Antimicrobial peptides are an important weapon against invading pathogens and are potential candidates as novel antibacterial agents, but their antifungal activities are not fully developed. In this study, a set of imperfectly amphipathic peptides was developed based on the imperfectly amphipathic palindromic structure R_n(XRXXXRX)R_n (n = 1, 2; X represents L, I, F, or W), and the engineered peptides exhibited high antimicrobial activities against all fungi and bacteria tested (including fluconazole-resistant Candida albicans), with geometric mean (GM) MICs ranging from 2.2 to 6.62 μM. Of such peptides, 13 (I6) (RRIRIIIRIRR-NH₂) that was Ile rich in its hydrophobic face had the highest antifungal activity (GM_fungi = 1.64 μM) while showing low toxicity and high salt and serum tolerance. It also had dramatic LPS-neutralizing propensity and a potent membrane-disruptive mechanism against microbial cells. In summary, these findings were useful for short AMPs design to combat the growing threat of drug-resistant fungal and bacterial infections.

中文翻译：

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与新型不完全两亲回文肽抗药性真菌。

抗菌肽是抵抗病原体入侵的重要武器，是新型抗菌剂的潜在候选者，但其抗真菌活性尚未得到充分开发。在这项研究中，基于不完全两亲回文结构R _n（XRXXXRX）R _n（n = 1、2； X代表L，I，F或W），开发了一组不完全两亲肽。对所有测试的真菌和细菌（包括耐氟康唑的白色念珠菌）具有很高的抗菌活性，几何平均（GM）MIC范围为2.2至6.62μM。在这些肽中，13（I6）（RRIRIIIRIRR-NH ₂）富含疏水分子的Ile具有最高的抗真菌活性（GM_真菌= 1.64μM），同时显示出低毒性，高盐和血清耐受性。它也具有显着的LPS中和倾向和针对微生物细胞的强大的破坏膜的机制。总而言之，这些发现对于短时间AMP的设计很有用，以抵抗耐药真菌和细菌感染的日益增长的威胁。