Cold Adaptations of Carbon Metabolism in Antarctic Phototrophic Microorganisms

生物冷适应的分子机制研究 系统对于理解进化和 地球上物种的生态互动。 干旱河谷 在南极洲的一个地区，一个完整的微生物生态系统生活在 砂岩在冻结温度和永久冰覆盖 湖泊. 维斯塔尔建议确定嗜冷性 光养生物（冷适应蓝藻，藻类和光合 细菌）具有独特的核苷酸和氨基酸序列， 它们的DNA和光合作用中一种关键的二氧化碳固定酶， 酶在零度以下的功能。 从 以前的奖项（探索性研究小额赠款），维斯塔尔 确定这种来自嗜冷蓝藻的关键酶 具有独特的光合作用特性，这可能与其 这种二氧化碳固定酶的分子结构。 使用 分子生物学的最新方法，真正的嗜冷 光养生物，这将有选择地从砂岩中分离出来， 将对来自干谷湖泊的藻垫进行研究。 如果这些 南极嗜冷生物的DNA序列独特， 酶，这些信息将提供新的见解， 生物的冷适应机制及其 与其他温带物种的进化关系。

Studying the molecular mechanisms of cold-adaptation of biological systems is intrinsically important to understand evolution and ecological interaction of species on Earth. In the Dry Valley region of Antarctica, a complete microbial ecosystem lives within sandstone at freezing temperatures and in permanently ice-covered lakes. Vestal proposes to determine whether psychrophilic phototrophs (cold-adapted cyanobacteria, algae, and photosynthetic bacteria) possess unique nucleotides and amino acids sequences in their DNA and a key CO2-fixing enzyme in photosynthesis to account for the enzyme's function at sub-zero temperatures. From a previous award (Small Grant for Exploratory Research), Vestal determined that this key enzyme from a psychrophilic cyanobacterium has unique photosynthetic properties that may be related to its molecular structure of this particular CO2-fixing enzyme. Using the latest methods of molecular biology, true psychrophilic phototrophs, which will be selectively isolated from sandstone and algal mats from Dry Valley lakes, will be studied. If these Antarctic psychrophiles possess unique sequences in their DNA and enzymes, the information would provide new insight into the mechanism of cold-adaptation of biological species and their evolutionary relatedness to other temperate species.