Project description:A significant part of the heavier petroleum fraction resulting from offshore oil-spills sinks to the deep-sea. Its fate and biodegradation by microbial communities is unclear. In particular, the physiological and metabolic features of hydrostatic pressure (HP) adapted oil-degraders have been neglected. In this study, hydrocarbon-free sediment from 1km below surface water (bsl) was incubated at 0.1, 10 and 20MPa (equivalent to surface waters, 1 and 2km bsl) using triacontane (C30) as sole carbon source for a 3-month enrichment period. HP strongly impacted biodegration, as it selected for microbial communities with small cells, high O2 respiration and nutrients requirements, but low biomass and C30-degradation yields. The alkane-degrading metaproteome linked to β-oxidation was detected but its expression was reduced under HP contrary to several housekeeping genes. This was reflected in the enriched communities, as atmospheric pressure was dominated by hydrocarbonoclastic bacteria while non-specialized or previously unrecognized oil-degrading genera were enriched under HP.
Project description:Hydrostatic pressure is one of the main mechanical stimuli cartilage cells are submitted to during joint loading. If moderate hydrostatic pressure is known to be beneficial to cartilage differentiation, excessive pressure, on the other hand, induces changes in cartilage similar to those observed in osteoarthritic cartilage. Therefore, the purpose of the experiment is to identify new target genes of high hydrostatic pressure in chondrocyte precursor cells.
Project description:This SuperSeries is composed of the following subset Series: GSE28410: Mouse oocytes: High hydrostatic pressure (HP) treated vs. Control GSE28411: Mouse in vitro fertilized four-cell stage embryos: High hydrostatic pressure (HP) treated vs. Control Refer to individual Series
Project description:Pseudothermotoga elfii strain DSM9442 and P. elfii subsp. lettingae strain TMOT are hyperthermophilic bacteria. P. elfii is a moderate piezophile, isolated from an oil-producing well in Africa at a depth of more than 1600 m. P. lettingae is piezotolerant, isolated from a thermophilic bioreactor fed with methanol as the sole carbon and energy source. In this study, we analysed these bacteria at the genomic and transcriptomic levels. According to the hydrostatic pressure growth conditions the transcriptomic analyses revealed differentially expressed genes emphasizing amino acid and sugars metabolism and transport as the major hydrostatic pressure responding processes. Notably, this work highlights the central role of the amino acid aspartate as key intermediate of the pressure adaptation mechanisms of the deep strain P. elfii DSM 9442. In addition, several differentially expressed genes involved in the membrane and cell wall biosynthesis pathways may be linked to the chain formation morphotype previously described at high pressure for strain P. elfii DSM9442.
Project description:Hydrostatic pressure is one of the physical factors affecting cellular physiology. Hydrostatic pressure of a few hundred MPa decreases the viability of yeast cells, and pressure of a few tens MPa decreases the growth rate. To understand the effect of hydrostatic pressure, we employed yeast, Saccharomyces cerevisiae, DNA microarrays and analyzed genome-wide mRNA expression profiles under hydrostatic pressures. In this experiment, we selected a hydrostatic pressure of 30 MPa at 25 degrees C because yeast cells are able to grow with this condition. Keywords: stress response
Project description:Hydrostatic pressure is one of the physical factors affecting cellular physiology. Hydrostatic pressure of a few hundred MPa decreases the viability of yeast cells, and pressure of a few tens MPa decreases the growth rate. To understand the effect of hydrostatic pressure, we employed yeast, Saccharomyces cerevisiae, DNA microarrays and analyzed genome-wide mRNA expression profiles under hydrostatic pressures. In this experiment, we selected a hydrostatic pressure of 40 MPa at 25 degrees C because the condition is not lethal for yeast cells but the growth was suppressed. Keywords: stress response
Project description:Series containes 4 independent experiments and high and low power scanns for each independent experiment. Genome-wide mRNA expression profiles of Saccharomyces cerevisiae growing under hydrostatic pressure were characterized. We selected a hydrostatic pressure of 30 MPa at 25°C because yeast cells were able to grow under these conditions, while cell size and complexity were increased after decompression. Functional characterization of pressure-induced genes suggests that genes involved in protein metabolism and membrane metabolism were induced. The response to 30 MPa was significantly different from that observed under lethal conditions because protein degradation was not activated under 30 MPa pressure. Strongly induced genes included those that contribute to membrane metabolism and which are also induced by detergents, oils, and membrane stabilizers.
Project description:We investigated a contaminant-degrading microbial community by sequencing total RNA (without rRNA depletion) from microcosms containing sediment from a hypoxic contaminated aquifer fed with isotopically labeled toluene.
Project description:Chondrocytes are subject to continuous loads placed upon them throughout development and physical activity. Normal physiological loads enable the maintenance of the articular cartilage health, however abnormal loads contribute to pathological joint ageing. Similarly, the growth plate cartilage is exposed to a number of loads during growth and development. Due to the high-water content of cartilage, hydrostatic pressure is considered one of the main biomechanical influences on chondrocytes and it plays an important role in the mechanoregulation of cartilage. Therefore in this study we conducted RNA-seq analysis of ex vivo hip cap (articular) and metatarsal (growth) cartilage cultures after physiological and injurious hydrostatic pressure. Gene expression in response to 5mPa (physiological) or 50mPa (injurious) hydrostatic pressure was quantified by transcriptome analysis using the Illumina platform