Thermal Biology Insitute Seminar Series
- Monday, May 5, 2014 at 3:10pm
- Plant Biosciences Building, 108 - view map
Please join us for TBI seminar on Monday, May 5th as we host Dr. Yukari Maezato of Pacific Northwest National Laboratory. Dr. Maezato will present, Study of Catobolite Repression in Archaeon Sulfolobus solfataricus. Seminar is at 3:10pm in 108 Plant Bioscience Building.
Abstract: Sulfolobus solfataricus is an archaeon that thrives in a high temperature and low pH environment. Many Sulfolobus species have been isolated from terrestrial geothermal hot springs. In such places, the environmental factors greatly affect the temperature, pH, and availability of nutrients. To survive in such an environment, organisms must develop efficient strategies to obtain nutrients. Carbon catabolite repression (CCR) is a strategy to ensure optimal carbon metabolism. In this study, we employed Sulfolobus solfataricus as a model system to gain an understanding of the mechanisms of CCR in archaea. We isolated an S. solfataricus CCR mutant through screening for a lactose negative phenotype. Studies of this and related mutants showed that expression of lacS (β-glycosidase) was reduced during growth in repressing media and by mutation of an unlinked locus called "car". Extensive phenotypic study of CCR mutants revealed additional carbon metabolic defects associated with various sugars. In addition, our data indicates that the car mutation also resulted in changes in the expression level of several genes and proteins involved in chromatin remodeling, such as deacetylase and S-adenosylmethionine synthetase (metK). Genomic DNA library (BAC) screening and genome sequencing showed no apparent differences between the wild type and the car mutant. To gain more insight into this phenomenon, chromatin DNA transformation and reconstitution experiments were conducted. The results suggested that the change in the chromatin dynamics affected the car CCR phenotype and that the CCR regulatory mechanism in S. solfataricus operates at the level of chromatin modification.
- Thermal Biology Institute