Wayne L. Nicholson
Description of Research
General area: Dr. Nicholson’s laboratory studies mechanisms of bacterial spore resistance and longevity, the survival and proliferation of microorganisms in extreme extraterrestrial environments, and microbial evolution in novel environments.
Mechanisms of bacterial spore resistance and longevity.
Bacterial endospores are the longest-lived cells known, and exhibit a high degree of resistance to extremes of temperature, desiccation, pressure, and radiation over extended time periods. Spore DNA is a major target lethal and mutagenic damage, and research in our lab concentrates on mechanisms that protect spore DNA from damage and by which DNA damage is repaired during spore germination, using the model organism Bacillus subtilis. Understanding spore resistance has important applications in a variety of fields ranging from public health and bioterrorism to geomicrobiology and astrobiology.
Survival and proliferation of microorganisms in extreme extraterrestrial environments.
A portion of the spore resistance and longevity research in our lab is concentrated on placing physical constraints on lithopanspermia theory, which postulates the transfer of viable microorganisms between planets as the result of natural impact processes. Such research has important implications in the fields of astrobiology and in planetary protection research.
Microbial evolution in novel environments.
We have been conducting laboratory-scale evolution experiments of B. subtilis cells cultivated for thousands of generations in the presence or absence of strong selective pressure for sporulation. We have uncovered a number of interesting processes which occur during bacterial evolution. We have isolated a number of spontaneous mutations in the RNA polymerase beta subunit that cause global changes in B. subtilis cell physiology and transcription. Our current plans are to extend these studies to microbial evolution in the space environment.
- Teaching Interests
- MCB 6457 - Metabolic Regulation