Abigail A. Salyers (1942 – 2013) was a microbiologist who pioneered the field of human microbiome research. Her work on the bacterial phylum Bacteroidetes and its ecology led to a better understanding of antibiotic resistance and mobile genetic elements. At a time where the prevailing paradigm was focused on E. coli as a model organism, Salyers emphasized the importance of investigating the breadth of microbial diversity. She was one of the first to conceptualize the human body as a microbial ecosystem. Over the course of her 40-year career, she was presented with numerous awards for teaching and research and an honorary degree from ETH Zurich, and served as president of the American Society for Microbiology.
Education
Abigail Salyers was born in Louisville, Kentucky and attended high school in Arlington, Virginia at Wakefield High School. During high school, she was at risk of expulsion due to being pregnant, but she graduated in 1959 and with the help of her English teacher, Mrs. Baker, applied to college. Salyers went on to receive her undergraduate degree in Mathematics in 1963 and a Ph.D. in Nuclear Physics in 1969 from George Washington University, Washington, D.C.
Career
Four years into her first academic position teaching and researching physics at St. Mary's College, Salyers chose to switch her focus to microbiology as a post-doctoral researcher at Virginia Polytech Institute. She began to study the metabolism of the anaerobic microbes of the human intestinal tract, particularly the anaerobic bacterium Bacteroidetes. In 1978, Salyers started her own lab at the University of Illinois at Urbana-Champaign. There she met her long-time life partner and fellow professor Jeffrey Gardner, as well as her research associate and collaborator Nadja Shoemaker. In 1983, she became the first woman professor in the Microbiology Department to be granted tenure, and in 1988 was promoted to full professor. In 2004, she was named the G. William Arends Professor in Molecular and Cellular Biology.
As a lecturer at the University of Illinois, Salyers worked tirelessly to revitalize the inaccessible medical school curriculum. In her teaching, she emphasized the importance of microbiology as the defining biological discipline of the coming decades and its relevance to her students. To accompany her work in the classroom, she co-authored the textbook Bacterial Pathogenesis: A Molecular Approach with Dixie Whitt, with whom later collaborations followed. As a result of her educational efforts, Salyers was invited to be Co-Director of the Microbial Diversity Summer Course at the Marine Biological Laboratory in Woods Hole, MA for the summers of 1995–1999.
Salyers’ microbiome research was based in the study of the physiology of the anaerobic bacterium Bacteroides, with particular regard to their carbohydrate metabolism and their ability to harbor mobile antibiotic resistance genes. Her lab at the University of Illinois at Urbana-Champaign developed genetic tools that helped to expanded on her earlier research on polysaccharide transport and fermentation in Bacteroidetes. These tools fueled the discovery of the processes though which the bacterium sequesters complex carbohydrates inside the cell and anaerobically degrades them. In the human colon, these metabolic processes result in important byproducts which are utilized by other gut microflora and by the human host. In developing these genetic tools, Salyers’ lab discovered conjugative transposons, a type of mobile genetic element which can transfer genes for antibiotic resistance among gut bacteria. Initially, they used transposons as markers for genetic analysis. But Salyers also realized that transposons could carry antibiotic resistance genes between microbial cells in the human gut. They investigated the tightly regulated molecular mechanisms of the horizontal transfer of these mobile antibiotic resistance genes and discovered that Bacteroides acted as a reservoir of these genes in the human colon. The many tools that Salyers developed to work with her “funny bugs” and the discoveries she made are responsible for the prominence of Bacteroidetes as a model organism in microbiology today.