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Full-Text Articles in Medicine and Health Sciences
Thymidine-Dependent Staphylococcus Aureus Small-Colony Variants Are Associated With Extensive Alterations In Regulator And Virulence Gene Expression Profiles, Barbara C. Kahl, Gunnar Belling, Petra Becker, Indranil Chatterjee, Katrin Wardecki, Karin Hilgert, Ambrose Cheung
Thymidine-Dependent Staphylococcus Aureus Small-Colony Variants Are Associated With Extensive Alterations In Regulator And Virulence Gene Expression Profiles, Barbara C. Kahl, Gunnar Belling, Petra Becker, Indranil Chatterjee, Katrin Wardecki, Karin Hilgert, Ambrose Cheung
Dartmouth Scholarship
Chronic airway infection is a hallmark of cystic fibrosis (CF) and many CF patients are infected persistently by Staphylococcus aureus. Thymidine-dependent trimethoprim-sulfamethoxazole (SXT)-resistant S. aureus small-colony variants (SCVs), often in combination with isogenic normal S. aureus phenotypes, are highly prevalent and persistent in airway secretions of CF patients due to long-term SXT therapy (B. Kahl, M. Herrmann, A. S. Everding, H. G. Koch, K. Becker, E. Harms, R. A. Proctor, and G.
Requirements For Vibrio Cholerae Hapr Binding And Transcriptional Repression At The Hapr Promoter Are Distinct From Those At The Apha Promoter, Wei Lin, Gabriela Kovacikova, Karen Skorupski
Requirements For Vibrio Cholerae Hapr Binding And Transcriptional Repression At The Hapr Promoter Are Distinct From Those At The Apha Promoter, Wei Lin, Gabriela Kovacikova, Karen Skorupski
Dartmouth Scholarship
Virulence gene expression in certain strains of Vibrio cholerae is regulated in response to cell density by a quorum-sensing cascade that influences the levels of the LuxR homolog HapR through small regulatory RNAs that control the stability of its message. At high cell density, HapR represses the expression of the gene encoding the virulence gene activator AphA by binding to a site between −85 and −58 in the aphA promoter. We show here that a second binding site for HapR lies within the hapR promoter from which it functions to repress its own transcription. This site, as determined by gel …
Rat/Mgra, A Regulator Of Autolysis, Is A Regulator Of Virulence Genes In Staphylococcus Aureus, Susham Ingavale, Willem Van Wamel, Thanh T. Luong, Chia Y. Lee, Ambrose L. Cheung
Rat/Mgra, A Regulator Of Autolysis, Is A Regulator Of Virulence Genes In Staphylococcus Aureus, Susham Ingavale, Willem Van Wamel, Thanh T. Luong, Chia Y. Lee, Ambrose L. Cheung
Dartmouth Scholarship
We have previously identified mgrA (rat) as a regulator of autolysis in Staphylococcus aureus. Besides its effect on autolytic activity, we recently found alterations in the expression of regulator and target virulence genes in the mgrA mutant. Northern analysis and transcription fusion assays showed that inactivation of mgrA has led to the downregulation of RNAIII of agr and hla and upregulation of sarS and spa. Although both SarA and agr are activators of α-hemolysin and a repressors of protein A synthesis, we found that the transcription of sarA was not affected in the mgrA mutant and …