions among these organisms and their environments.

The most abundant organic materials on Earth are plant structural polysaccharides such as cellulose. The decomposition of these complex carbohydrates is carried out almost exclusively by microorganisms, and is an essential process for human and animal nutrition. Also, plant biomass decomposition forms a key step in the global carbon cycle. A major objective of our research program is to expand our knowledge of the physiology, ecology, and diversity of polysaccharide-decomposing members of microbial communities, to discern the nature of key interactions among community members and with their insoluble substrates, and to understand how these interactions may contribute to the efficient degradation of insoluble polysaccharides.

Much of our research has focused on Clostridium phytofermentans, a bacterium discovered in forest soil near Quabbin Reservoir, that possesses unique properties including the ability to catalyze the direct conversion of plant biomass to ethanol. Based on the capabilities of this microbe, we developed a technology for cellulosic biofuel production. This technology has been licensed by UMass to a Massachusetts biofuels company.

At the Nutrition-Health Interface: Role of Gut Microbiomes.

With the recent explosion of metagenomic data and studies of human and animal microbiomes, it has become apparent that relatives of C. phytofermentans (members of the Lachnospiraceae family) form a significant component of beneficial intestinal microbial communities. This observation has led to the hypothesis that these microbes may form a link between nutrition and health, related to their metabolism and the ability to transform complex plant substances into health-promoting nutrients. In a related project, we are examining the potential of these microbes to enhance the nutritional value of fibrous animal feeds.