Project description:Analysis of Pseudomonas aeruginosa PAO1 (ATCC 15692) transcriptional response by disruption of oxyR. PAO1 cells are evaluated with RNA-seq to understand the genes affected by this mutation. Our results provide new vision on the regulation of oxyR in pathogens.
Project description:Oxidative stress caused by exposure to reactive oxygen species (ROS), is a major challenge for aerobic and especially anaerobic organisms. Bacteria coordinate the response to oxidative stress through the LysR-type transcriptional regulator (LTTR) OxyR. Extensive studies have focused on the classical Escherichia coli system to shed light on the mode of action of defensive weapons against oxidative stress. The underlying mechanism is mediated via the formation of redox-dependent disulfide bond between two conserved cysteines of OxyR, thus activating transcription of members of the OxyR regulon. However, only fragmentary information on the regulation and function of OxyR has been gleaned through genetic and biochemical analyses in the important opportunistic pathogen P. aeruginosa. In this report, we used a comprehensive transcriptional profiling analysis to delineate the OxyR regulon under three conditions (KingM-bM-^@M-^Ys A medium [Pseudomonas medium or PM], Luria Broth (LB), and LB when oxyR is overexpressed), to investigate its roles in different cellular aspects that are independent of the classical oxidative stress response. Interestingly, when grown in LB, OxyR was found to regulating many genes involved in the process of inter-cellular communication known as quorum sensing (QS). In contrast, when grown in PM, OxyR regulate the expression of a newly identified CSS (cell-surface signaling) system in an OxyR-dependent fashion. In addition, the results from oxyR overexpression further confirmed that OxyR was linked to regulation of QS and Type 3 Secretion (T3SS) in addition to the regulation of antioxidative genes. Taken together, our results show that, apart from its dominant role in defense against oxidative stress in P. aeruginosa, OxyR acts as a global regulator that provides a link between the regulation of oxidative stress response, QS and virulence. 15 samples, representing 5 different biological conditions, including 3 biological replicates for each condition
Project description:Oxidative stress caused by exposure to reactive oxygen species (ROS), is a major challenge for aerobic and especially anaerobic organisms. Bacteria coordinate the response to oxidative stress through the LysR-type transcriptional regulator (LTTR) OxyR. Extensive studies have focused on the classical Escherichia coli system to shed light on the mode of action of defensive weapons against oxidative stress. The underlying mechanism is mediated via the formation of redox-dependent disulfide bond between two conserved cysteines of OxyR, thus activating transcription of members of the OxyR regulon. However, only fragmentary information on the regulation and function of OxyR has been gleaned through genetic and biochemical analyses in the important opportunistic pathogen P. aeruginosa. In this report, we used a comprehensive transcriptional profiling analysis to delineate the OxyR regulon under three conditions (King’s A medium [Pseudomonas medium or PM], Luria Broth (LB), and LB when oxyR is overexpressed), to investigate its roles in different cellular aspects that are independent of the classical oxidative stress response. Interestingly, when grown in LB, OxyR was found to regulating many genes involved in the process of inter-cellular communication known as quorum sensing (QS). In contrast, when grown in PM, OxyR regulate the expression of a newly identified CSS (cell-surface signaling) system in an OxyR-dependent fashion. In addition, the results from oxyR overexpression further confirmed that OxyR was linked to regulation of QS and Type 3 Secretion (T3SS) in addition to the regulation of antioxidative genes. Taken together, our results show that, apart from its dominant role in defense against oxidative stress in P. aeruginosa, OxyR acts as a global regulator that provides a link between the regulation of oxidative stress response, QS and virulence.
Project description:Analysis of Pseudomonas aeruginosa PAO1 (ATCC 15692) treated by Tanreqing. PAO1 cells are evaluated with RNA-seq to understand the genes affected by this antibacterial agent. Our results provide new vision on the mode of action by Tanreqing.
