Microbial Observatory: Metabolic Activity of Microorganisms in Alaskan Tundra and Permafrost

一笔赠款已授予尼古拉S。Panikov（新泽西州史蒂文斯理工学院）和弗拉基米尔罗曼诺夫斯基（阿拉斯加大学费尔班克斯）在阿拉斯加苔原建立微生物观测站项目。长期的挑战是确定、表征和监测在冻土中活跃的嗜冷（超冷）微生物，这些微生物可能是最近发现的北极冬季大量二氧化碳排放的原因。这个为期2年的“概念验证”项目的具体目标是提出令人信服的证据，证明这种微生物存在，并可以通过分离和培养独立的分子技术相结合进行研究。在实验室培养研究中，将根据碳掺入细胞和细胞成分（DNA、磷脂）的原位速率评估嗜冷微生物的生长和活性。各种基材、温度的测试（0至-40 ° C）和其他生长条件下，研究人员将能够开发出微生物富集的优化方案，并分离出冻土中生长的微生物的13 C同位素富集DNA。阿拉斯加冻土被发现是最近全球气候变化的重要触发因素：气候变暖导致了永久冻土层的退化，并刺激了微生物的分解，使冻土带从一个“汇”变成了一个净碳源。对观测到的气候和大气变化的理解、预测和减缓，关键取决于对冻土微生物学的了解。该研究的更广泛影响包括更可靠的气候预测，对超冷温度下其他行星上生命的洞察，以及在低于冰点温度下发挥作用的高效生物催化剂的开发。为了便利传播有关这一令人兴奋的努力的信息，将为该项目建立一个网站。

A grant has been awarded to Drs. Nicolai S. Panikov (Stevens Institute of Technology, NJ) and Vladimir Romanovsky (University of Alaska Fairbanks) to establish a Microbial Observatory project in the Alaskan tundra. The long-term challenge is to identify, characterize and monitor over time and space the psychrophilic (ultracold-loving) microorganisms active in frozen ground likely to be responsible for recently discovered sizeable winter CO2 emissions in the Arctic. The particular goal of this 2-year 'proof-of-concept' project is to present convincing evidence that such microorganisms exist and can be studied by a combination of isolation and culture-independent molecular techniques. Growth and activity of psychrophilic microorganisms will be assessed from the in situ rates of carbon incorporation into cells and cellular constituents (DNA, phospholipids) in laboratory incubation studies. Testing of various substrates, temperatures (from 0 to -40 oC) and other growth conditions will allow the investigators to develop an optimized protocol for microbial enrichment, and to isolate 13C isotope-enriched DNA of microorganisms growing in frozen soil.Alaskan tundra was found to be an important trigger in recent global climatic changes: warming caused degradation of permafrost and stimulated microbial decomposition, converting the tundra from a 'sink' to a net source of carbon. The understanding, prediction and mitigation of the observed climate and atmospheric changes critically depend on knowledge of permafrost microbiology. Broader impacts of the research include more reliable climate predictions, insights into life on other planets under ultracold temperatures and development of highly efficient biocatalysts functioning at below freezing temperatures. To facilitate dissemination of information about this exciting effort, a web site will be established for the project.