Abstract Bafilomycin A1 (BAF A1) is a macrolide antibiotic that, in addition to its antibacterial activity, can induce apoptosis of cancer cells. Glycosylation plays an important role in the modification of antibiotics as it can improve their bioactivity. However, glycosylation of BAF A1 has not been previously reported. Bacillus licheniformis glycosyltransferase (GTs) Bl-YjiC and Bacillus subtilis GTs Bs-YjiC were expressed successfully in a heterologous manner. The glycosylation of BAF A1 with UDP-glucose, UDP-galactose or UDP-N-acetylglucosamine was catalyzed using the enzymes Bl-YjiC and Bs-YjiC. Our results demonstrated that Bl-YjiC can only utilize UDP-glucose as the donor, while Bs-YjiC can utilize all three glycosyl donors. The glycosylation site was demonstrated by MS/MS to be the hydroxyl group at the C21 position of BAF A1. The anti-proliferative effects of glucosyl BAF A1 (BAF-Glc) on HeLa cells indicate that this novel antibiotic is superior to BAF A1. The IC50 for BAF-Glc was determined to be 5.47 μM. Here, we report the production of glycosylated BAF A1 for the first time, and we show that the produced BAF-Glc exhibited better anticancer activity than BAF A1. This work provides theoretical and experimental support for the development of novel anticancer bafilomycins.

中文翻译：

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糖基化巴弗洛霉素的生物合成及抗 HeLa 细胞作用

摘要 Bafilomycin A1 (BAF A1) 是一种大环内酯类抗生素，除具有抗菌活性外，还可诱导癌细胞凋亡。糖基化在抗生素的修饰中起着重要作用，因为它可以提高抗生素的生物活性。然而，以前没有报道过 BAF A1 的糖基化。地衣芽孢杆菌糖基转移酶 (GTs) Bl-YjiC 和枯草芽孢杆菌 GTs Bs-YjiC 以异源方式成功表达。使用酶 Bl-YjiC 和 Bs-YjiC 催化 BAF A1 与 UDP-葡萄糖、UDP-半乳糖或 UDP-N-乙酰氨基葡萄糖的糖基化。我们的结果表明 Bl-YjiC 只能利用 UDP-葡萄糖作为供体，而 Bs-YjiC 可以利用所有三个糖基供体。MS/MS 证明糖基化位点是 BAF A1 C21 位置的羟基。葡萄糖基 BAF A1 (BAF-Glc) 对 HeLa 细胞的抗增殖作用表明这种新型抗生素优于 BAF A1。BAF-Glc 的 IC50 确定为 5.47 μM。在这里，我们首次报告了糖基化 BAF A1 的产生，并且我们表明所产生的 BAF-Glc 表现出比 BAF A1 更好的抗癌活性。该工作为开发新型抗癌巴弗洛霉素提供了理论和实验支持。