Comparative functional biodiversity of Antarctic and Arctic Sea Ice Communities

该项目的目的是利用系统发育方法确定北极海冰样品中的真核生物多样性和转录活性，并将结果与南极海冰样品中获得的相应数据进行比较。由于受到非生物的限制，海冰似乎是一个充满敌意的栖息地。尽管条件恶劣，但微生物大量存在，构成了一个具有全球意义的生态系统。在这里，我们建议通过建立环境18s rDNA文库来描述选定海冰群落的分子生物多样性，帮助我们揭示未知或不可培养物种的身份（“隐藏的生物多样性”）。我们还旨在通过随机测序环境cDNA样本来确定真核海冰生物对生态系统功能的转录输入。利用最近开发的系统发育工具，我们将确定est的功能和系统发育关系，以便将海冰生物多样性与主要群体和选定基因组和宏基因组的转录活性联系起来。我们进一步打算将生物多样性和转录活性与采样期间测量的原位物理和生化参数联系起来。最后，我们将比较南极和北极海冰的功能生物多样性。由于嗜冷微生物对其极端栖息地具有独特的生理适应性，因此它们可能是应用科学研究的有趣对象。

The aim of this project is to determine the eukaryotic biodiversity and transcriptional activity in Arctic sea ice samples using phylogenetic approaches, and to compare the results to respective data obtained from Antarctic sea ice samples. Sea ice is a seemingly hostile habitat with regard to its abiotic constraints. Despite these harsh conditions it is heavily populated by microbial organisms, constituting an ecosystem of global significance. Here we propose to describe the molecular biodiversity of selected sea ice communities by generating environmental 18s rDNA libraries, helping us to unravel the identity of unknown or unculturable species („hidden biodiversity"). We also aim for determining the transcriptional input of eukaryotic sea ice organisms to ecosystem functioning by randomly sequencing environmental cDNA samples. Using recently developed phylogenetic tools we will determine function and phylogenetic affiliation of ESTs and on order to link sea ice biodiversity with transcriptional activity of major groups and selected genomes and metagenomes. We further intend to correlate biodiversity and transcriptional activity with in situ physical and biochemical parameters measured during.sampling. Finally we will compare the functional biodiversity in Antarctic versus Arctic sea ice. Since psychrophilic microorganisms possess unique physiological adaptations to their extreme habitat, they are potentially interesting objects for applied science.