Evans Laboratory of Chemistry , The Ohio State University , 100 West 18th Avenue , Columbus , Ohio 43210 , United States.
ACS Chem Biol. 2019 Mar 15;14(3):449-458. doi: 10.1021/acschembio.8b01087. Epub 2019 Feb 20.
Antimicrobial peptides (AMPs) are short, amphipathic peptides that are typically cationic in sequence and display broad-spectrum activity against bacteria, fungi, and protists. Herein, we report the effect of appending the amino terminal copper and nickel binding motif (ATCUN) to Sub5. The Cu-ATCUN derivatives show a two- to three-fold increase in antimicrobial activity for a variety of microbes, relative to Sub5, with MICs as low as 0.3 ± 0.1 μM toward Enterococcus faecium. Sub5 and the ATCUN derivatives bind both plasmid DNA and 16s A-site rRNA with low micromolar affinity. Native Sub5 and the metallopeptide derivatives were shown to promote damage against DNA to similar extents in cellular studies against both Escherichia coli and Staphylococcus epidermidis, with an almost threefold higher activity against the latter organism. Liposome experiments show that the metallopeptides have a greater affinity for model membranes of E. coli and S. aureus relative to Sub5, which correlates with their enhanced antimicrobial activity. Sub5 and the metalloderivatives also display no cytotoxicity toward adult human dermal fibroblasts. Addition of the ATCUN motif conferred the ability to promote lipid oxidation toward E. coli and S. epidermidis and enhanced membrane permeability, as evidenced by the extent of ATP leaked from cellular membranes relative to Sub5 alone. These data suggest that Cu-ATCUN derivatives inhibit microbes through multiple modes of action, resulting in an enhancement in their overall potency.
抗菌肽（AMPs）是一类短肽，具有两亲性，通常在序列上带正电荷，对细菌、真菌和原生动物具有广谱活性。在此，我们报告了在 Sub5 的氨基末端添加铜和镍结合基序（ATCUN）的效果。与 Sub5 相比，Cu-ATCUN 衍生物对各种微生物的抗菌活性提高了两到三倍，对粪肠球菌的 MIC 低至 0.3±0.1 μM。Sub5 和 ATCUN 衍生物以低微摩尔亲和力结合质粒 DNA 和 16s A-site rRNA。在针对大肠杆菌和表皮葡萄球菌的细胞研究中，天然 Sub5 和金属肽衍生物对 DNA 的损伤程度相似，对后者的活性几乎高出三倍。脂质体实验表明，与 Sub5 相比，金属肽对大肠杆菌和金黄色葡萄球菌的模型膜具有更高的亲和力，这与其增强的抗菌活性相关。Sub5 和金属衍生物对成人皮肤成纤维细胞也没有细胞毒性。添加 ATCUN 基序使它们能够促进大肠杆菌和表皮葡萄球菌的脂质氧化，并增强膜通透性，这可以通过相对于单独的 Sub5 从细胞膜漏出的 ATP 量来证明。这些数据表明，Cu-ATCUN 衍生物通过多种作用机制抑制微生物，从而提高其整体效力。
