Intestinal Bacteria Research
Basic research at USU is aimed at understanding especially harmful enteric bacteria.
Pathogenic Gram-negative enteric bacteria pose a serious health threat not only to deployed service members, but also to endemic populations and visiting workers. These bacteria are an area of focus for several USU researchers.
Paul Rick, Ph.D., chair of USU's Department of Biochemistry and Molecular Biology, and his team focus on membrane biogenesis. Specifically, they study the genetics, biosynthesis and assembly of enterobacterial common antigen (ECA), a cell-surface glycolipid present in all Gram-negative enteric bacteria.
Determining How ECA Moves
Among their many accomplishments, Rick's laboratory has identified the location and function of many of the genes involved in the assembly of ECA. The researchers have discovered that ECA is assembled in association with the inner (cytoplasmic) cell membrane, but that it is subsequently translocated to the outer membrane. They now seek to uncover the mechanisms involved in this process.
In one aspect of this work, they have identified a protein called a "flippase" that is responsible for transferring precursors of ECA through the cytoplasmic membrane. Currently, they are working to determine the mechanism of the flippase.
Investigating ECA's Resistance to Bile Salts
One of the properties of Gram-negative enteric bacteria that enables them to survive in the gastrointestinal tract of animals and humans is their resistance to bile salts. The linear cell-surface form of ECA appears to contribute to this resistance. The researchers hope that their work will lead them to uncover ways to inhibit the bile salts-resistance of pathogenic Gram-negative enteric bacteria.
Detecting Contamination
Additionally, Rick is working with USU researcher Anthony Maurelli, Ph.D., to develop a rapid and sensitive assay to detect ECA. Such an assay would allow the specific detection of Gram-negative enteric bacteria. It could have a number of important applications, including the development of a rapid test for detecting contaminated food.