Internalization and membrane activity of the antimicrobial peptide CGA-N12

作者：Ruifang Li, Mengke Tao, Li Shang, Xueqin Wang, Yanhui Yang, Lianfeng Mo, Kaidi Zhang, Ao Wei, Liang Huang · 发表于：Biochemical Journal · 年份：2021 · DOI：10.1042/bcj20201006 · 被引用次数：4 · 研究领域：Antimicrobial Peptides and Activities、Biochemical and Structural Characterization、Polydiacetylene-based materials and applications

Antimicrobial peptides (AMPs) are conventional antibiotic alternatives due to their broad-spectrum antimicrobial activities and special mechanisms of action against pathogens. The antifungal peptide CGA-N12 was originally derived from human chromogranin A (CGA) and consists of the 65th to 76th amino acids of the CGA N-terminal region. In the present study, we found that CGA-N12 had fungicidal activity and exhibited time-dependent inhibition activity against Candida tropicalis. CGA-N12 entered the cells to exert its antagonist activity. The internalization of CGA-N12 was energy-dependent and accompanied by actin cytoskeleton-, clathrin-, sulfate proteoglycan-, endosome-, and lipid-depleting agent-mediated endocytosis. Moreover, the CGA-N12 internalization pathway was related to the peptide concentration. The effects of CGA-N12 on the cell membrane were investigated. CGA-N12 at a low concentration less than 4 × MIC100 did not destroy the cell membrane. While with increasing concentration, the damage to the cell membrane caused by CGA-N12 became more serious. At concentrations greater than 4 × MIC100, CGA-N12 destroyed the cell membrane integrity. Therefore, the membrane activity of CGA-N12 is concentration dependant.