Project description:Two parallel anaerobic digestion lines were designed to match a "bovid-like" digestive structure. Each of the lines consisted of two Continuous Stirred Tank Reactors placed in series and separated by an acidic treatment step. The first line was inoculated with industrial inocula whereas the second was seeded with cow digestive tract contents. After three month of continuous sewage sludge feeding, samples were recovered for shotgun metaproteomic and DNA-based analysis. Strikingly, protein inferred and 16S rDNA tags based taxonomic community profiles were not fully consistent. Principal Component analysis however revealed a similar clustering pattern of the samples, suggesting that reproducible methodological and/or biological factors underlie this observation. The performances of the two digestion lines did not differ significantly and the cow derived inocula did not establish in the reactors. A low throughput metagenomic dataset (3.4x106 reads, 1.1 Gb) was also generated for one of the samples. It allowed a substantial increase of the analysis depth (increase of the spectral identification rate). For the first time, a high level of proteins expressed by members of the "Candidatus Competibacter" group is reported in an anaerobic digester, a key microbial player in environmental bioprocess communities.
2015-08-12 | PXD002420 | Pride
Project description:In-situ biogas upgrading in mesophilic and thermophilic continuous stirred tank reactors
| PRJNA422355 | ENA
Project description:Hydrogen production in continuous tubular reactors
Project description:Development of microtiter plate based microbioreactor cultivation for Aspergillus giganteus with quasi-continuous online measurements. Different parameters such as well geometry, shaking frequency and morphology controlling agents were investigated in order to optimize the microtiter plate cultivation and scattered light signal towards reproducibility and homogeneity. An optimized medium was developed and scalability into stirred tank bioreactor cultivation was analyzed. As a transferability indicator the supernatant of both cultivation systems was analyzed for secreted protein patterns with a focus on an antifungal protein (AFP) and alpha-sarcin. These proteins were identified via LC-MS/MS.
Project description:Comparison of gene expression profile of human pluripotent stem cells (hHSC_F1285T_iPS2) expanded in perfused stirred tank bioreactors after 3 and 7 days compared to 2D precultures (day 0)
Project description:Corynebacterium glutamicum is well-known as an industrial workhorse, most notably for its use in the bulk production of amino acids in the feed and food sector. Fast growth and robustness against oscillatory oxygen availability, which can occur in large-scale bioreactors, are advantageous properties of this bacterium. However, previous studies of the effect of gradients in scale-down reactors with complex media disclosed an accumulation of several carboxylic acids and a parallel decrease of growth and product accumulation by C. glutamicum. This study addresses the impact of carboxylic acids, e.g. acetate and L-lactate, on the cultivation process and their potential role in scale up related performance losses. In order to mimic a discontinuous oxygen supply, a fluctuating power input in shake flask and stirred tank cultivations with mineral salt was applied. One focus of this study is to identify relative changes in the proteome due to the differing availability of carboxylic acids under discontinuous oxygen supply.
Project description:In large-scale production processes, metabolic control is typically achieved by limited supply of essential nutrients like ammonia. With increasing bioreactor dimensions, microbial producers such as Escherichia coli are exposed to changing substrate availabilities due to limited mixing. In turn, cells sense and respond to these dynamic conditions leading to frequent activation of their regulatory programs which result in production yield losses. This study is focused on transcriptional changes due to fluctuating ammonia supply, while sampling a continuously running two-compartment bioreactor system comprising a stirred tank reactor (STR) and a plug flow reactor (PFR). A previously created mutant E.coli SR was used to limit the reaction to environmntal influences via knock-out of stringent response. E. coli WT revealed highly diverging short-term transcriptional responses in ammonia fluctuation compared E. coli SR.