Shantanu Bhatt Isolation and Characterization of hyperosmotically regulated genes in the pulmonary pathogen, Burkholderia cepacia Division Sciences Department Biology Year 2004 Advisor Chris Weingart Funding Sources Not Specified

Hyperosmotically regulated genes, encoding potential virulence factors have been identified in several bacterial species that colonize the lungs of immunocompromised patients. Specifically, sodium chloride regulated genes have been identified in several pulmonary pathogens including Staphylococcus aureus, Pseudomonas aeruginosa and Burkholderia pseudomallei. Another opportunistic pulmonary pathogen, Burkholderia cepacia inhabits the lungs of cystic fibrosis (CF) patients. However, very little is known about salt regulation in B.cepacia.  In this report we use transposon mutagenesis to identify the genes in B.cepacia K56-2 strain that are induced by a hyperosmotic sodium chloride environment. Over 30 transconjugants expressing higher amounts of lacZ gene at hyperosmotic sodium chloride concentration were identified. The β-galactosidase assay was performed on the transconjugants so as to quantify the visually observed variable expression of β-galactosidase in the different salt environments. 4 of these 33 transconjugants showed a 2-5 fold higher β-galactosidase activity in the hyperosmotic sodium chloride environment. Further research needs to be done in order to sequence the gene and also to identify the protein encoded by the gene and its potential function.