Project description:In previous work in our group, shotgun genome sequencing of Arthrobacter sp. revealed potential new P450 monooxygenases and many other oxidoreductases with putative hydroxylation activity. A targeted approach to identify enzymes involved in the degradation of certain molecules is proteomic analysis. In the case of growth on certain substances, enzymes like P450s, which are responsible for the observed organism’s capabilities, might be overexpressed or initially induced.
Project description:Arthrobacter chlorophenolicus A6 is a 4-chlorophenol degrading soil bacterium with high phyllosphere colonization capacity. Till now the genetic basis for the phyllosphere competency of Arthrobacter or other pollutant-degrading bacteria is uncertain. We investigated global gene expression profile of A. chlorophenolicus grown in the phyllosphere of common bean (Phaseolus vulgaris) compared to growth on agar surfaces.
Project description:Arthrobacter chlorophenolicus A6 is a 4-chlorophenol degrading soil bacterium with high phyllosphere colonization capacity. Till now the genetic basis for the phyllosphere competency of Arthrobacter or other pollutant-degrading bacteria is uncertain. We investigated global gene expression profile of A. chlorophenolicus grown in the phyllosphere of common bean (Phaseolus vulgaris) compared to growth on agar surfaces. We designed transcriptome arrays and investigated which genes had different transcript levels in the phyllosphere of common bean (Phaseolus vulgaris) as compared to agar surfaces. Since water availability is considered an important factor in phyllosphere survival and activity, we included both high and low relative humidity treatments for the phyllosphere-grown cells. In addition, we determined the expression profile under pollutant exposure by the inclusion of two agar surface treatments, i.e. with and without 4-chlorophenol.
Project description:This study assess the biocompatibility of Ti-26Nb compared to Ti-Cp, a reference in implantology, through the combination of conventional toxicological assay, morphological observations and transcriptomic analysis performed on two different cells line : Saos-2 and THP-1. The biocompatibility of Ti-Cp implants was evaluated in comparison with Ti-26Nb implants both having a mirror polished surface, studying cell proliferation (trypan blue and WST-1) and cell morphology/adhesion (SEM) on human THP-1 and Saos-2 cell lines. Finally, an evaluation of a potential toxicity of potassium niobiate powder KNbO3 was carried out by measuring metabolic activity and realizing a transcriptomic study on the THP-1 line (the first one) to deepen the results observed with Ti-26Nb discs. Indeed, niobiate ions are potentially released from implant in cellular acidic environnement. Concerning Saos-2 cells, our results suggest that Ti-26Nb and Ti-Cp discs do not impact proliferation and viability. Concerning THP-1 cell line, a decrease in proliferation and viability is observed in contact of Ti-26Nb discs (hypothesis of a cell-line effect ?, no biocompatibility study on monocyte/macrophage cell lines such as THP-1 actually available in literature). KNbO3 powder does not impact viability of THP-1 cells and does not induce changes at molecular level. Taken together, these data suggest a possible toxicity of Ti-26Nb toward THP-1 cells not directly related to the niobium but perhaps to the manufacturing process of Titane niobium alloy.
Project description:Arthrobacter sp. CGMCC 3584 are able to produce high yields of extracellular cyclic adenosine monophosphate (cAMP), which plays a vital role in the field of treatment of disease and animal food, during aerobic fermentation. DNA array-based transcriptional analysis of Arthrobacter cells was conducted to elucidate the higher productivity of cAMP under high oxygen supply. Results showed that 14.1% and 19.3% of the whole genome genes were up-regulated and down-regulated notably, respectively. The largest group with altered transcriptional levels belonged to the group involved in carbohydrate transport and metabolism. Other large functional groups of differentially expressed genes changed significantly included amino acid transport and metabolism, inorganic ion transport and metabolism and transcription.
Project description:We have employed circRNAs, miRNAs and mRNAs expression profiling as a discovery platform to identify genes with the potential to distinguish rBMSCs affected by Ta-modified Ti surface or simple Ti surface