Peng Li, Xu Zhinan, Fang Xiangming, Wang Fang, Yang Sheng, Cen Peilin
Institute of Bioengineering, Department of Chemical Engineering and Bioengineering Zhejiang University, Hangzhou 310027, The People's Republic of China.
Protein Pept Lett. 2004 Aug;11(4):339-44. doi: 10.2174/0929866043406760.
Human beta-defensin-2 (hBD2) is a small antimicrobial peptide with potential as a therapeutic agent. The effect of codon usage on the expression of hBD2 in Escherichia coli was studied. Two coding sequences encoding the same hBD2 precursor were both expressed as fusion protein with thioredoxin in E. coli BL21 (DE3). One is the wild-type human cDNA and the other is a gene synthesized by a PCR-based method in which rare codons were altered to those frequently used in E. coli. The expression level of recombinant hBD2 was over 50% of the total cellular protein when the synthetic gene with preferential codons was employed which was a 9-fold enhancement over the wild-type cDNA. The result shows the codon bias of the host was a major barrier in high-level expression of recombinant hBD2 and suggests a similar approach may be used in the expression of other defensins in E. coli.
人β-防御素2（hBD2）是一种具有治疗潜力的小抗菌肽。研究了密码子使用对hBD2在大肠杆菌中表达的影响。编码相同hBD2前体的两个编码序列均在大肠杆菌BL21（DE3）中作为与硫氧还蛋白的融合蛋白表达。一个是野生型人cDNA，另一个是通过基于PCR的方法合成的基因，其中稀有密码子被改变为大肠杆菌中常用的密码子。当使用具有优先密码子的合成基因时，重组hBD2的表达水平超过总细胞蛋白的50%，这比野生型cDNA提高了9倍。结果表明宿主的密码子偏好是重组hBD2高水平表达的主要障碍，并表明类似的方法可用于在大肠杆菌中表达其他防御素。
