Pereira Letícia B, Palermo Bruna R Z, Carlos Camila, Ottoboni Laura M M
Center for Molecular Biology and Genetic Engineering (CBMEG), State University of Campinas - UNICAMP, CP 6010, Campinas, S.P., Brazil.
FEMS Microbiol Lett. 2017 Sep 1;364(16). doi: 10.1093/femsle/fnx164.
Corals harbor a wide diversity of bacteria associated with their mucus. These bacteria can play an important role in nutrient cycling, degradation of xenobiotics and defense against pathogens by producing antimicrobial compounds. However, the diversity of the cultivable heterotrophic bacteria, especially in the Brazilian coral species, remains poorly understood. The present work compares the diversity of cultivable bacteria isolated from the mucus and surrounding environments of four coral species present along the Brazilian coast, and explores the antibacterial activity of these bacteria. Bacteria belonging to the phyla Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes were isolated. The mucus environment presented a significantly different bacteria composition, compared to the water and sediment environments, with high abundance of Alcanivorax, Acinetobacter, Aurantimonas and Erythrobacter. No difference in the inhibition activity was found between the isolates from mucus and from the surrounding environment. Eighty-three per cent of the bacteria isolated from the mucus presented antimicrobial activity against Serratia marcescens, an opportunistic coral pathogen, suggesting that they might play a role in maintaining the health of the host. Most of the bacteria isolates that presented positive antimicrobial activity belonged to the genus Bacillus.
珊瑚的黏液中栖息着种类繁多的细菌。这些细菌在营养物质循环、外源性物质降解以及通过产生抗菌化合物抵御病原体方面发挥着重要作用。然而，可培养的异养细菌的多样性，尤其是巴西珊瑚物种中的多样性，仍然知之甚少。本研究比较了从巴西海岸沿线四种珊瑚物种的黏液及其周围环境中分离出的可培养细菌的多样性，并探究了这些细菌的抗菌活性。分离出了属于变形菌门、厚壁菌门、放线菌门和拟杆菌门的细菌。与水和沉积物环境相比，黏液环境呈现出显著不同的细菌组成，其中Alcanivorax、不动杆菌属、橙色单胞菌属和红杆菌属的丰度较高。从黏液中分离出的菌株与从周围环境中分离出的菌株在抑制活性方面没有差异。从黏液中分离出的细菌中有83%对珊瑚机会致病菌粘质沙雷氏菌具有抗菌活性，这表明它们可能在维持宿主健康方面发挥作用。大多数呈现出阳性抗菌活性的细菌分离株属于芽孢杆菌属。
