Constitutive expression of codon optimized Trichoderma reesei TrCel5A in Pichia pastoris using GAP promoter  

作　　者：Yun Hu Renhui Bai Shaohua Dou Zhimeng Wu Ali Abdulkhani Mohammad Ali Asadollahi Abd El-Fatah Abomohra Fubao Sun 

机构地区：[1]Key Laboratory of Carbohydrate and Biotechnology,and Key Laboratory of Industrial Biotechnology,Ministry of Education,School of Biotechnology,Jiangnan University,Wuxi 214122,China [2]School of Life Science and Biotechnology,Dalian University,Dalian 116622,China [3]Department of Wood and Paper Sciences and Technology,Faculty of Natural Resources,University of Tehran,31585-4314 Karaj,Iran [4]Department of Biotechnology,Faculty of Biological Science and Technology,University of Isfahan,81746-73441 Isfahan,Iran [5]New Energy and Environmental Laboratory,School of Architecture and Civil Engineering,Chengdu University,Chengdu 610106,China

出　　处：《Systems Microbiology and Biomanufacturing》2022年第3期498-506,共9页系统微生物学与生物制造（英文）

基　　金：supported by the National Key Research and Development Program of China(2019YFE0114600);National Natural Science Foundation of China(21776114).

摘　　要：To address the deficient activity of TrCel5A in naturally secreted cellulase preparation,this study used the GAP promoter to induce constitutive expression of Trichoderma reesei TrCel5A in Pichia pastoris.A recombinant TrCel5A was screened out after gene optimization,synthesis,and expression.The biochemical and enzymatic properties of the new recombinant were characterized.As a result,optimization of shake-flask fermentation of the recombinant was obtained at 28℃,2%inoculum volume,an initial pH of 6.0,as well as glycerol and Tween-80 additions of 30 g/L and 6 g/L,respectively.Under the above-optimized conditions,the recombinant produced 14.8 U/mL of the enzyme activity at 96 h of fermentation.To further enhance enzyme production,pilot-scale cultivation was evaluated using 5-L bioreactors.Using high-cell-density fermentation,the recombinant strain increased enzyme activity to 130.4 U/ml and protein content to 2.49 g/L.In addition,the kinetic factors,including K_(m) and V_(max) values for TrCel5A,were detected to be 5.1 mg/mL and 265.9μmol/(min.mg),respectively.Thus,TrCel5A was effectively expressed in P.pastoris under the GAP promoter,and it demonstrated its potential in commercially relevant enzyme hydrolysis of lignocellulosic biomass.

关 键 词：Trichoderma reesei endoglucanase(Cel5A) Pichia pastoris GAP promoter Constitutive expression Fermentation optimization CMC enzyme activity 

分 类 号：Q78[生物学—分子生物学]