@article{ajmsm2014211,
author={{Lao, Xingzhen and Liu, Meng and Zhang, Fang and Zheng, Heng},
title={Orthogonal Test Design for Optimization of the Expression of Thymosin ¦Á1 and Thymosin ¦Á1- iRGD Gene in Engineered <i>E.coli</i> BL21 Strain},
journal={American Journal of Medical Sciences and Medicine},
volume={2},
number={1},
pages={1--6},
year={2014},
url={http://pubs.sciepub.com/ajmsm/2/1/1},
issn={2327-6657},
abstract={In order to increase the expression of fusion protein of thymosin ¦Á1(T¦Á1) and thymosin ¦Á1-iRGD (T¦Á1-iRGD) by the engineered E. coli BL21 strain, containing pET32a-Trx-T¦Á1 and pET32a-Trx-T¦Á1-iRGD plasmid, respectively. The<b> </b>key parameters that influenced the expression of T¦Á1 and T¦Á1-iRGD were optimized by employing an orthogonal experiment [L<SUB>25</SUB>(5)<SUP>3</SUP>], including OD<SUB>600nm</SUB> before induction, lactose concentration and induction time, each with five levels. The intensity of target protein band was scanned as a quantitative measure method of the protein expression, after electrophoresis separation of total soluble protein on SDS-PAGE. For T¦Á1 fusion protein, the optimal conditions were OD<SUB>600nm</SUB>=0.6 before induction, 2.5 mmol/L lactose concentration, 4 hours induction time. Target protein expression levels could be achieved 32.8% of the total soluble proteins. For T¦Á1-iRGD fusion protein, the optimal conditions were OD<SUB>600nm</SUB>=0.8 before induction, 7.5mmol/L lactose concentration, 4 hours for induction. Under the condition, the amount of expressed protein could reach 33.8% of the total soluble proteins. Whereas before optimization, the expression level of T¦Á1 and T¦Á1-iRGD fusion proteins were 20.6% and 9.0% of the total soluble proteins, respectively. The orthogonal test was proved to be an effective method to optimize the expression of target proteins.},
doi={10.12691/ajmsm-2-1-1}
publisher={Science and Education Publishing}
}