作　　者： ; ; ; ; ; ; ;

机构地区： 广东省农业科学院

出　　处： 《农业生物技术学报》 2008年第1期154-157,共4页

摘　　要： 在α-螺旋抗菌肽序列比较和两亲性分析的基础上,提取序列模板,计算机辅助(螺旋轮法)设计出新型抗菌肽模式肽PGYa(peptide以Gly开头,以Tyr-NH2结尾),然后选用毕赤酵母(Pichia pastoris)偏爱密码子,设计合成了PGYa基因(rPCR法)。所合成的基因全长为94bp,并在其N端引入Kex2裂解位点,以保证表达抗菌肽具有天然N端。基因克隆入pPICZα-A质粒,构建分泌型酵母表达载体pPICZα-A-PGYa。在AOX1(醇氧化酶)启动子调控下,PGYa蛋白获得分泌表达,其分子量约为2.8kD。初步抑菌(Escherichia coli DH5α)活性显示,PGYa有较好的抗菌活性。 Based on sequence analogy and amphipathicity analyse of a-helical antimicrobial peptides, a sequence template was extracted. The model antimicrobial peptide PGYa（peptide beginning with Gly and ending with Tyr-NH2） was designed by virtue of the template and computer-aided design subsequently. Using the optimal condon of Pichia pastoris, PGYa gene with 94 bp length were achieved through a recursive PCR strategy. Especially a Kex2 signal cleavage site was fused in 5′ end of the antibacterial peptide gene to make sure the expression protein with nature N-terminal. The modified antibacterial peptide gene was then cloned into the pPICZα-A vector to construct the recombinant expression vector pPICZα-A-PGYa, and transformed into yeast host strain X-33. Under the control of the promoter AOXI （alcohol oxidase 1）, the PGYa protein with a molecular weight of 2.8 kD was expressed in supernatant protein. Preliminary antibacterial assays showed that PGYa has a potent antibacterial activity against Escher/chia coli DH5α.

关 键 词： 螺旋抗菌肽模式肽 两亲性 毕赤酵母 分泌表达

领　　域： [农业科学]