WSSV-VP37小肽在大肠杆菌中的偏爱型表达

Preferential expression of WSSV-VP37 peptide in E. coli

关键词:  偏爱密码子  VP37  大肠杆菌  表达

Key words:  Codon optimization  VP37  Expression

摘要:

选用对虾白斑综合征病毒（White Spot Syndrome Virus, WSSV）囊膜蛋白VP37的功能区段，利用大肠杆菌密码子偏爱性，在氨基酸不变的情况下将VP37中的密码子通过人工合成改为大肠杆菌偏爱型密码子，并克隆至表达载体pBAD/gIIIA中，构成重组载体pBAD/gIIIA-VP37p′。将重组载体转化入大肠杆菌Top10中，在相同条件下用L-阿拉伯糖与未优化的重组菌株Top10-pBAD/gIIIA-VP37p一同诱导。结果显示，与野生型基因VP37p相比，经密码子优化的VP37p′基因表达目的蛋白量占总蛋白的40.5%，明显高于野生型6.5%的目的蛋白表达量。

Abstract:

The expression levels of proteins in Escherichia coli appear to be preferential for some special codons. In order to enhance the expression level, we designed a partial sequence of the WSSV-VP37 gene based on the codons of E. coli so that its expression level would be optimized. The optimized VP37 fragment was ligated to the expression vector pBAD/gIIIA. Then the resulted recombinant pBAD/gIIIA-VP37p′ was transformed into E. coli Top10 and the cells were induced by L-arabinose. SDS-PAGE analysis showed that the content of VP37p′ constituted 40.5% of the total proteins. Compared with the wild type recombinant pBAD/gIIIA-VP37p, the expression level of the optimized recombinant VP37p′ (40.5% of the total proteins) was significantly higher than that of the wild type VP37p (6.5% of the total proteins).