Project description:RNA sequencing transcriptomics was performed on a highly multidrug resistant A. baumannii strain belonging to international clone I, AB5075_UW and a transposon insertion inactivated mutant of ABUW_0182 (acmS), which encodes a hybrid histidine kinase.Transcriptomics suggests that AcmS controls expression of the genes involved in short-chain fatty acid metabolism in A. baumannii. Biophysical analyses showed ABUW_0182 binds acetic and propionic acid with affinities in a low micromolar range, suggesting they represent the physiological ligands for this hybrid histidine kinase system.
Project description:In this study, we performed an RNA-Seq transcriptomic analysis concerning acetic acid bacteria’s acid resistance mechanisms during a continuous and periodical industrial submerged vinegar fermentation process, where the acetic acid concentration fluctuates between ~8% and ~12%
Project description:Two-stage two-phase biogas reactor systems consisting each of one batch downflow hydrolysis reactor (HR, vol. 10 L), one process fluid storage tank (vol. 10 L), and one downstream upflow anaerobic filter reactor (AF, vol. 10 L), were operated at mesophilic (M, 37 °C) and thermophilic (T, 55 °C) temperatures and over a period of > 750 d (Figure 1, Additional file 1). For each reactor system and for each process temperature, two replicates were conducted in parallel, denominated further as biological replicates. Further process details were as previously published. Start-up of all fermenters were performed using liquid fermenter material from a biogas plant converting cattle manure in co-digestion with grass and maize silage and other biomass at varying concentrations and at mesophilic temperatures. Silage of perennial ryegrass (Lolium perenne L.) was digested as sole substrate in batches of varying amounts with retention times of 28 d (storage of bale silage at -20 °C, cutting length 3 cm, volatile substances (VS) 32 % of fresh mass (FM), total Kjeldahl nitrogen 7.6 g kgFM-1, NH4+-N 0.7 g kgFM-1, acetic acid 2.6 g kgFM-1, propionic acid < 0.04 g kgFM-1, lactic acid 2.6 g kgFM-1, ethanol 2.2 g kgFM-1, C/N ratio 19.3, chemical oxygen demand (COD) 357.7 g kgFM-1, analysis of chemical properties according to [6]. No spoilage was observed in the silage. Biogas yields were calculated as liters normalized to 0 °C and 1013 hPa (LN) per kilogram volatile substances (kgVS). For chemical analysis, samples were taken from the effluents of HR and AF. For sequencing of 16S rRNA gene amplicon libraries, microbial metagenomes, and microbial metatranscriptomes, samples were taken from the silage digestate in the HR digested for 2 d. At this time point, high AD rates were detected as indicated by the fast increase of volatile fatty acids (VFA), e.g., acetic acid. Sampling was performed at two different organic loading rates (OLR), i.e., batch-fermentation of 500 g (denominated as “low OLR”, samples MOLR500 and TOLR500) and 1,500 g silage (denominated as “increased OLR”, samples MOLR1500 and TOLR1500).
Project description:P. bryantii B14 cells were cultivated separately in acetic (Acet), propionic (Prop), butyric (But), iso-butyric (iBut), valeric (Val), iso-valeric (iVal) and 2-methyl butyric acid (2MB) as well as in a mixture of all mentioned short-chain fatty acids (Mix). All 8 treatments were analyzed regarding their proteomes in order to understand the requirements and effects of each SCFA on the metabolism.
Project description:Comparing Arabidopsis plants gene expresion in normal conditions (control) with acetic acid treated plants (acetic). Plants were grown on liquid MS media for 13 days, then they were transfered to MS liquid media (control) or MS+3,5 acetic acid (acetic) for two hours.