Bhedi Chinmayee D, Prevatte Carson W, Lookadoo Maggie S, Waikel Patricia A, Gillevet Patrick M, Sikaroodi Masoumeh, Campagna Shawn R, Richardson Laurie L
Department of Biological Sciences, Florida International University, Miami, FL 33199, USA.
Department of Chemistry, University of Tennessee, Knoxville, TN 37996, USA.
FEMS Microbiol Ecol. 2017 Mar 1;93(3). doi: 10.1093/femsec/fix005.
Black band disease (BBD) of corals is a horizontally migrating, pathogenic, polymicrobial mat community which is active above a temperature threshold of 27.5°C on the reef. Bacterial isolates from BBD, the surface mucopolysaccharide layer (SML) of healthy corals and SML of healthy areas of BBD-infected corals were tested for production of short- to medium-chain acyl homoserine lactones (AHLs) using the Chromobacterium violaceum CV026 reporter strain. Of 110 bacterial isolates tested, 19 produced AHLs and 15 of these were from BBD. Eight AHLs were identified using LC-MS/MS, with 3OHC4 the most commonly produced, followed by C6. AHL-producing isolates exposed to three temperatures (24°C, 27°C, 30°C) revealed that production of three AHLs (3OHC4, 3OHC5 and 3OHC6) significantly increased at 30°C when compared to 24°C. 16S rRNA gene sequencing revealed that all of the AHL-producing BBD isolates were vibrios. Metagenomic data of BBD communities showed the presence of AHL (and autoinducer-2) genes, many of which are known to be associated with vibrios. These findings suggest that quorum sensing may be involved in BBD pathobiology and community structure due to enhanced production of quorum-sensing signal molecules (AHLs) above the temperature threshold of this globally distributed coral disease.
珊瑚的黑带病（BBD）是一种水平迁移的、致病性的、多微生物垫群落，在珊瑚礁上温度阈值为27.5°C以上时活跃。使用紫色杆菌CV026报告菌株对来自黑带病的细菌分离株、健康珊瑚的表面粘多糖层（SML）以及黑带病感染珊瑚健康区域的SML进行了短链至中链酰基高丝氨酸内酯（AHLs）产生情况的测试。在测试的110个细菌分离株中，19个产生AHLs，其中15个来自黑带病。使用液相色谱-串联质谱法（LC-MS/MS）鉴定出8种AHLs，其中3OHC4产生最为常见，其次是C6。将产生AHLs的分离株置于三个温度（24°C、27°C、30°C）下，结果显示与24°C相比，30°C时三种AHLs（3OHC4、3OHC5和3OHC6）的产生显著增加。16S rRNA基因测序表明，所有产生AHLs的黑带病分离株均为弧菌。黑带病群落的宏基因组数据显示存在AHL（和自诱导物-2）基因，其中许多已知与弧菌有关。这些发现表明，由于在这种全球分布的珊瑚疾病的温度阈值以上群体感应信号分子（AHLs）的产生增加，群体感应可能参与了黑带病的病理生物学和群落结构。
