Project description:Whole genome gene expression analysis was examined with Ralstonia eutropha strain H16 cultures grown in PHB production medium (recipe per Peoples and Sinskey, 1989) containing fructose or trioleate as the main carbon source. The goal of this analysis was to determine the identity of the triacylglycerol and fatty acid breakdown genes in R. eutropha strain H16.
Project description:Ralstonia eutropha H16 is well-known to produce poly(3-hydroxybutyrate) [P(3HB)], a kind of polyhydroxyalkanoates attracted as bio-based biodegradable plastics, efficiently as an energy storage material under unbalanced growth conditions. To obtain further extended knowledge of PHA biosynthesis, this study employed quantitative transcriptome analysis based on deep sequencing of complementary DNA generated from RNA (RNA-seq) for R. eutropha H16. Total RNAs were extracted from R. eutropha cells in growth, PHA production, and stationary phases on fructose. rRNAs in the preparation were removed by repeated treatments with magnetic beads specific to bacterial rRNAs, and then the 36 bp sequences were determined by using Illumina high-throughput sequencer. The RNA-seq results supported induction of gene expression for transcription, translation, cell division, peptidoglycan biosynthesis, pilus and flagella assembly, energy conservation, and fatty acid biosynthesis in growth phase, and repression trends for genes involved in central metabolisms in PHA production phase. Interestingly, transcription of genes for Calvin-Benson-Bassham (CBB) cycle and several selected genes for β-oxidation were significantly induced in PHA production phase even when the cells were grown on fructose.
