Antibacterial to antifungal conversion of neamine aminoglycosides through alkyl modification. Strategy for reviving old drugs into agrofungicides
作者:Cheng-Wei T Chang、Marina Fosso、Yukie Kawasaki、Sanjib Shrestha、Mekki F Bensaci、Jinhua Wang、Conrad K Evans、Jon Y Takemoto
DOI:10.1038/ja.2010.110
日期:2010.11
Many Actinomycetes aminoglycosides are widely used antibiotics. Although mainly antibacterials, a few known aminoglycosides also inhibit yeasts, protozoans and important crop pathogenic fungal oomycetes. Here we show that attachment of a C8 alkyl chain to ring III of a neamine-based aminoglycoside specifically at the 4â³-O position yields a broad-spectrum fungicide (FG08) without the antibacterial properties typical for aminoglycosides. Leaf infection assays and greenhouse studies show that FG08 is capable of suppressing wheat fungal infections by Fusarium graminearumâthe causative agent of Fusarium head blightâat concentrations that are minimally phytotoxic. Unlike typical aminoglycoside action of ribosomal protein translation miscoding, FG08's antifungal action involves perturbation of the plasma membrane. This antibacterial to antifungal transformation could pave the way for the development of a new class of aminoglycoside-based fungicides suitable for use in crop disease applications. In addition, this strategy is an example of reviving a clinically obsolete drug by simple chemical modification to yield a new application.
许多放线菌氨基糖苷类化合物是广泛使用的抗生素。虽然主要是抗菌药,但一些已知的氨基糖苷类药物也能抑制酵母菌、原生动物和重要的作物致病真菌卵菌。在这里,我们展示了将 C8 烷基链连接到氨基糖苷的环 III 上,特别是在 4³-O 位置上,可产生一种广谱杀真菌剂(FG08),但不具有氨基糖苷类典型的抗菌特性。叶片感染试验和温室研究表明,FG08 能够抑制小麦真菌禾谷镰刀菌(Fusarium graminearum)(镰刀菌头枯病的病原菌)的感染,其浓度对植物的毒性极低。与典型的氨基糖苷类药物作用于核糖体蛋白翻译错码不同,FG08 的抗真菌作用涉及对质膜的扰动。这种从抗菌到抗真菌的转变可为开发一类新的氨基糖苷类杀菌剂铺平道路,这类杀菌剂适合用于作物病害。此外,这一策略也是通过简单的化学修饰使临床上过时的药物重新焕发生机并产生新应用的一个范例。