Meyer Julie L, Paul Valerie J, Teplitski Max
Soil and Water Science Department, University of Florida-Institute of Food and Agricultural Sciences, Gainesville, Florida, United States of America.
Smithsonian Marine Station, Ft. Pierce, Florida, United States of America.
PLoS One. 2014 Jun 17;9(6):e100316. doi: 10.1371/journal.pone.0100316. eCollection 2014.
Apical lesions on Porites astreoides were characterized by the appearance of a thin yellow band, which was preceded by bleaching of the coral tissues and followed by a completely denuded coral skeleton, which often harbored secondary macroalgal colonizers. These characteristics have not been previously described in Porites and do not match common Caribbean coral diseases. The lesions were observed only in warmer months and at shallow depths on the fore reef in Belize. Analysis of the microbial community composition based on the V4 hypervariable region of 16S ribosomal RNA genes revealed that the surface microbiomes associated with nonsymptomatic corals were dominated by the members of the genus Endozoicomonas, consistent with other studies. Comparison of the microbiomes of nonsymptomatic and lesioned coral colonies sampled in July and September revealed two distinct groups, inconsistently related to the disease state of the coral, but showing some temporal signal. The loss of Endozoicomonas was characteristic of lesioned corals, which also harbored potential opportunistic pathogens such as Alternaria, Stenotrophomonas, and Achromobacter. The presence of lesions in P. astreoides coincided with a decrease in the relative abundance of Endozoicomonas, rather than the appearance of specific pathogenic taxa.
多孔鹿角珊瑚（Porites astreoides）的顶端病变特征为出现一条细的黄色带，在此之前珊瑚组织会发生白化，之后珊瑚骨骼完全裸露，且骨骼上常常附着有次生大型藻类殖民者。这些特征此前在多孔鹿角珊瑚中未曾描述过，也不符合常见的加勒比珊瑚疾病。这些病变仅在温暖月份以及伯利兹堡礁浅水区被观察到。基于16S核糖体RNA基因的V4高变区对微生物群落组成进行分析发现，与无症状珊瑚相关的表面微生物群以内共生单胞菌属（Endozoicomonas）成员为主，这与其他研究结果一致。对7月和9月采集的无症状和患病珊瑚群体的微生物群进行比较，发现了两个不同的组，它们与珊瑚的疾病状态没有一致的关联，但显示出一些时间信号。内共生单胞菌的减少是患病珊瑚的特征，患病珊瑚还含有潜在的机会性病原体，如链格孢属（Alternaria）、嗜麦芽窄食单胞菌（Stenotrophomonas）和无色杆菌属（Achromobacter）。多孔鹿角珊瑚中病变的出现与内共生单胞菌相对丰度的降低相吻合，而不是特定致病类群的出现。
