RUI: Characterization of Salinity Regulated Genes in the Haloarchaeon, Haloferax Volcanii

Rider University, Lawrenceville NJ

Investigators

Abstract

This project aims to better understand the genes and molecular processes necessary for adaptation to high salinities in the halophilic, or irsalt-lovinglo microbe, 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. H. volcanii is a model organism for studying the effects of changes in environmental salinity on gene expression, as this organism grows over a wide range of salt concentrations, between approximately 12% to 30% NaCl. Previous funding by the NSF supported exploratory research to both isolate H. volcanii salt-sensitive mutants and begin preliminary research to characterize genes involved in hypersaline regulation using molecular approaches. This project will continue to build upon previous findings to perform more in-depth analyses. The major objectives of this research are to: 1) identify genes involved in causing the salt-sensitive phenotype of the H. volcanii mutant strains; 2) begin examining the regulatory elements involved in controlling salinity-mediated gene regulation; and 3) characterize and identify the targets of a putative regulatory gene found to be expressed under high salt growth conditions. The broader impacts of this project will both advance discovery through undergraduate teaching and training and broaden the exposure to science of underrepresented minorities. It is anticipated that all of the students who participate in this research will gain valuable experience in the study of molecular biology, microbiology, and genetics that in turn will better prepare them for future careers in science.