Protein -Dna Interactions Required for Regulation of the Proline Utilization Operon in Salmonella

245 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2001.A modification of the S&barbelow;ystematic E&barbelow;volution of L&barbelow;igands by Exponential Enrichment (SELEX) approach was used to enrich for put control DNA molecules defective in PutA binding in vitro. These experiments identified nucleotide residues that may be important for the specificity of the PutA-put control region interaction. Using the lambda Red system, the wild-type put control region in the LT2 chromosome was replaced with the mutant put control region isolated by SELEX. The effects of the mutations in vivo was analyzed by proline dehydrogenase assays and beta-galactosidase assays using a putA::MudJ fusion downstream of each of the put control region mutant. Although the mutations isolated in the put control region are defective in PutA binding in vitro, they do not show a strong defect in vivo..U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD