Enhancement of polyhydroxyalkanoate production by co-feeding lignin derivatives with glycerol in Pseudomonas putida KT2440

Abstract Background Efficient utilization of all available carbons from lignocellulosic biomass is critical for economic efficiency a bioconversion process to produce renewable bioproducts. However, the metabolic responses that enable Pseudomonas putida utilize mixed carbon sources generate reducing power and polyhydroxyalkanoate (PHA) remain unclear. Previous research has mainly focused on different fermentation strategies, including sequential feeding xylose as growth stage substrate octanoic acid PHA-producing substrate, glycerol sole co-feeding lignin glucose. This study developed new strategy—co-feeding derivatives such benzoate, vanillin, vanillic in KT2440—for first time, which simultaneously improved both cell PHA production. Results Co-feeding (i.e. acid) P. KT2440 was shown time increase dry weight (CDW) by 9.4–16.1% content 29.0–63.2%, respectively, compared with alone. GC–MS results revealed addition decreased distribution long-chain monomers (C10 C12) 0.4–4.4% increased short-chain (C6 C8) 0.8–3.5%. The 1 H– 13 C HMBC, HSQC, H COSY NMR analysis confirmed (C6–C14) were produced when fed bacteria alone or together derivatives. Moreover, investigation glycerol/benzoate/nitrogen ratios showed benzoate acted an independent factor synthesis. Furthermore, H, 31 P metabolite mass spectrometry-based quantitative proteomics measurements suggested stimulated oxidative-stress responses, enhanced consumption, altered intracellular NAD + /NADH NADPH/NADP up-regulating proteins involved energy generation storage processes, Entner–Doudoroff (ED) pathway, reductive TCA route, trehalose degradation, fatty ? -oxidation, biosynthesis. Conclusions work demonstrated effective co-carbon strategy improve content/yield convert into value-added products KT2440. break-down other sources, glycerol, been efficient way production involvement aromatic degradation favours further utilization, combination metabolomics sheds light regulatory mechanisms cellular redox balance potential genetic targets higher conversion efficiency.