Project description:In this study wild-type, fur mutant, and complemented fur mutant strains of the human pathogen Neisseria gonorrhoeae F62 were grown under high (100 uM iron) or low (100 uM desferal) iron conditions to identify genes whose expression was regulated by iron and/or Fur
Project description:In this study wild-type, fur mutant, and complemented fur mutant strains of the human pathogen Neisseria gonorrhoeae F62 were grown under high (100 uM iron) or low (100 uM desferal) iron conditions to identify genes whose expression was regulated by iron and/or Fur. This study looked at the response 3 hours after the addition of iron or desferal.
Project description:In Neisseria gonorrhoeae, Fur (ferric uptake regulator) protein regulates iron homeostasis gene expression through binding to conserved sequences in promoters of iron-responsive genes. We have expanded the gonococcal Fur regulon using a custom microarray to monitor iron-responsive gene expression throughout the growth curve combined with a genome-wide in silico analysis to predict Fur boxes (FB), and in vivo FuRTA assays to detect genes able to bind Fur. Keywords: time course: (1hr ,2hr, 3hr, 4hr)
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:Hfq is an RNA chaperone, which functions as a pleiotropic regulator for RNA metabolism in bacteria. To characterize the role of Hfq in pathogenicity of Neisseria gonorrhoeae we generated a N. gonorrhoeae hfq mutant, MS11hfq.Transcriptional analysis using a custom-made N. gonorrhoeae microarray revealed that 369 open reading frames were differentially regulated in MS11hfq compared to the wild-type (wt) strain (202 were upregulated, 167 were downregulated).
Project description:Neisseria gonorrhoeae, the etiologic agent of gonorrhea, is frequently asymptomatic in women, often leading to chronic infections. One factor contributing to this may be biofilm formation. N. gonorrhoeae can form biofilms over glass and plastic surfaces. There is also evidence that biofilm formation may occur during natural cervical infection. To further study the mechanism of this biofilm formation, transcriptional profiles of N. gonorrhoeae biofilm were compared to planktonic profiles. Biofilm RNA was extracted from N. gonorrhoeae 1291 grown for 48 hours in continuous flow chambers over glass. Planktonic RNA was extracted from the biofilm runoff. When biofilm was compared to planktonic growth, 3.8 % of the genome was differentially regulated. Genes highly up-regulated in biofilm included aniA, norB, and ccp, which play critical roles in anaerobic metabolism and oxidative stress tolerance. Down-regulated genes included the nuo gene cluster (NADH dehydrogenase) and the cytochrome bcI complex, which are involved in aerobic respiration and are thought to contribute to endogenous oxidative stress. Furthermore, we determined that aniA, ccp, and norB insertional mutants are attenuated for biofilm formation over glass and transformed human cervical epithelial cells (THCEC). This data suggests that biofilm formation could minimize oxidative stress during cervical infection and allow N. gonorrhoeae to maintain a nitric oxide steady state that may be anti-inflammatory.
Project description:Regulation of gene expression by small non-coding RNAs (sRNAs) plays a critical role in bacterial response to physiological stresses. NrrF, a trans-acting sRNA in Neisseria meningitidis and Neisseria gonorrhoeae, has been shown in the meningococcus to indirectly control, in response to iron (Fe) availability, the transcription of genes encoding subunits of succinate dehydrogenase, a Fe-requiring enzyme. Given that in other organisms sRNAs target multiple mRNAs to control gene expression, we used a global approach to examine the role of NrrF in controlling gonococcal transcription. Three strains, including N. gonorrhoeae FA1090, an nrrF deletion mutant and a complemented derivative were examined using a custom CombiMatrix microarray to assess the role of this sRNA in controlling gene expression in response to Fe availability. In the absence of NrrF, mRNA half-lives increased for 12 genes in Fe-depleted growth conditions, compared to FA1090. Biological functions for the 12 genes controlled by NrrF included energy metabolism, oxidative stress, antibiotic resistance, amino acid synthesis and a regulatory protein whose functions are not fully understood, in addition to hypothetical proteins.
Project description:Microarray comparative genome hybridization (mCGH) data was collected from one Neisseria cinerea, two Neisseria lactamica, two Neisseria gonorrhoeae, and 48 Neisseria meningitidis isolates. For N. meningitidis, these isolates are from diverse clonal complexes, invasive and carriage strains, and all major serogroups. The microarray platform represented N. meningitidis strains MC58, Z2491, and FAM18 and N. gonorrhoeae FA1090.
Project description:We assessed the small RNA transcriptome of Neisseria gonorrhoeae strain MS11 in two genetic backgrounds; using wild type cells as well as cells carrying a rppH insertional mutation. It was found that the presence of the RppH enzyme affected both the quantity and length of small RNAs in various chromosomal locations. However, in comparing the two transcriptomes, we found that not all small RNAs were differentially expressed, suggesting that RppH targets only a subset of transcripts.