Diversity and Ecology of Bdellovibrios-like Organisms in Nature

该项目的目标是确定水生环境中类蛭弧菌(BLO)的多样性范围和作用。我们的具体目标是：1)揭示和表征自然界中捕食性类蛭弧菌(BLO)的遗传、文化和生理多样性，并显示菌株多样性与猎物范围之间的相关性；2)揭示BLO的主要未培养和培养菌株，这些菌株最有可能对自然界中的细菌死亡做出最大贡献，并显示它们在水生生态系统中的时空分布；以及3)监测浮游植物/细菌水华中BLO的种群动态，并评估它们在细菌死亡中的潜在作用。将分析培养的和未培养的BLO的遗传多样性。最初的工作将是完成对目前在实验室中的50个菌株的多样性分析，这些菌株是从从美国和国外的湖泊、海洋、池塘和溪流采集的水样中提取的。将对样本进行处理，以检测培养的和未培养的BLO。未培养的生物体将通过使用BLO特异性寡核苷酸探针的分子技术进行鉴定。培养的菌株将使用双琼脂覆盖技术进行回收。特别是，我们将采样以确定在上升流刺激的水华期间，BLO群落与LEO？15站点(位于罗格斯大学海洋野外站近海大陆架的长期生态系统观测站)浮游植物水华的潜在相互作用。这项工作将与新泽西州立大学罗格斯海洋和海岸科学研究所的Lee Kerkhof博士合作完成。

The goal of this project is to determine the range in diversity and role of the bdellovibrio-like organisms (BLOs) in aquatic environments. Our specific aims are: 1) to reveal and characterize the genetic, cultural and physiological diversity of the predatory, bdellovibrio?like organisms (BLOs) in nature and to show a correlation between strain diversity and prey range; 2) to reveal the predominant uncultured and cultured strains of BLO, those most likely making the greatest contribution to bacterial mortality in nature, and show their spatial and temporal distribution in aquatic ecosystems; and 3) to monitor the population dynamics of BLO in phytoplankton/ bacterial blooms and assess their potential role in bacterial mortality. Genetic diversity will be analyzed for both cultured and uncultured BLOs. The initial effort will be to complete the diversity analysis on the 50 strains currently in the laboratory that have been recovered from water samples collected from lakes, oceans, seas, ponds and streams in the United States and abroad. Samples will be processed to detect both cultured and uncultured BLOs. The uncultured organisms will be identified by using molecular techniques employing BLO?specific oligonucleotide probes. The cultured strains will be recovered using the double agar overlay technique. In particular, we will sample to determine the potential interaction of the BLO community with phytoplankton blooms at the LEO? 15 site (a Long?Term Ecosystem Observatory site on the continental shelf offshore from the Rutgers University Marine Field Station) during upwelling-stimulated blooms. This work will be done in collaboration with Dr. Lee Kerkhof at the Institute of Marine and Coastal Sciences at Rutgers, the State University of New Jersey.