POWRE: Isolation and characterization of salt-sensitive mutants in the archaeal halophile, Haloferax volcanii

点击翻译按钮获取中文摘要

This POWRE project focuses on the isolation and characterization of salt-sensitive mutants of the halophilic Archaeon, Haloferax volcanii. The extreme halophiles belonging to the domain Archaea require salt concentrations for growth that range from -1.5 M up to 5.2 M NaCl, an upper limit in excess of ten times the salinity of seawater. Halophiles are found in such hostile environments as the Dead Sea and the Great Salt Lake, where high concentrations of salt preclude the growth of almost all other known organisms. To date, there are no documented reports that have used genetic techniques such as mutagenesis with the specific intent of creating salt-sensitive mutants in the halophilic Archaea. In this study, gene disruption mutagenesis will be performed to obtain H. volcanii mutants that are no longer capable of growing at 3.5 M NaCl, the optimal salt concentration for this organism. Mutants will be analyzed to determine the specific location of the gene(s) that was disrupted to cause the salt-sensitive phenotype. The gene(s) responsible for salt- sensitivity will be identified and characterized. Preliminary studies will be conducted on these genes to determine how they are regulated in response to salinity in the environment. The data gathered will lead to future studies examining gene regulation in the extreme halophiles. This study will provide the first crucial steps towards understanding how the halophiles are able to adapt in vivo to hypersaline environments on the molecular level. Furthermore, any genetic information that can be gathered about the adaptational mechanisms used by the Archaea to combat the effects of the harsh environments they inhabit is of importance. This project is of an exploratory nature and has the potential to advance Dr. Bidle's career under the objectives of the POWRE program.