Project description:Investigation of gene expression level changes in Gordonia sp. KTR9 upon exposure to RDX and Nitrogen Limitation, compared to controls with no RDX. The Gordonia sp. KTR9 strain used in this study has been previously described by Thompson KT, Crocker FH, Fredrickson HL.2005. Mineralization of the cyclic nitramine explosive hexahydro-1,3,5-trinitro-1,3,5-triazine by Gordonia and Williamsia spp. Appl Environ Microbiol. 2005 Dec;71(12):8265-72. A 12 x 135K array study using total RNA recovered from triplicate cultures of KTR9 exposed to RDX, triplicate cultures of KTR9 exposed to RDX and high nitrogen conditions, triplicate cultures of KTR9 exposed to low nitrogen, and triplicate cultures of controls exposed to high nitrogen.
Project description:Investigation of gene expression level changes in Gordonia sp. KTR9 upon exposure to RDX and Nitrogen Limitation, compared to controls with no RDX. The Gordonia sp. KTR9 strain used in this study has been previously described by Thompson KT, Crocker FH, Fredrickson HL.2005. Mineralization of the cyclic nitramine explosive hexahydro-1,3,5-trinitro-1,3,5-triazine by Gordonia and Williamsia spp. Appl Environ Microbiol. 2005 Dec;71(12):8265-72.
Project description:Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a persistent nitramine explosive with long-lasting properties. Rhodococcus sp. strain DN22 has been discovered as one of the microorganisms capable of RDX degradation. Despite respectable studies on Rhodococcus sp. strain DN22, the proteins participating in RDX degradation (Oxidoreductase and Cytochrome P450) in the strain remain to be fragments. In this study, complete genome of Rhodococcus sp. strain DN22 was sequenced and analyzed, and the entire sequences of the two genes encoding Oxidoreductase and Cytochrome P450 in Rhodococcus sp. strain DN22 were predicted, which were validated through proteomic data. Besides, despite the identification of certain chemical substances as proposed characterized degradation intermediates of RDX, few studies have investigated the physiological changes and metabolic pathways occurring within Rhodococcus sp. cells when treated with RDX, particularly through the use of mass spectrometry-based omics. Hence, proteomics and metabolomics of Rhodococcus sp. strain DN22 were performed and analyzed with the presence or absence of RDX in the medium. A total of 3186 protein groups were identified and quantified between the two groups, with 117 proteins being significantly differentially expressed proteins. A total of 1056 metabolites were identified after merging positive and negative ion modes, among which 131 metabolites were significantly differential. Through the combined analysis of differential proteomics and metabolomics, several KEGG pathways, including two-component system, ABC transporters, alanine, aspartate and glutamate metabolism, arginine biosynthesis, purine metabolism, nitrogen metabolism, and phosphotransferase system (PTS) were found to be significantly enriched. We expect that our investigation will expand the acquaintance of Rhodococcus sp. strain DN22, and the knowledge of microbial degradation.
Project description:Gene disruption of KTR9_0186 resulted in a 2-fold increase in TAG content in nitrogen starved cells. Lipase mutants subjected to carbon starvation, following nitrogen starvation, retained 75% more TAGs and retained pigmentation. Transcriptome expression data confirmed the deletion of KTR9_0186 and identified the up-regulation of key genes involved in fatty acid degradation, a likely compensatory mechanism for reduced TAG mobilization. The Gordonia sp. KTR9 strain used in this study has been previously described (PMID 16332812) A 12 x 135K array study using total RNA recovered from triplicate cultures of KTR9 under carbon starvation and triplicate cultures of KTR9 0186 Mutant under carbon starvation.
Project description:To further explore potential molecular mechanisms and pathways by which the presence or absence of the pGKT2 plasmid may be affecting the overall fitness cost in the native Gordonia sp KTR9 strain, transcriptome studies were performed. Transcriptome experiments comparing KTR9 wild-type and mutant strains grown in rich media confirmed the loss of the pGKT2 plasmid and also indicated the loss of the 90 kb pGKT1 plasmid.
Project description:Investigation of gene expression level changes in Gordonia sp. KTR9 and Gordonia sp. KTR9 mutant GlnR upon exposure to high and low nitrogen conditions The Gordonia sp. KTR9 strain used in this study has been previously described by Thompson KT, Crocker FH, Fredrickson HL.2005. Mineralization of the cyclic nitramine explosive hexahydro-1,3,5-trinitro-1,3,5-triazine by Gordonia and Williamsia spp. Appl Environ Microbiol. 2005 Dec;71(12):8265-72. A 12 x 135K array study using total RNA recovered from triplicate cultures of KTR9 exposed to high nitrogen conditions, triplicate cultures of KTR9 exposed to low nitrogen conditions, triplicate cultures of KTR9 mutant GlnR exposed to high nitrogen conditions, triplicate cultures of KTR9 mutant GlnR exposed to low nitrogen conditions.
