本研究旨在调查越南芽庄湾白化和健康的滨珊瑚之间的珊瑚表面粘液层 (SML) 的生物活性如何响应粘液相关细菌群落的变化。研究结果表明，粘液相关细菌群落的显着变化与珊瑚健康状态从白化到健康的 P. lobata 菌落的变化有关 (p<0.05)，而细菌组成在不同季节和地点之间没有显着差异 (p>0.05) ）。其中希瓦氏菌属、梭杆菌属、卤脱硫弧菌属、Marinifilum属、内生单胞菌属、Litoribacillus属、藻类属和弧菌属等8个属仅存在于白化珊瑚的SML中，而在健康珊瑚的SML中不存在。与漂白的 SML 相比，健康的 SML 对珊瑚漂白病原体 V. Coralliilyticus 表现出更强的抗菌活性，对 HCT116 细胞具有更高的抗肿瘤活性，同时增加了裂解 PARP 的诱导，加速了细胞核凋亡和 S 和 G2/ 周期停滞。 M 期表现出几个典型特征：细胞皱缩、细胞接触丧失和凋亡体形成。此外，在健康 SML 中在 280 nm 处检测到的假定化合物明显高于漂白 SML 中的化合物，它们可能是负责从健康 SML 中竞争性排除病原体、阿尔吉科拉 (Algicola) 和弧菌 (Vibrio) 的生物活性分子。版权所有 © 2024。 出版者爱思唯尔公司

This study aims to investigate how bioactivities of the coral surface mucus layer (SML) respond to changes in mucus-associated bacterial communities between bleached and healthy Porites lobata corals in Nha Trang Bay, Vietnam. The findings suggested that significant shift in the mucus-associated bacterial communities were related to changes in coral health states from bleached to healthy P. lobata colonies (p < 0.05), while bacterial compositions were not significantly different across seasons and locations (p > 0.05). Of which 8 genera, Shewanella, Fusibacter, Halodesulfovibrio, Marinifilum, Endozoicomonas, Litoribacillus, Algicola, and Vibrio were present only in the SML of bleached coral while absent in the SML of healthy one. As compared with the bleached SML, the healthy SML demonstrated stronger antibacterial activity against a coral bleaching pathogen, V. coralliilyticus, higher antitumor activity against HCT116 cell accompanied with increased induction of cleaved PARP and accelerated cell nucleic apoptosis and cycle arrest at S and G2/M phases exhibiting several typical characteristics, cell shrinkage, lost cell contact, and apoptotic body formation. Moreover, putative compounds detected at 280 nm in the healthy SML were obviously higher than those in the bleached one, probably they could be bioactive molecules responsible for competitively exclusion of pathogens, Algicola and Vibrio, from the healthy SML.Copyright © 2024. Published by Elsevier Inc.