Geographic Variability and Anti-Staphylococcal Activity of the Chrysophaentins and Their Synthetic Fragments
作者:Jessica L. Keffer、Jared T. Hammill、John R. Lloyd、Alberto Plaza、Peter Wipf、Carole A. Bewley
DOI:10.3390/md10051103
日期:——
Drug-resistant Staphylococcus aureus is a continuing public health concern, both in the hospital and community settings. Antibacterial compounds that possess novel structural scaffolds and are effective against multiple S. aureus strains, including current drug-resistant ones, are needed. Previously, we have described the chrysophaentins, a family of bisdiarylbutene macrocycles from the chrysophyte alga Chrysophaeum taylori that inhibit the growth of S. aureus and methicillin-resistant S. aureus (MRSA). In this study we have analyzed the geographic variability of chrysophaentin production in C. taylori located at different sites on the island of St. John, U.S. Virgin Islands, and identified two new linear chrysophaentin analogs, E2 and E3. In addition, we have expanded the structure activity relationship through synthesis of fragments comprising conserved portions of the chrysophaentins, and determined the antimicrobial activity of natural chrysophaentins and their synthetic analogs against five diverse S. aureus strains. We find that the chrysophaentins show similar activity against all S. aureus strains, regardless of their drug sensitivity profiles. The synthetic chrysophaentin fragments indeed mimic the natural compounds in their spectrum of antibacterial activity, and therefore represent logical starting points for future medicinal chemistry studies of the natural products and their analogs.
耐药性金黄色葡萄球菌仍然是一个持续的公共卫生问题,无论是在医院还是社区环境中。需要具有新型结构骨架的抗菌化合物,这些化合物能有效对抗包括当前耐药菌株在内的多种金黄色葡萄球菌株。我们之前描述了黄藻类藻类Chrysophaeum taylori中一种名为chrysophaentins的双芳基丁烯大环家族,这些化合物可以抑制金黄色葡萄球菌及耐甲氧西林金黄色葡萄球菌(MRSA)的生长。在本研究中,我们分析了位于美国维尔京群岛圣约翰岛不同地点的C. taylori中chrysophaentin的地理变异性,并鉴定了两种新的线性chrysophaentin类似物,E2和E3。此外,我们通过合成包含chrysophaentins保守部分的片段,扩展了结构-活性关系,并确定了天然chrysophaentins及其合成类似物对五种不同金黄色葡萄球菌株的抗菌活性。我们发现,chrysophaentins对所有金黄色葡萄球菌株的活性相似,无论其耐药性特征如何。合成的chrysophaentin片段的确在抗菌活性谱上模仿了天然化合物,因此为未来对天然产品及其类似物的药物化学研究提供了合理的起点。