Enhanced Poly(ethylene terephthalate) Hydrolase Activity by Protein Engineering

Enhanced Poly(ethylene terephthalate) Hydrolase

Activity by Protein Engineering

Yuan Ma;Mingdong Yao;Bingzhi Li;Mingzhu Ding;Bo He;Si Chen;Xiao Zhou;Yingjin Yuan

【期刊名称】《工程（英文）》 【年(卷),期】2018(004)006

【摘要】Poly(ethylene terephthalate) hydrolase (PETase) from Ideonella sakaiensis exhibits a strong ability to degrade poly(ethylene terephthalate) (PET) at room temperature,and is thus regarded as a potential

tool

to

solve

the

issue

of

polyester

plastic

pollution.Therefore,we explored the interaction between PETase and the substrate

(a

dimer

of

the

PET

monomer

ethylene

terephthalate,2PET),using a model of PETase and its substrate.In this study,we focused on six key residues around the substrate-binding groove in order to create novel high-efficiency PETase mutants through protein engineering.These PETase mutants were designed and tested.The

enzymatic

activities

of

the

R61A,L88F,and

I179F

mutants,which were obtained with a rapid cell-free screening system,exhibited 1.4 fold,2.1 fold,and 2.5 fold increases,respectively,in comparison with wild-type PETase.The I179F mutant showed the highest activity,with the degradation rate of a PET film reaching 22.5 mg per μmol·L-1 PETase per day.Thus,this study has created enhanced artificial