从鱼类中鉴定出的β-防御素是一类重要的抗菌肽，对于对抗细菌性鱼类病原体非常重要。本研究的重点是 CsDef 的分子和功能表征，CsDef 是一种源自黑鳢 (Channa striata) 的 63 个氨基酸 β-防御素抗菌肽。 CsDef 的理化属性与 AMP 中观察到的独特特征一致。 CsDef 是重组生产的，重组肽 rCsDef 对细菌性鱼类病原体表现出显着的抗菌功效，对解蛋白弧菌的 MIC 为 16 μM。在 32 μM rCsDef 条件下，A. Hydrophila 的抑制率为 91%，E. tarda 的抑制率为 92%，V. harveyi 的抑制率为 53%。 rCsDef 表现出多方面的抗细菌作用机制，即通过膜去极化、膜透化和产生 ROS。 rCsDef 对 hRBC 无溶血作用，对正常哺乳动物细胞系 CHO-K1 无细胞毒性。然而，它在 MCF-7 中表现出抗癌特性。 rCsDef 在 pH、温度、盐、金属离子和蛋白酶方面表现出显着的稳定性。这些发现表明它是水产养殖中潜在应用的潜在候选分子。© 2024。作者获得 Springer Science Business Media, LLC（Springer Nature 旗下公司）的独家许可。

Beta-defensins, identified from fishes, constitute a crucial category of antimicrobial peptides important in combating bacterial fish pathogens. The present investigation centers on the molecular and functional characterization of CsDef, a 63-amino acid beta-defensin antimicrobial peptide derived from snakehead murrel (Channa striata). The physicochemical attributes of CsDef align with the distinctive characteristics observed in AMPs. CsDef was recombinantly produced, and the recombinant peptide, rCsDef, exhibited notable antibacterial efficacy against bacterial fish pathogens with an MIC of 16 μM for V. proteolyticus. A. hydrophila exhibited 91% inhibition, E. tarda 92%, and V. harveyi 53% at 32 μM of rCsDef. The rCsDef exhibited a multifaceted mechanism of action against bacteria, i.e., through membrane depolarization, membrane permeabilization, and generation of ROS. The rCsDef was non-hemolytic to hRBCs and non-cytotoxic to normal mammalian cell line CHO-K1. However, it exhibited anticancer properties in MCF-7. rCsDef demonstrated notable stability with respect to pH, temperature, salt, metal ions, and proteases. These findings suggest it is a potential candidate molecule for prospective applications in aquaculture.© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.