Project description:This SuperSeries is composed of the following subset Series: GSE5268: Effects of biphenyl on Rhodococcus sp. RHA1 GSE5269: Effects of ethylbenzene on Rhodococcus sp. RHA1 GSE5270: Effects of benzoate on Rhodococcus sp. RHA1 Refer to individual Series
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:Study of the potential of Antarctic microorganisms for use in bioremediation is of increasing interest due to their adaptations to harsh environmental conditions and their metabolic potential in removing a wide variety of organic pollutants at low temperature. In this study, the psychrotolerant bacterium Rhodococcus sp. strain AQ5-07, originally isolated from soil from King George Island (South Shetland Islands, maritime Antarctic), was found to be capable of utilizing phenol as sole carbon and energy source. The bacterium achieved 92.91% degradation of 0.5 g/L phenol under conditions predicted by response surface methodology (RSM) within 84 h at 14.8 °C, pH 7.05, and 0.41 g/L ammonium sulphate. The assembled draft genome sequence (6.75 Mbp) of strain AQ5-07 was obtained through whole genome sequencing (WGS) using the Illumina Hiseq platform. The genome analysis identified a complete gene cluster containing catA, catB, catC, catR, pheR, pheA2, and pheA1. The genome harbours the complete enzyme systems required for phenol and catechol degradation while suggesting phenol degradation occurs via the β-ketoadipate pathway. Enzymatic assay using cell-free crude extract revealed catechol 1,2-dioxygenase activity while no catechol 2,3-dioxygenase activity was detected, supporting this suggestion. The genomic sequence data provide information on gene candidates responsible for phenol and catechol degradation by indigenous Antarctic bacteria and contribute to knowledge of microbial aromatic metabolism and genetic biodiversity in Antarctica.