Cecropin AD (CAD) is a hybrid peptide composed of 37 amino acids with the characters of strong antibacterial, antitumor properties and no hemolytic activity, which was regarded as a promising antibiotic candidate. Thus, a safe method to produce Cecropin AD is necessary to be found. In the study, Bacillus subtilis WB800N was employed as host strain. The CAD coding sequence fused with the signal peptide of SP_sacB, the 6 × His gene and the gene of small ubiquitin-like modifier were cloned into the maltose-inducible vector pGJ148. Under the induction by 6% maltose, the recombinant fusion protein was successfully expressed and detected in culture substrate. An optimized amount (26.4 mg/L) of the recombinant CAD was purified of culture supernatant. After purification and digestion, the recombinant CAD was harvested about 4.5 mg/L with a purity of 93%. Recombinant CAD exhibited similar antimicrobial activity with synthetic CAD. This shows that the production of CAD in maltose-induced Bacillus subtilis expression system is a relatively safe method, which is vital for the application of CAD in animal husbandry production.

中文翻译：

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麦芽糖通过SUMO技术诱导枯草芽孢杆菌WB800N表达天蚕素AD。

Cecropin AD（CAD）是由37个氨基酸组成的杂合肽，具有强大的抗菌，抗肿瘤特性和无溶血活性，被认为是一种很有前途的抗生素候选物。因此，必须找到一种安全的方法来生产Cecropin AD。在研究中，枯草芽孢杆菌WB800N被用作宿主菌株。与SP _sacB信号肽融合的CAD编码序列之后，将6×His基因和小的泛素样修饰基因克隆到麦芽糖诱导型载体pGJ148中。在6％麦芽糖诱导下，重组融合蛋白成功表达并在培养底物中检测到。从培养上清液中纯化最适量（26.4 mg / L）的重组CAD。纯化和消化后，收获重组CAD约4.5 mg / L，纯度为93％。重组CAD表现出与合成CAD相似的抗菌活性。这表明在麦芽糖诱导的枯草芽孢杆菌表达系统中生产CAD是一种相对安全的方法，这对于将CAD用于畜牧业生产至关重要。