Temperature recorded in DNA and soft-tissue biomass: Implications for the deep-sea biosphere

该奖项是根据2009年美国复苏和再投资法案(公法111-5)资助的。这是一项潜在的变革性研究，重点是DNA中磷酸盐中的氧同位素比率是否记录了生物体生长的温度。它的目的是探索古代和现代极端环境中生命的环境条件和最适温度。该方法使用受控实验室实验，其中微生物和有限数量的模式大型动物，如斑马鱼，在广泛的温度范围内进行培养/生长。微生物研究将在已知生长温度范围的物种的纯培养上进行。还将考察生长速度、营养限制、pH和磷酸盐吸收速率对DNA中磷酸盐氧同位素比率的温度依赖性的影响。此外，这项工作将通过分析从温泉和深海热液喷口等极端高温环境中收集的微型和大型生物的自然样本，来测试DNA和生物量同位素温度记录的稳健性。由于DNA是所有生命的基本单位，这项工作将提供对其温度记录特性的深入了解，这可能对确定生命的温度上限具有深远影响，并将揭示地球和其他行星上生命存在的环境。这项工作的更广泛的影响是重大的，包括从高中到博士后水平的研究和教育的完全整合，对学生的支持，以及对来自科学界代表性不足群体的两名研究人员的支持。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).This is potentially transformative research that focuses on whether the oxygen isotope ratios in phosphate in DNA record the temperature at which organisms grow. Its purpose is to explore the environmental conditions and temperature optima for life in ancient and modern extreme environments. The approach uses controlled laboratory experiments in which microbes and a limited number of model macrofauna, such as zebra fish, are cultured/grown over a wide range of temperatures. Microbial studies will be done on pure cultures of species with known growth temperature ranges. The impacts of growth rate, nutrient limitation, pH, and phosphate uptake rate on the temperature dependence of the oxygen isotope ratio of phosphate in DNA will also be examined. In addition the work will test the robustness of the DNA and biomass isotope temperature record by analyzing natural samples of micro-and macro-organisms collected from thermally extreme environments such as hot springs and deep-sea hydrothermal vents. Because DNA is a fundamental unit of all life, this work will provide a robust understanding of its temperature-recording properties which could have far-reaching implications for determining the upper temperature limit for life and will shed light on environments in which life can exist on Earth and other planets. Broader impacts of the work are significant and include complete integration of research and education from the high school to the postdoctoral level, support of students, and support of two researchers who are from groups under-represented in the sciences.