Potential one-step strategy for PET degradation and PHB biosynthesis through co-cultivation of two engineered microorganisms  

作　　者：Pan Liu Tong Zhang Yi Zheng Qingbin Li Tianyuan Su Qingsheng Qi 

机构地区：[1]State Key Laboratory of Microbial Technology,Shandong University,Qingdao 266237,China

出　　处：《Engineering Microbiology》2021年第1期3-10,共8页工程微生物学（英文）

基　　金：funding from the National Natural Science Foundation of China(grant numbers:Institute of Microbiology,Chi-nese Academy of Sciences:31961133016;Beijing Institute of Technol-ogy:31961133015;Shandong University:31961133014)and the Na-tional Key Research and Development Program of China(grant num-ber:2019YFA0706900)and was supported by European Union’s Hori-zon 2020 research and innovation programme under grant agreement No.870292(BIOICEP).

摘　　要：The management and recycling of plastic waste is a challenging global issue.Polyethylene terephthalate(PET),one of the most widely used synthetic plastics,can be hydrolyzed by a series of enzymes.However,upcycling the resulting monomers is also a problem.In this study,we designed a co-cultivation system,in which PET degradation was coupled with polyhydroxybutyrate(PHB)production.First,PETase from Ideonalla sakaiensis was expressed in Yarrowia lipolytica Po1f with a signal peptide from lipase.The engineered PETase-producing Y.lipolytica was confirmed to hydrolyze bis(2-hydroxyethyl)terephthalate(BHET)and PET powder into the monomers terephthalate(TPA)and ethylene glycol(EG).Simultaneously,a TPA-degrading Pseudomonas stutzeri strain isolated from PET waste was transformed with a recombinant plasmid containing the phb CAB operon from Ralstonia eutropha,which encodes enzymes for the biosynthesis of PHB.The two co-cultivated engineered microbes could directly hydrolyze BHET to produce the bioplastic PHB in one fermentation step.During this process,5.16 g/L BHET was hydrolyzed in 12 h,and 3.66 wt%PHB(3.54 g/L cell dry weight)accumulated in 54 h.A total of 0.31g/L TPA was produced from the hydrolyzation of PET in 228 h.Although PHB could not be synthesized directly from PET because of the low hydrolyzing efficiency of PETase,this study provides a new strategy for the biodegradation and upcycling of PET waste by artificial microflora.

关 键 词：Polyethylene terephthalate Upcycling POLYHYDROXYBUTYRATE PETase co-cultivation Yarrowia lipolytica Pseudomonas stutzeri 

分 类 号：TQ3[化学工程]