Project description:Caldicellulosiruptor saccharolyticus is an extremely thermophilic, Gram-positive anaerobe, which ferments cellulose-, hemicellulose- and pectin-containing biomass to acetate, CO2 and hydrogen. Its broad substrate range, high hydrogen-producing capacity, and ability to co-utilize glucose and xylose, make this bacterium an attractive candidate for microbial bioenergy production. Glycolytic pathways and an ABC-type sugar transporter were significantly up-regulated during growth on glucose and xylose, indicating that C. saccharolyticus co-ferments these sugars unimpeded by glucose-based catabolite repression. The capacity to simultaneously process and utilize a range of carbohydrates associated with biomass feedstocks represents a highly desirable feature of a lignocellulose-utilizing, biofuel-producing bacterium. Keywords: substrate response
Project description:Caldicellulosiruptor saccharolyticus is an extremely thermophilic, Gram-positive anaerobe, which ferments cellulose-, hemicellulose- and pectin-containing biomass to acetate, CO2 and hydrogen. Its broad substrate range, high hydrogen-producing capacity, and ability to co-utilize glucose and xylose, make this bacterium an attractive candidate for microbial bioenergy production. Glycolytic pathways and an ABC-type sugar transporter were significantly up-regulated during growth on glucose and xylose, indicating that C. saccharolyticus co-ferments these sugars unimpeded by glucose-based catabolite repression. The capacity to simultaneously process and utilize a range of carbohydrates associated with biomass feedstocks represents a highly desirable feature of a lignocellulose-utilizing, biofuel-producing bacterium. Keywords: substrate response C. saccharolyticus was subcultured (overnight) 3 times on the substrate of interest in modified DSMZ 640 medium before inoculating a pH-controlled (pH = 7) 1-liter fermentor containing 4 gram substrate per liter. Cells were grown at 70 °C until mid-logarithmic phase (~OD660 = 0.3-0.4) and harvested by centrifugation and rapid cooling to 4 °C and stored at -80 °C. To elucidate the central carbon metabolic pathways and their regulation, transcriptome analysis was performed after growth on glucose, xylose and a 1:1 mixture of both substrates. L-Rhamnose, which was likely to follow another pathway, was used as a reference substrate.
Project description:E. coli TG1 with pBS(Kan)Synhox can produce more hydrogen than TG1/pBS(Kan). To reveal the difference of metabolic activity (gene expression) between these strains in producing hydrogen, the differential gene expression analyses were performed. All samples cultured in complex medium with fructose containg 5 mM IPTG. Experiment Overall Design: Strains: E. coli TG1/pBS(Kan)Synhox and TG1/pBS(Kan) Experiment Overall Design: Medium: Complex with fructose Experiment Overall Design: Hydrogen producing cells Experiment Overall Design: Time: 6 hour
Project description:E. coli TG1 with pBS(Kan)Synhox can produce more hydrogen than TG1/pBS(Kan). To reveal the difference of metabolic activity (gene expression) between these strains in producing hydrogen, the differential gene expression analyses were performed. All samples cultured in complex medium with fructose containg 5 mM IPTG. Keywords: hydrogen production
Project description:We applied high throughput sequencing technology to identify microRNA genes in bighead carp and silver carp. We identified 167 conserved miRNAs in bighead carp and 166 in silver carp. By two computational stragegies, we obtained 39 novel miRNAs in bighead carp and 54 in silver carp, for which, no homologs were found in other species. Several miRNA* sequences were found in our dataset as well, some particular ones might have gene regulation function. Gain and loss of family members were observed in several miRNA families, which partially reflected the fate of miRNA gene duplicates.