Light induced expression of β-glucosidase in Escherichia coli with autolysis of cell

BMC Biotechnology

Research Article

Youxue Lu¹  Yu Pan¹  Wei Fang²  Fei Chang³  Xianbing Zhang³  Yazhong Xiao³  Zemin Fang³ 

[1] School of Life Sciences, Anhui University, 230601, Hefei, Anhui, China;School of Life Sciences, Anhui University, 230601, Hefei, Anhui, China;Anhui Key Laboratory of Modern Biomanufacturing, 230601, Hefei, Anhui, China;School of Life Sciences, Anhui University, 230601, Hefei, Anhui, China;Anhui Key Laboratory of Modern Biomanufacturing, 230601, Hefei, Anhui, China;Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, 230601, Hefei, Anhui, China;

关键词: Light induction;    β-Glucosidase;    Escherichia coli;    Autolysis;    Immobilization;    Cellulose;   

DOI  :  10.1186/s12896-017-0402-1

 received in 2017-06-28, accepted in 2017-10-31,  发布年份 2017

来源: Springer

【 摘 要 】

Backgroundβ-Glucosidase has attracted substantial attention in the scientific community because of its pivotal role in cellulose degradation, glycoside transformation and many other industrial processes. However, the tedious and costly expression and purification procedures have severely thwarted the industrial applications of β-glucosidase. Thus development of new strategies to express β-glucosidases with cost-effective and simple procedure to meet the increasing demands on enzymes for biocatalysis is of paramount importance.ResultsLight activated cassette YF1/FixJ and the SRRz lysis system were successfully constructed to produce Bgl1A(A24S/F297Y), a mutant β-glucosidase tolerant to both glucose and ethanol. By optimizing the parameters for light induction, Bgl1A(A24S/F297Y) activity reached 33.22 ± 2.0 U/mL and 249.92 ± 12.25 U/mL in 250-mL flask and 3-L fermentation tank, respectively, comparable to the controls of 34.02 ± 1.96 U/mL and 322.21 ± 10.16 U/mL under similar culture conditions with IPTG induction. To further simplify the production of our target protein, the SRRz lysis gene cassette from bacteriophage Lambda was introduced to trigger cell autolysis. As high as 84.53 ± 6.79% and 77.21 ± 4.79% of the total β-glucosidase were released into the lysate after cell autolysis in 250 mL flasks and 3-L scale fermentation with lactose as inducer of SRRz. In order to reduce the cost of protein purification, a cellulose-binding module (CBM) from Clostridium thermocellum was fused into the C-terminal of Bgl1A(A24S/F297Y) and cellulose was used as an economic material to adsorb the fusion enzyme from the lysate. The yield of the fusion protein could reach 92.20 ± 2.27% after one-hour adsorption at 25 °C.ConclusionsWe have developed an efficient and inexpensive way to produce β-glucosidase for potential industrial applications by using the combination of light induction, cell autolysis, and CBM purification strategy.

【 授权许可】

CC BY   
© The Author(s). 2017