Project description:Competition between bacteria can impact the ability to colonize a host. In the accessory nidamental gland (ANG) reproductive symbiosis of the Hawaiian bobtail squid, Euprymna scolopes, symbionts colonize various epithelium lined tubules of adult females. We hypothesize that symbionts may use competitive mechanisms to determine ANG tubule colonization outcomes. One ANG strain, Leisingera sp. ANG-M7, was found to inhibit another ANG symbiont, Leisingera sp. ANG-DT, in vitro. Transposon mutagenesis was used to determine the genes required for this antimicrobial activity. Seven ANG-M7 transposon mutants were found with significantly decreased ability to inhibit ANG-DT compared to WT ANG-M7. Of these mutants, three strains (P08F1, P24E3, P40B12) were selected for transcriptome sequencing to look for shared pathways that were significantly different from WT.
Project description:Angiotensin II (Ang II)-mediated vascular smooth muscle cells (VSMC) dysfunction plays a critical role in cardiovascular diseases. However, the gene expression in this process is unclear. We used Rat Affymetrix gene array to profile Ang II-regulated gene in RVSMC and evaluated their role in VSMC dysfunction. Examined 4 samples of Rat VSMC in triplicate. Control (without Ang II treatment) and 3 samples treated with Ang II for 6h, 12h, and 24h. Compared the changes in gene expression in Ang II treated samples relative to control samples.
Project description:Stress response of Methylococcus capsulatus str.Bath toward hydrogen sulfide (H2S) was investigated via physiological study and transcriptomic profiling. M. capsulatus (Bath) can grow and tolerate up to 0.75%vol H2S in headspace. Vast change in pH suggests biological relevant sulfide oxidation. Dozens of H2S-sensitive genes were identified from comparison of cell transcriptome in different H2S concentrations. Mc sulfide quinone reductase (SQR) and persulfide dioxygenase were found to be active during sulfide detoxification. Moreover, xoxF, a novel lanthanide(Ln)-dependent methanol dehydrogenase (MDH) was overexpressed in H2S while mxaF, a calcium-dependent MDH, was down-regulated, and such MDH switch phenomenon is also well known to be induced by addition of lanthanide via an as-yet-unknown mechanism. Activities in quorum sensing and RND efflux pump also suggest their role in sulfide detoxification, and might provide insight on the xoxF/mxaF switch mechanism.
