Project description:The overall goals and objectives of this study are to investigate the transcriptomics of Neisseria gonorrhoeae using RNA-seq. This work will look at gene expression, start points of transcription, transcriptional termination, and differences between these in different conditions and between strains and growing cultures over time.
Project description:Neisseria gonorrhoeae (NG) exhibits high genome plasticity caused by an unusually high density and diversity of transposable elements, and easily performs various mechanisms of drug resistance. Here we investigated the i19.05 clinical isolate with reduced susceptibility to penicillin (MIC=0.5 mg/L), tetracycline (MIC=0.5 mg/L), and azithromycin (MIC=1.0 mg/L), which carried no known genetic resistance determinants except of penA, which cannot explain the expression of the resistant phenotype. In addition, it attracted our attention to the presence of a new and unique mutation of Asn105Ser in SurA and several mutations in Omp85 (BamA). The goal of our study was to search for new molecular mechanisms of drug resistance. The pan susceptible n01.08 NG clinical isolate was involved as a control to compare, as well as a recipient in transformation procedure. The fragments of i19.05 genome contained mutant surA, omp85, and penA genes were amplified and used in spot-transformation of the n01.08 recipient isolate as described (Ilina, 2013). Finally, a resistant transformant NG05 (PenAmut, Ompmut, SurAmut) was obtained. For comprehensive proteomic analysis via LC-MS/MS, the proteins from the all tested N. gonorrhoeae strains were fractionated on cell envelope (CE) (including outer membrane, periplasmic, inner membrane) and cytosol (C). A total of 1125 proteins in the CE fraction, of which 894 were common in all strains were identified. Proteomics of the C fraction in the same experiment yielded a total of 928 proteins, of which 676 were shared among all strains. Proteome coverage for both fractions ranged from 52.72% (1111 proteins) in n01.08 to 54.53% (1149 proteins) in i19.05.
Project description:Transcriptional profiling of N. gonorrhoeae comparing wild type cells to cells with inactivated by chloramphenicol cassette (cm) dam replacing gene (drg) or wild type cells comparing to cells with inserted dam gene. The Goal was to study the role of drg or dam presence in overall expression profile.
Project description:Naturally occurring mtrR mutants of gonococci displaying clinically relevant levels of antibiotic resistance are often isolated from patients and mtrR mutants have been reported to be more fit than the wild type parent strain in a murine vaginal infection model. DNA-binding proteins, such as MtrR, that negatively regulate bacterial efflux pump genes have been considered to be “local” gene regulators, although there is increasing evidence that they can directly or indirectly influence expression of other genes. To define the regulatory properties of MtrR we employed microarray analysis of isogenic MtrR-positive and MtrR-negative gonococci. Keywords: single time point