Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

A transcriptional study of acidogenic chemostat cells of Clostridium acetobutylicum - cellular behavior in adaptation to n-butanol

ABSTRACT: Clostridium acetobutylicum is well-known for its butanol production. Butanol toxicity is a major drawback for the generation of high-butanol producing strains. Here, the transcriptional response a steady state, acidogenic (pH 6), phosphate-limited Clostridium acetobutylicum chemostat culture to different levels of n-butanol (0.25-1%) was investigated. For the butanol challenge experiments butanol (1-butanol) was added (a) to the supplying medium and (b) to the culture vessel to guarantee an immediate change in the butanol concentration. Addition of butanol to the culture was timed to match the supply of the new medium through the feedlines. The butanol concentration was increased stepwise in intervals of 66.6 h (5 volume changes) to moderate butanol concentrations of 0.25%, 0.5%, 0.75% and 1% (v/v).

ORGANISM(S): Clostridium acetobutylicum

SUBMITTER: Katrin Schwarz

PROVIDER: E-MEXP-3571 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Similar Datasets

Project description:The presence of anti-microbial phenolic compounds, such as the model compound ferulic acid, in biomass hydrolysates poses significant challenges to the widespread use of biomass in conjunction with whole cell biocatalysis or fermentation. Biofuel toxicity must also be overcome to allow for efficient production of next generation biofuels such as butanol, isopropanol, and others for widespread usage. Currently, these inhibitory compounds must be removed through additional downstream processing or sufficiently diluted to create environments suitable for most industrially important microbial strains. This study explores the high ferulic acid and n-butanol tolerance in Lactobacillus brevis (L. brevis), a lactic acid bacteria often found in fermentation processes, by global transcriptional response analysis. The transcriptional profile of L. brevis under ferulic acid and butanol stress reveals that the presence of ferulic acid primarily triggers the expression of membrane proteins to counteract ferulic acid induced changes in membrane fluidity and ion leakage. In contrast to the ferulic acid stress response, butanol addition to growing cultures uniquely induced the entire fatty acid synthesis pathway in the midst of a generalized stress response. Overexpression of the rate-limiting acetyl-CoA carboxylase subunits (AccABCD) in E. coli to increase lipid synthesis had no effect on butanol tolerance, suggesting that additional engineering is necessary to produce sufficient levels of appropriate fatty acids to confer butanol tolerance. Several promising routes for understanding both phenolic acid and butanol tolerance have been identified based upon these findings. These insights may be used to guide further engineering of model industrial organisms to better tolerate both classes of inhibitors in processed biomass used for biofuel production. Cultures were grown to OD ~ 0.2 in MRS media (baffled flasks), T = 30 C, 100 rpm. Butanol was then added to the cultures. Samples were harvested 15, 75, and 135 min after butanol addition. Each time point has 3 biological replicates, and dye swaps were incorporated into the microarray experiments.

Dataset Information

A transcriptional study of acidogenic chemostat cells of Clostridium acetobutylicum - cellular behavior in adaptation to n-butanol

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure