Abstract The alteration of safety-secured yeast is a crucial step before scale applications. Based on previous studies, Pichia pastoris showed great potential and value to improve its biocontrol ability. The original sequences of antimicrobial peptide Ac-AMP2 and MiAMP1 were optimized according to the preference of Pichia pastoris and ligated into pPICZαA plasmid which is emerged as a high-performance vector for transformation and expression. The results of RT-qPCR and Western blotting could imply that pPICZαA/Ac-AMP2 and pPICZαA/MiAMP1 were successfully overexpressed in Pichia pastoris GS115. The peptide concentration of GS115/Ac-AMP2 reached a maximum value of 210 mg L−1 at 60 h while GS115/MiAMP1 was 220 mg L−1 at 96 h. The biocontrol experiment indicated that the recombinant strain GS115/Ac-AMP2 and GS115/MiAMP1 could highly suppress the pathogen Penicillium expansum in vivo, which was respectively 42 % (GS115/Ac-AMP2) and 29.2 % (GS115/MiAMP1) of incidence disease lower than the sterile distilled water treatment. In the case of the experimental results considered, the modified GS115/Ac-AMP2 and GS115/MiAMP1 might be promising biological agent in postharvest applications.

中文翻译：

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毕赤酵母中抗菌肽的重组表达：抑制梨中膨胀青霉的策略

摘要 安全酵母的改造是规模化应用前的关键步骤。基于以往的研究，毕赤酵母显示出提高其生防能力的巨大潜力和价值。根据毕赤酵母的偏好优化抗菌肽 Ac-AMP2 和 MiAMP1 的原始序列，并连接到 pPICZαA 质粒中，该质粒作为转化和表达的高性能载体出现。RT-qPCR 和蛋白质印迹的结果可能意味着 pPICZαA/Ac-AMP2 和 pPICZαA/MiAMP1 在毕赤酵母 GS115 中成功过表达。GS115/Ac-AMP2 的肽浓度在 60 小时达到最大值 210 mg L-1，而 GS115/MiAMP1 在 96 小时达到 220 mg L-1。生防实验表明重组菌株GS115/Ac-AMP2和GS115/MiAMP1在体内对病原菌Penicillium expansum具有高度抑制作用，分别为42%（GS115/Ac-AMP2）和29.2%（GS115/MiAMP1）发病率低于无菌蒸馏水处理。在考虑的实验结果的情况下，修饰的 GS115/Ac-AMP2 和 GS115/MiAMP1 可能是收获后应用中很有前途的生物制剂。