Comparative functional biodiversity of Antarctic and Arctic Sea Ice Communities

该项目的目的是使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，并将结果与从南极海冰样品中获得的相应数据进行比较。就其非生物限制而言，海冰似乎是一个不利的栖息地。尽管条件恶劣，但微生物大量繁殖，构成了具有全球意义的生态系统。在这里，我们建议通过生成环境18s rDNA文库来描述选定海冰群落的分子生物多样性，帮助我们解开未知或不可培养物种的身份（“隐藏的生物多样性”）。我们还旨在确定真核海冰生物的转录输入生态系统功能随机测序环境cDNA样本。使用最近开发的系统发育工具，我们将确定功能和系统发育的ESTs的隶属关系，并以链接海冰生物多样性与转录活性的主要群体和选定的基因组和宏基因组。我们还打算将生物多样性和转录活性与原位测量的物理和生化参数相关联。最后，我们将比较南极和北极海冰的功能生物多样性。由于嗜冷微生物对极端生境具有独特的生理适应性，它们是应用科学的潜在研究对象。

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.