Stomatology Department, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.
State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, Chengdu, China.
J Appl Microbiol. 2022 Aug;133(2):1052-1062. doi: 10.1111/jam.15614. Epub 2022 May 29.
Accumulating evidence suggests that Porphyromonas gingivalis is closely associated with the development of various chronic inflammatory diseases, particularly periodontitis. This study investigated the antibacterial activity and action mechanism of a novel antimicrobial peptide (AMP), DP7, against P. gingivalis.
The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for DP7 were determined via a broth microdilution method, revealing an MIC of 8 μg ml and MBC of 32 μg ml . Growth inhibition and killing assays confirmed the bactericidal effect of DP7, and treatment with DP7 at MBC eliminated P. gingivalis within 8 h. DP7 had a low cytotoxic effect against human cells. Transmission electron microscopy revealed that DP7 destroyed the bacterial membrane, and confocal laser scanning microscopy revealed its inhibitory effect on P. gingivalis biofilms. Quantitative reverse transcription-polymerase chain reaction revealed DP7-mediated inhibition of several virulence factor genes, partially explaining its antibacterial mechanism.
DP7, a novel AMP with low mammalian cytotoxicity, inhibits both planktonic and biofilm forms of P. gingivalis by destroying the bacterial membrane and reducing virulence factor gene expression.
DP7 has potential clinical application in the prevention and treatment of P. gingivalis-associated diseases.
越来越多的证据表明，牙龈卟啉单胞菌与各种慢性炎症性疾病的发展密切相关，特别是牙周炎。本研究旨在探讨一种新型抗菌肽（AMP）DP7 对牙龈卟啉单胞菌的抗菌活性及其作用机制。
采用肉汤微量稀释法测定 DP7 的最小抑菌浓度（MIC）和最小杀菌浓度（MBC），结果显示 DP7 的 MIC 为 8μg/ml，MBC 为 32μg/ml。生长抑制和杀菌实验证实了 DP7 的杀菌作用，MBC 浓度的 DP7 处理可在 8h 内消除牙龈卟啉单胞菌。DP7 对人细胞的细胞毒性较低。透射电子显微镜显示 DP7 破坏了细菌膜，共聚焦激光扫描显微镜显示其对牙龈卟啉单胞菌生物膜具有抑制作用。定量逆转录聚合酶链反应显示 DP7 介导的几种毒力因子基因抑制作用，部分解释了其抗菌机制。
DP7 是一种具有低哺乳动物细胞毒性的新型 AMP，通过破坏细菌膜和降低毒力因子基因表达来抑制浮游和生物膜形式的牙龈卟啉单胞菌。
DP7 具有预防和治疗牙龈卟啉单胞菌相关疾病的潜在临床应用价值。
