Effective production of Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) by engineered Halomonas bluephagenesis grown on glucose and 1,4-Butanediol

• Published in: Bioresource technology 2022-07, Vol.355, p.127270-127270, Article 127270
• Main Authors: Zhang, Lizhan, Ye, Jian-Wen, Zhang, Xu, Huang, Wuzhe, Zhang, Zhongnan, Lin, Yina, Zhang, Ge, Wu, Fuqing, Wang, Ziyu, Wu, Qiong, Chen, Guo-Qiang
• Format: Article
• Language: English
• Subjects: 1,4-butanediol; 4-Hydroxybutyrate; Halomonas; Metabolic Engineering; P34HB; PHB; Synthetic biology; γ-butyrolactone
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2022.127270

•Recombinant H. bluephagenesis produced P(3HB-co-4HB) from glucose and BDO.•H. bluephagenesis TDB141ΔAC produced 75 g L−1P(3HB-co-14 mol% 4HB).•Higher 4HB molar ratio (>26 mol%) of P(3HB-co-4HB) can be achieved by TDB141ΔAC.•The bioconversion rate of BDO to 4HB monomer reaches 86% in fed-batch study.•Life cycle analysis indicates BDO as an environmentally friendly counterpart of GBL. Halomonas bluephagenesis has been engineered to produce flexible copolymers P34HB or poly(3-hydroxybutyrate-co-4-hydroxybutyrate) from glucose and petrol-chemical precursor, γ-butyrolactone. Herein, gene cluster aldD-dhaT was constructed in recombinant H. bluephagenesis for catalyzing 1,4-butanediol (BDO) into 4-hydroxybutyrate, which could grow to 86 g L−1 dry cell mass (DCM) containing 77 wt% P(3HB-co-14 mol% 4HB) in 7-L bioreactor fed with glucose and bio-based BDO. Furthermore, 4HB monomer ratio could be increased to 16 mol% by engineered H. bluephagenesis TDH4-WZY254 with defected outer-membrane. Upon deletion of 4HB degradation pathway, followed by aldD-dhaT integration, the resulted H. bluephagenesis TDB141ΔAC was grown to 95 g L−1 DCM containing 79 wt% P(3HB-co-14 mol% 4HB) with a BDO conversion efficiency of 86% under fed-batch fermentation. Notably, 4HB molar ratio can be significantly improved to 21 mol% with negligible effects on cell growth and P34HB synthesis by adding 50% more BDO. This study successfully demonstrated a fully bio-based P34HB effectively produced by H. bluephagenesis.