Project description:mRNA levels were measured in Rhodobacter sphaeroides 2.4.1 at 20% O2 and 0.5% O2, Rhodobacter sphaeroides 2.4.1 App11 (AppA-null), Rhodobacter sphaeroides 2.4.1 (pPNs) and PpsR mutant PPS2-4. The mRNA samples were prepared from cultures supplied with 20% O2, 1% CO2, and 79% N2, and grown in the dark to an OD of 0.18. The mRNA levels for each strain was measured three times. Keywords: repeat sample
Project description:Cyanobacteria Prochlorococcus marinus subsp. pastoris str. CCMP1986 (MED4) and Prochlorococcus marinus str. MIT 9313 (MIT9313) are oceanic oxygenic phototrophs, where MED4 is abundant in surface waters (~0-50 meters) and MIT9313 is abundant at depths of ~100 meters. To explore nitrogen-regulated changes in gene expression in these Prochlorococcus ecotypes, log phase cultures of MED4 and MIT9313 were transferred to either nitrogen-replete (800 uM ammonium) or medium lacking supplemental nitrogen. Samples were taken over a time series in order to characterize changes in physiology and gene expression during increasing nitrogen starvation. The two ecotypes' molecular responses to different nitrogen sources were also assessed by comparing gene expression of log phase cultures growing in ammonium vs. urea and cyanate (MED4), and vs. urea and nitrite (MIT9313).
Project description:This SuperSeries is composed of the following subset Series: GSE39711: RpoHI and RpoHII regulons in Rhodobacter sphaeroides 2.4.1 from chromatin immuno-precipitation GSE39712: RpoHI and RpoHII regulons in Rhodobacter sphaeroides 2.4.1 from gene expression profiling Refer to individual Series
Project description:Rhodobacter sphaeroides 2.4.1 illuminated with either lumiline bulbs at 10W/m2 or tungsten bulbs at 100W/m2. Sparged with 95%N/5%CO2. Keywords: other
Project description:DNA microarray analysis was employed to investigate the transcriptome response to nitrosative stress in a non-denitrifying facultative photosynthetic bacterium Rhodobacter sphaeroides 2.4.1. We focused on the role played by a nitric oxide-response transcriptional regulator NnrR in the response. The transcriptome profiles of R. sphaeroides 2.4.1 and its nnrR mutant before and after exposure to nitrosating agents S-nitrosoglutathione (GSNO) or sodium nitroprusside (SNP) under semiaerobic conditions were analyzed.
Project description:The facultatively photosynthetic bacterium Rhodobacter sphaeroides harbors an unusual LOV (light, oxygen, voltage) domain protein, RsLOV. While showing a characteristic photocycle, the protein misses a C - terminal output domain, similar to PpSB2 in Pseudomonas putida. Oxygen tension and light quantity are the two main responsible factors controlling the expression of photosynthesis genes in Rhodobacter sphaeroides. Two photoreceptor proteins are known to be involved in this regulation: the intensively studied AppA protein and the more recently identified cryptochrome-like protein CryB. Here we show by transcriptome and physiological studies that RsLOV is also involved in the regulation of photosynthetic gene expression. Our data further hint to a connection between RsLOV and the carbon hydrate metabolism, chemotaxis, as well as to the cellular response to photooxidative stress. RsLOV does not only affect blue light dependent gene expression but also redox-dependent regulation. This SuperSeries is composed of the following subset Series: GSE33194: R. sphaeroides ?lov vs. R. sphaeroides 2.4.1 (microarobic conditions) GSE33259: R. sphaeroides ?lov vs. R. sphaeroides 2.4.1 (blue light, semiaerobic conditions) GSE33260: R. sphaeroides ?lov vs. R. sphaeroides 2.4.1 (singlet oxygen stress, aerobic conditions)
Project description:DNA microarray analysis was employed to investigate the transcriptome response to nitrosative stress in a non-denitrifying facultative photosynthetic bacterium Rhodobacter sphaeroides 2.4.1. We focused on the role played by a nitric oxide-response transcriptional regulator NnrR in the response. The transcriptome profiles of R. sphaeroides 2.4.1 and its nnrR mutant before and after exposure to nitrosating agents S-nitrosoglutathione (GSNO) or sodium nitroprusside (SNP) under semiaerobic conditions were analyzed. R. sphaeroides 2.4.1 and its nnrR mutant were cultivated in glass bottles under semiaerobic growth conditions. When the optical density at 600 nm reached approximately 0.15-0.2, 1 mM GSNO or SNP was added to the medium. RNA was isolated from a 50 ml aliquot of the culture prior to the addition of GSNO or SNP and at 15 min after the addition. The experiment was performed in duplicate independent cultures.
