LEXEN: Protistan Biodiversity in Antarctic Marine Ecosystems: Molecular Biological and Traditional Approaches

LEXEN：南极海洋生态系统中的原生生物多样性：分子生物学和传统方法

• 批准号: 9714299
• 负责人: David Caron
• 金额: $ 35万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-15 至 2002-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9714299&HistoricalAwards=false
• 关键词: LEXEN; Protistan; Biodiversity; Antarctic; Marine

*** Caron 9714299 The analysis of microbial biodiversity of extreme environments is difficult because traditional methods for examining diversity are often ineffective for assessing species richness within these communities. Additional difficulties arise due to the difficulties of recreating and maintaining pertinent environmental features during sample collection and procession. This study focuses on the protistan assemblages (algae and protozoa) in the sea ice, sediment and ocean environments of the Ross Sea, Antarctica. The identification of protistan species in natural assemblages traditionally has entailed direct microscopical analyses as well as enrichment and culture techniques for assessing biodiversity. Determination of diversity for these assemblages in therefore susceptible to biases as a consequence of sampling, enrichment and culture, as well as selective losses due to sample preservation and concentration for microscopy. The goals of this project are: (1) to develop and apply molecular biological approaches to assess species diversity of small protists (algae and protozoa smaller than 100 micrometers) in ocean water, sea ice and sediment environments and (2) to obtain baseline physiological information on the growth rates, feeding rates and growth efficiencies of cultured protozoa under pertinent temperature regimes. Molecular biological studies will involve the use of PCR-based protocols to examine small subunit ribosomal RNA gene (srDNA) diversity. Approaches and techniques developed will be applicable to any other water body or sediment and would provide a means to examine the representativeness of protistan cultures in extant culture collections. ***

*** Caron 9714299极端环境的微生物生物多样性的分析很困难，因为检查多样性的传统方法通常无法评估这些社区内的物种丰富度。由于在样本收集和游行过程中，重新创建和维持相关环境特征的困难导致了其他困难。这项研究的重点是南极洲罗斯海的海冰，沉积物和海洋环境中的Protistan组合（藻类和原生动物）。 传统上，自然组合中原生类物种的鉴定需要直接的显微镜分析，以及评估生物多样性的富集和培养技术。因此，由于采样，富集和培养以及由于显微镜的样品保存和浓度而导致的选择性损失，因此在偏见的情况下确定了这些组合的多样性。该项目的目标是：（1）开发和应用分子生物学方法，以评估海洋水，海冰和沉积物环境中的小生物（藻类和原生动物小于100微米）的物种多样性，以及（2）以在培养的原生动体温度方面的生长速率，进食率和生长率，以获取基线生理信息。分子生物学研究将涉及使用基于PCR的方案来检查小型亚基核糖体RNA基因（SRDNA）多样性。开发的方法和技术将适用于任何其他水体或沉积物，并将提供一种检查在现存的文化收藏中prodistan培养物的代表性的方法。 ***