Antimicrobial drug resistance is one of the greatest threats facing mankind. Antimicrobial peptides (AMPs) can potentially circumvent drug resistance, probably through a bacterial membrane-disruption mechanism. However, they suffer from low in vivo stability, potential immunogenicity, and difficulty in optimization. The development of antimicrobial peptidomimetics is therefore an emerging research area as they avoid the potential disadvantages of AMPs. Cyclic peptidomimetics are of significant interest since constraints induced by cyclization are expected to further improve their antimicrobial activity. Nonetheless, the report of cyclic oligomeric peptidomimetics for antimicrobial development is rare. Herein, for the first time, we report the design and synthesis of cyclic γ-AApeptides via an on-resin cyclization. These cyclic γ-AApeptides are potent and broad-spectrum active against fungus and multi-drug resistant Gram-positive and Gram-negative bacterial pathogens. Our results demonstrate the potential of cyclic γ-AApeptides as a new class of antibiotics to circumvent drug resistance by mimicking the bactericidal mechanism of AMPs. Meanwhile, the facile synthesis of cyclic γ-AApeptides may further expand the applications of γ-AApeptides in biomedical sciences.
抗菌药耐药性是人类面临的最大威胁之一。抗菌肽(
AMPs)可能通过细菌膜破坏机制来规避耐药性。然而,抗菌肽存在体内稳定性低、潜在免疫原性和难以优化等问题。因此,抗菌
多肽模拟物的开发成为一个新兴的研究领域,因为它们避免了
AMPs 的潜在缺点。环状拟肽物引起了人们极大的兴趣,因为环化引起的限制有望进一步提高它们的抗菌活性。然而,有关环状低聚拟肽物用于抗菌开发的报道却很少见。在此,我们首次报告了通过
树脂环化设计和合成环状δ³-
AA 肽的情况。这些环δ-
AA 肽对真菌和具有多重耐药性的革兰氏阳性和革兰氏阴性细菌病原体具有强效和广谱的活性。我们的研究结果证明了环δ-A肽作为一类新型
抗生素的潜力,它可以通过模仿
AMPs的杀菌机制来规避耐药性。同时,环δ-A肽的简易合成可能会进一步扩大δ-A肽在
生物医学科学中的应用。