RNA-seq analysis of FNR overexpressed in Cupriavidus necator H16

This study aimed to improve beta-caryophyllene production in Cupriavidus necator H16 through the manipulation of global regulatory factors. And global regulator FNR (H16_B2074) was chosen for overexpression in engineering C. necator H16, based on previous reports demonstrating their positive effects on the biosynthesis of diverse metabolites in different microbial chassis. Engineering strains C. necator H16 delta phaC1AB1 harboring plasmid p2MCBAD-QHS (CNQ02) and C. necator H16 delta phaC1AB1 delta ldh: Plac-fnr harboring plasmid p2MCBAD-QHS (CNQ30) were constructed for this analysis, and their relevant characteristics are summarized in below.For RNA-seq analysis, CNQ02 and CNQ30 were heterotrophically cultivated using fructose as the carbon source. Cells were induced at an OD600 of 0.8 and harvested 12 hours after induction. At the time of harvest, the OD600 values of CNQ02 and CNQ30 were approximately 2.4, with corresponding beta-caryophyllene titers of 0.18 mg/L and 0.43 mg/L, respectively. Subsequently, comparative transcriptomic analysis was performed to investigate the underlying reasons for this difference in beta-caryophyllene production.