Project description:Clostridium sp. strain CT7 is a new emerging microbial cell factory with high butanol ratio owing to the non-traditional butanol fermentation mode with uncoupled acetone and 1,3-propanediol formation. Significant change of products profile was shown in glycerol- and glucose-fed strain CT7, especially much higher butanol and lower volatile fatty acids production from glycerol-fed one. However, the mechanism of this interesting phenomenon was still unclear. To better elaborate the bacterial response towards glycerol and glucose, the quantitative proteomic analysis through iTRAQ strategy was performed to reveal the regulated proteomic expression levels under different substrates. Proteomics data showed highly increased proteomic expression levels of proteins related with glycerol utilization and solvent generation under glycerol media. In addition, the up-regulation of hydrogenases, ferredoxins and electron-transferring proteins may attribute to the internal redox balance, while the earlier triggered sporulation response in glycerol-fed media may be associated with the higher butanol fermentation. This study will provide the platform for metabolic engineering of this emerging industrial microorganism for more efficient butanol production from glycerol.
Project description:The goal of the study is to use Next generation sequencing (RNA-seq) and 13C based flux analysis to study the underlying regulation of citric acid metabolism in mixed culture fermentation (glucose and glycerl) of Yarrowia lipolytica. We sequenced the RNA from 4 different samples in the mixed culture (glucose and glycerol) under oxygen excess and limited conditions with 2 replicates each . Transcriptional profiles showed that under oxygen limited conditions, due to deficient mitochondrial activity, citric acid is being consumed back after glycerol exhaustion eventhough glucose is present in excess. Transcriptome and fluxome profiles showed that glucose is mainly directed towards the Pentose phosphate pathway in the dual substrate fermentations.
Project description:In this study, the recombinant Trichoderma reesei strain HJ48 was employed to investigate the differences between anaerobic and aerobic fermentation of glucose, through genome-wide transcription analysis.Analysis of the genes induced under fermentation condition has revealed novel features in T. reesei. Our results how that many genes related to ribosome were expressed more highly under aerobic condition in HJ48.
Project description:The goal of the study is to use Next generation sequencing (RNA-seq) to study the underlying regulation of glycerol metabolism in mixed culture fermentation (glucose and glycerol) of Rhodosporidium toruloides. We sequenced the RNA from 4 different samples in the mixed culture (glucose and glycerol) with 2 replicates each. Transcriptional profiles showed that glycerol might be produced intracellularly and glycerol kinase (GUT1) and glycerol 3–phosphate dehydrogenase (GUT2) enzymes were not down-regulated in the presence of glucose at the transcriptional level. It also showed that this yeast has a different regulation compared to S.cerevisiae. Certain insights into lipid biosynthesis on these mixed cultures are provided at systems level. This analysis provides interesting targets for metabolic engineering in this organism growing on glucose and glycerol.
