Australian Institute of Marine Science, Townsville, Qld, Australia School of Marine and Tropical Biology, James Cook University, Townsville, Qld, Australia AIMS@JCU, Townsville, Qld 4811, Australia ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Qld, Australia.
Environ Microbiol Rep. 2011 Dec;3(6):651-60. doi: 10.1111/j.1758-2229.2010.00234.x. Epub 2011 Jan 10.
Understanding the effects of elevated seawater temperatures on each member of the coral holobiont (the complex comprised of coral polyps and associated symbiotic microorganisms, including Bacteria, viruses, Fungi, Archaea and endolithic algae) is becoming increasingly important as evidence accumulates that microbial members contribute to overall coral health, particularly during thermal stress. Here we use a metagenomic approach to identify metabolic and taxonomic shifts in microbial communities associated with the hard coral Acropora millepora throughout a natural thermal bleaching event at Magnetic Island (Great Barrier Reef). A direct comparison of metagenomic data sets from healthy versus bleached corals indicated major shifts in microbial associates during heat stress, including Bacteria, Archaea, viruses, Fungi and micro-algae. Overall, metabolism of the microbial community shifted from autotrophy to heterotrophy, including increases in genes associated with the metabolism of fatty acids, proteins, simple carbohydrates, phosphorus and sulfur. In addition, the proportion of virulence genes was higher in the bleached library, indicating an increase in microorganisms capable of pathogenesis following bleaching. These results demonstrate that thermal stress results in shifts in coral-associated microbial communities that may lead to deteriorating coral health.
了解海水温度升高对珊瑚共生体（由珊瑚虫和相关共生微生物组成，包括细菌、病毒、真菌、古菌和内生藻类）每个成员的影响变得越来越重要，因为越来越多的证据表明微生物成员对整体珊瑚健康有贡献，尤其是在热应激期间。在这里，我们使用宏基因组学方法来鉴定与硬珊瑚 Acropora millepora 相关的微生物群落在 Magnetic Island（大堡礁）自然热白化事件期间的代谢和分类变化。对健康珊瑚和白化珊瑚的宏基因组数据集进行直接比较表明，在热应激期间微生物伴侣发生了重大变化，包括细菌、古菌、病毒、真菌和微藻。总的来说，微生物群落的代谢从自养转变为异养，包括与脂肪酸、蛋白质、简单碳水化合物、磷和硫代谢相关的基因增加。此外，在白化文库中，毒力基因的比例更高，表明在白化后，能够引起发病的微生物数量增加。这些结果表明，热应激导致珊瑚相关微生物群落的变化，可能导致珊瑚健康状况恶化。
