Project description:Hexavalent chromium (Cr(VI)) is a highly toxic contaminant, some bacteria are able to transform it to less toxic and less soluble trivalent chromium (Cr(III)). Klebsiella sp. strain AqSCr, isolated from Cr(VI)-polluted groundwater, reduces Cr(VI) both aerobically and anaerobically, and resists up 35 mM of Cr(VI); Subculturing of AqSCr in the presence of Cr(VI) conduces to adaptation. In this study, we performed RNA-Seq of Cr(VI) adapted stage, finding 255 genes upregulated and 240 downregulated with respect to controls without Cr(VI). Genes differentially expressed are mostly associated with oxidative stress response, DNA repair and replication, sulfur starvation response, envelope-osmotic stress response, fatty acid metabolism, ribosomal subunits and energy metabolism. Among them, genes not previously associated with chromium resistance as cybB, encoding a putative superoxide oxidase, gltA2, encoding an alternative citrate synthase, and des, encoding a fatty acid desaturase were upregulated. The alternative sigma factors fecl, rpoE and rpoS were upredgulated in Cr(VI) adapted cells, then they participate in orchestate the Cr(VI)-resistance mechanisms in AqSCr strain

2021-05-20 | GSE160968 | GEO

bioreactor sludge metagenome

Project description:Anaerobically digestion sludge Metagenome

| PRJNA255709 | ENA

Metagenome of a digested sewage sludge-derived enrichment culture

Project description:Metagenome of a digested sewage sludge-derived enrichment culture Raw sequence reads

| PRJNA530715 | ENA

S. oneidensis MR-1 with electrode, Fe(III)citrate and oxygen as electron acceptor

Project description:S. oneidensis MR-1 was grown with different electron acceptors: an electrode at 0.4 V vs. SHE, 50 mM Fe(III)citrate, and oxygen. The gene expression pattern for each experiment was analyzed and the differences in gene expression for the different experimental conditions were compared. For two samples S. oneidensis was grown with a graphite anode electrode (at 0.4 V. vs. SHE) as the only electron acceptor - one sample was directly fed with 20 mM lactate, one sample was fed with lactate produced during fermentation of glucose by Lactococcus lactis. Four samples were grown anaerobically with 50 mM Fe(III)citrate as the only electron acceptor, and 20 mM lactate for 20 h. Three samples were grown aerobically with 20 mM lactate for 20 h. The same modified M4 medium was used for all samples. For RNA extraction, the biofilm was scraped off the frozen (-80M-BM-0C) carbon electrode with a sterile razor blade. Biofilm-carbon sludge was combined with 7 mL ice-cold phosphate buffer saline (PBS), vortexed, sonicated at 7 W for 30 s on ice (3 repetitions), and centrifuged. For the liquid cultures, 2 mL of each culture were combined with 2 mL RNA protect, vortexed, and centrifuged at 5,500g for 10 min. The pellets were resuspended in NAES buffer (50 mM sodium acetate buffer, 10 mM EDTA and 1 % SDS at pH 5). RNA was isolated with a phenol:chloroform extraction protocol.

2011-02-01 | E-GEOD-20379 | biostudies-arrayexpress

sludge metagenome

Project description:sludge (excess sludge primary sludge digested sludge) Raw sequence reads

| PRJNA429689 | ENA