Wu Quanlong, Deng Mengyin, Mao Ruoyu, Yang Na, Hao Ya, Cao Manli, Teng Da, Wang Jianhua
Gene Engineering Laboratory, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Innovative Team of Antimicrobial Peptides and Alternatives to Antibiotics, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Gels. 2025 Jan 13;11(1):63. doi: 10.3390/gels11010063.
, a prevalent zoonotic pathogen, poses a significant threat to skin wound infections. This study evaluates the bactericidal efficacy of self-assembled peptide hydrogels, PPI45 and PPI47, derived from the defensin-derived peptide PPI42, against ATCC43300. The high-level preparation of PPI45 and PPI47 was achieved with yields of 1.82 g/L and 2.13 g/L, which are 2.19 and 2.60 times the yield of PPI42. Additionally, the critical micelle concentrations (CMCs) of the peptides at pH 7.4 for PPI42, PPI45, and PPI47 were determined to be 245 µg/mL, 973 µg/mL, and 1016 µg/mL, respectively. At a concentration of 3 mg/mL, the viscosities of the gels were 52,500 mPa·s, 33,700 mPa·s, and 3480 mPa·s for PPI42, PPI45, and PPI47. Transmission electron microscopy (TEM) revealed that all peptides exhibited long, pearl necklace-like protofibrils. These peptides demonstrated potent bactericidal activity, with a minimal inhibitory concentration (MIC) of 4-16 µg/mL against , and a sustained effect post-drug clearance. Flow cytometry analysis after 2×MIC peptides treatment for 2 h revealed a 20-38% membrane disruption rate in bacteria, corroborated by scanning electron microscopy (SEM) observations of membrane damage and bacterial collapse. The peptide treatment also led to reduced hyperpolarized membrane potential. In vitro safety assessments indicated minimal hemolytic activity on murine red blood cells and low cytotoxicity on human immortalized epidermal cells (HaCaT). In summary, this work lays a valuable cornerstone for the future design and characterization of self-assembling antimicrobial peptides hydrogels to combat infection.
作为一种普遍存在的人畜共患病原体，对皮肤伤口感染构成重大威胁。本研究评估了源自防御素衍生肽PPI42的自组装肽水凝胶PPI45和PPI47对ATCC43300的杀菌效果。PPI45和PPI47的高产率制备得以实现，产量分别为1.82 g/L和2.13 g/L，分别是PPI42产量的2.19倍和2.60倍。此外，在pH 7.4条件下，PPI42、PPI45和PPI47肽的临界胶束浓度（CMC）分别测定为245 µg/mL、973 µg/mL和1016 µg/mL。在3 mg/mL的浓度下，PPI42、PPI45和PPI47凝胶的粘度分别为52500 mPa·s、33700 mPa·s和3480 mPa·s。透射电子显微镜（TEM）显示，所有肽均呈现出长的、珍珠项链状的原纤维。这些肽表现出强大的杀菌活性，对……的最小抑菌浓度（MIC）为4 - 16 µg/mL，且在药物清除后仍有持续效果。用2×MIC肽处理2小时后的流式细胞术分析显示，细菌的膜破坏率为20 - 38%，扫描电子显微镜（SEM）对膜损伤和细菌崩溃的观察证实了这一点。肽处理还导致超极化膜电位降低。体外安全性评估表明对小鼠红细胞的溶血活性极小，对人永生化表皮细胞（HaCaT）的细胞毒性低。总之，这项工作为未来设计和表征用于对抗……感染的自组装抗菌肽水凝胶奠定了宝贵的基础。
