Project description:The redox-sensing two-component signal transduction system, RegSR, in Rhodopseudomonas palustris has been shown to regulate an uptake hydrogenase in response to varying cellular redox states; however, its role is still largely undefined. Here, we used RNA sequencing to compare gene expression patterns in wild type R. palustris strain CGA010 to a ΔregSR derivative, CGA2023, under varying metabolic conditions. Growth conditions were chosen to utilize the different metabolic capabilites of R. palustris and, thus, present a variety of different redox challenges to the cell.
Project description:The global sanitary crisis derived from antibiotic multi-resistant bacteria entails the need to reduce sulfamethoxazole (SMX) concentrations in wastewater treatment plants (WWTPs). The key microorganisms and the biotransformation mechanisms leading to SMX removal remain incompletely characterized, particularly under aerobic heterotrophic conditions, which are becoming increasingly relevant in the design of novel, more energy-efficient, WWTPs. In this study, sequential batch reactors were inoculated with activated sludge, operated in heterotrophic conditions and spiked with six different initial SMX concentrations ranging between 0 and 2000 µg L-1. The goal was to determine the influence of SMX in the microbiome and its enzymatic expression through genomic, metaproteomic and transformation product analyses. The results allowed us to identify the metabolite 2,4(1H,3H)-pteridinedione-SMX (PtO-SMX), pointing to the role of the pterin-conjugation pathway in the biotransformation of SMX. Additionally, at increased SMX concentrations, through metaproteomics and 16S rRNA gene sequencing, it was determined a higher abundance of the genus Corynebacterium and a differential expression of five enzymes involved in its central metabolism, suggesting the relevant role of this bacteria to mitigate SMX risks.
2022-09-20 | PXD029711 | Pride
Project description:Algae stimulated coal microbial communities under different redox conditions
