In the present work, we used systematic engineering at transport and transcription levels to significantly enhance alkaline α-amylase production in Bacillus subtilis 168M. Signal peptide YwbN' proved to be optimal. Alkaline α-amylase production was elevated by deleting a putative peptide segment of YwbN'. Insertion of arginine (R) between residues 5 and 6 of YwbN'∆p further increased the protein yield. Enhancing positive charges at sites 4 and 10 and decreasing the hydrophobicity of the H-region of YwbN'∆p were critical for improving alkaline α-amylase production in B. subtilis 168M. PHpaII was the optimal promoter, and deleting - 27T or - 31A from PHpaII enhanced the transcription of the target gene. Using a single-pulse feeding-based fed-batch system, alkaline α-amylase activity of B. subtilis 168M P∆-27T was increased by 250.6-fold, compared with B. subtilis 168M A1.

中文翻译：

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运输和转录的系统工程，以提高枯草芽孢杆菌中碱性α-淀粉酶的产生。

在目前的工作中，我们在转运和转录水平上使用系统工程技术来显着增强枯草芽孢杆菌168M中碱性α-淀粉酶的产生。信号肽YwbN'被证明是最佳的。通过删除推测的YwbN'的肽段，提高了碱性α-淀粉酶的产量。在YwbN'∆p的残基5和6之间插入精氨酸（R）进一步提高了蛋白质产量。增加位点4和10的正电荷并降低YwbN'∆p H区域的疏水性对于提高枯草芽孢杆菌168M中碱性α-淀粉酶的产量至关重要。PHpaII是最佳启动子，从PHpaII缺失-27T或-31A可增强靶基因的转录。使用单脉冲进料分批进料系统，枯草芽孢杆菌168M P∆-27T的碱性α-淀粉酶活性提高了250。