Project description:Oxidative stress that originates from reactive oxygen species (ROS) is an inevitable consequence of aerobic respiration in bacteria. Three transcription factors (TFs), OxyR, SoxR, and SoxS play a critical role in transcriptional regulation of the defense system. However, the full genome-wide regulatory potential of them remains elusive. Here, we comprehensively reconstruct genome-wide OxyR, SoxR, and SoxS transcriptional regulatory networks in Escherichia coli under oxidative stress. Integrative data analysis reveals that OxyR, SoxR, and SoxS regulons are comprised of 38 genes in 28 transcription units (TUs), 11 genes in 10 TUs, and 34 genes in 25 TUs, respectively, significantly expanding the current knowledge of their regulatory networks. Comparison of them to other stress-response regulatory networks highlights minimal overlap between their regulons, indicating that E. coli has a series of relatively distinct stress responses covering the range of different stresses. We also demonstrate that these intricate networks coordinate detoxification process with DNA and protein damage repair, cell wall synthesis, divalent metal ion homeostasis, as well as metabolic robustness to produce overall response of E. coli to oxidative stress. A total of six samples were analyzed. oxyR-8myc, soxR-8myc, and soxS-8myc tagged cells were cultured in M9 minimal media with 0.2% glucose. Then cells were treated with 250 uM of paraquat at mid-log pahse for 20 min with agitation.
Project description:Oxidative stress that originates from reactive oxygen species (ROS) is an inevitable consequence of aerobic respiration in bacteria. Three transcription factors (TFs), OxyR, SoxR, and SoxS play a critical role in transcriptional regulation of the defense system. However, the full genome-wide regulatory potential of them remains elusive. Here, we comprehensively reconstruct genome-wide OxyR, SoxR, and SoxS transcriptional regulatory networks in Escherichia coli under oxidative stress. Integrative data analysis reveals that OxyR, SoxR, and SoxS regulons are comprised of 38 genes in 28 transcription units (TUs), 11 genes in 10 TUs, and 34 genes in 25 TUs, respectively, significantly expanding the current knowledge of their regulatory networks. Comparison of them to other stress-response regulatory networks highlights minimal overlap between their regulons, indicating that E. coli has a series of relatively distinct stress responses covering the range of different stresses. We also demonstrate that these intricate networks coordinate detoxification process with DNA and protein damage repair, cell wall synthesis, divalent metal ion homeostasis, as well as metabolic robustness to produce overall response of E. coli to oxidative stress.
Project description:Oxidative stress that originates from reactive oxygen species (ROS) is an inevitable consequence of aerobic respiration in bacteria. Three transcription factors (TFs), OxyR, SoxR, and SoxS play a critical role in transcriptional regulation of the defense system. However, the full genome-wide regulatory potential of them remains elusive. Here, we comprehensively reconstruct genome-wide OxyR, SoxR, and SoxS transcriptional regulatory networks in Escherichia coli under oxidative stress. Integrative data analysis reveals that OxyR, SoxR, and SoxS regulons are comprised of 38 genes in 28 transcription units (TUs), 11 genes in 10 TUs, and 34 genes in 25 TUs, respectively, significantly expanding the current knowledge of their regulatory networks. Comparison of them to other stress-response regulatory networks highlights minimal overlap between their regulons, indicating that E. coli has a series of relatively distinct stress responses covering the range of different stresses. We also demonstrate that these intricate networks coordinate detoxification process with DNA and protein damage repair, cell wall synthesis, divalent metal ion homeostasis, as well as metabolic robustness to produce overall response of E. coli to oxidative stress.
Project description:Oxidative stress that originates from reactive oxygen species (ROS) is an inevitable consequence of aerobic respiration in bacteria. Three transcription factors (TFs), OxyR, SoxR, and SoxS play a critical role in transcriptional regulation of the defense system. However, the full genome-wide regulatory potential of them remains elusive. Here, we comprehensively reconstruct genome-wide OxyR, SoxR, and SoxS transcriptional regulatory networks in Escherichia coli under oxidative stress. Integrative data analysis reveals that OxyR, SoxR, and SoxS regulons are comprised of 38 genes in 28 transcription units (TUs), 11 genes in 10 TUs, and 34 genes in 25 TUs, respectively, significantly expanding the current knowledge of their regulatory networks. Comparison of them to other stress-response regulatory networks highlights minimal overlap between their regulons, indicating that E. coli has a series of relatively distinct stress responses covering the range of different stresses. We also demonstrate that these intricate networks coordinate detoxification process with DNA and protein damage repair, cell wall synthesis, divalent metal ion homeostasis, as well as metabolic robustness to produce overall response of E. coli to oxidative stress. A total of eight samples were analyzed. WT, ΔoxyR, ΔsoxR, and ΔsoxS mutant cells were cultured in M9 minimal media with 0.2% glucose. Then cells were treated with 250 uM of paraquat at mid-log pahse for 20 min with agitation.