Lu Chengyu, Liu Lingling, Ma Chengbang, Di Liuqing, Chen Tianbao
Jiangsu Provincial TCM Engineering Technology Research Centre of Highly Efficient Drug Delivery System (DDS), Nanjing University of Chinese Medicine, Nanjing, China.
Natural Drug Discovery Group, Faculty of Medicine, Health and Life Sciences, School of Pharmacy, Queen's University Belfast, Belfast, UK.
J Genet Eng Biotechnol. 2022 May 23;20(1):76. doi: 10.1186/s43141-022-00366-9.
Many active peptides have been found in frog skin secretions. In this paper, our research focused on Pelophylax nigromaculatus and found a broad-spectrum antimicrobial peptide Nigrocin-PN based on the molecular cloning technique. Thereafter, the "Rana box" function was briefly studied by two mutated peptides (Nigrocin-M1 and Nigrocin-M2). Furthermore, in vitro and in vivo assays were used to characterize the peptide's biofunctions, and the peptide's function in treating multidrug-resistant pathogens was also studied.
Nigrocin-PN not only displayed potent antimicrobial abilities in vitro but also significantly ameliorated pulmonary inflammation induced by Klebsiella pneumoniae in vivo. By comparing, leucine-substituted analogue Nigrocin-M1 only displayed bactericidal abilities towards gram-positive bacteria, while the shorter analogue Nigrocin-M2 lost this function. More strikingly, Nigrocin-PN exhibited synergistic effects with commonly used antibiotics; in vitro evolution experiments revealed that coadministration between Nigrocin-PN and ampicillin could delay Staphylococcus aureus antibiotic resistance acquisition. Kinetics and morphology studies indicate that antibacterial mechanisms involved membrane destruction. Furthermore, toxicities and anticancer abilities of these peptides were also studied; compared to two analogues, Nigrocin-PN showed mild haemolytic activity and indistinctive cytotoxicity towards normal cell lines HMEC-1 and HaCaT.
A broad-spectrum antimicrobial peptide Nigrocin-PN was discovered from the skin secretion of Pelophylax nigromaculatus. Structurally, "Rana box" played a crucial role in reducing toxicities without compromising antibacterial abilities, and Nigrocin-PN could be a desired therapeutic candidate.
在蛙皮分泌物中发现了许多活性肽。在本文中，我们以黑斑侧褶蛙为研究对象，基于分子克隆技术发现了一种广谱抗菌肽Nigrocin-PN。此后，通过两种突变肽（Nigrocin-M1和Nigrocin-M2）对“蛙盒”功能进行了简要研究。此外，还采用体外和体内试验来表征该肽的生物功能，并研究了该肽在治疗多重耐药病原体方面的作用。
Nigrocin-PN不仅在体外表现出强大的抗菌能力，而且在体内能显著减轻肺炎克雷伯菌诱导的肺部炎症。相比之下，亮氨酸取代类似物Nigrocin-M1仅对革兰氏阳性菌具有杀菌能力，而较短的类似物Nigrocin-M2则失去了该功能。更引人注目的是，Nigrocin-PN与常用抗生素表现出协同作用；体外进化实验表明，Nigrocin-PN与氨苄西林联合使用可延缓金黄色葡萄球菌抗生素耐药性的产生。动力学和形态学研究表明，抗菌机制涉及膜破坏。此外，还研究了这些肽的毒性和抗癌能力；与两种类似物相比，Nigrocin-PN对正常细胞系HMEC-1和HaCaT表现出轻微的溶血活性和不明显的细胞毒性。
从黑斑侧褶蛙的皮肤分泌物中发现了一种广谱抗菌肽Nigrocin-PN。在结构上，“蛙盒”在不影响抗菌能力的情况下对降低毒性起着关键作用，Nigrocin-PN可能是一种理想的治疗候选物。
