LEXEN: Biogenic Fractionations of Transition Metal Isotopes: Novel Methods for the Examination of Life in Extreme Environments

Ariel D. Anbar和Kenneth H. Nealson，来自美国司法部， 罗切斯特大学的地球与环境科学系 由化学部，多学科办公室 数学和物理科学理事会的活动， 生物科学局和地球科学处 过渡金属的生物分馏研究 同位素 这些研究验证了稳定的分馏 关键代谢金属的同位素发生在吸收和代谢过程中， 这些金属通过微生物和这种同位素分馏将 留下一个可识别的特征，这将有助于研究生命 在极端条件下无法应用 其他生物标志物。 Anbar和Nealson教授使用多收集器 电感耦合等离子体质谱法来表征同位素 从现场取样的微生物中分离的金属成分 以及在受控的实验室条件下培养的微生物。 他们的 研究的重点是同位素的动力学分馏 铜和锌，预计在酶催化吸收这些 金属和铁，预期在微生物介导的氧化还原过程中 反应. 这些生物同位素分馏有望提供 关于存在或不存在生物活性的信息， 特别是关于特定的代谢过程。 碳、氮和硫的稳定同位素的分馏， 含有不同同位素的化合物的不同反应速率 多年来，这些元素被用来获取有关 无法直接观察的环境中的代谢过程。 在化学司的支持下， 数学和物理科学的多学科活动 理事会、生物科学理事会和 地球科学教授Ariel D. Anbar和Kenneth H.尼尔逊， 加拿大多伦多大学地球与环境科学系 罗切斯特正在开发技术来探索生物源 在代谢中起关键作用的金属同位素的分馏 流程. 通过分析铜、锌、 和铁，Anbar教授和Nealson教授获得了关于 存在或不存在一般生物活性和特定生物活性 尤其是代谢过程。 这些研究特别 研究极端环境下的生命的实用工具， 条件排除了其他“生物标志物”的应用。 等 环境包括物理上远程的现代设置， 受到极端环境条件和古老环境的影响 只能通过地质记录来研究。

Professors Ariel D. Anbar and Kenneth H. Nealson, of the Department of Earth and Environmental Sciences at the University of Rochester, are supported by the Division of Chemistry, the Office of Multidisciplinary Activities of the Mathematical and Physical Sciences Directorate, the Directorate for Biological Sciences, and the Division of Earth Sciences for their studies of the biogenic fractionation of transition metal isotopes. These studies test the hypothesis that fractionation of stable isotopes of key metabolic metals occurs during uptake and metabolism of these metals by microorganisms and that such isotope fractionation will leave a recognizable signature that will be useful for the study of life in environments where extreme conditions preclude the application of other biomarkers. Professors Anbar and Nealson use multiple-collector inductively-coupled plasma mass spectrometry to characterize the isotopic compositions of metals isolated from microorganisms sampled in the field and from microbes cultured under controlled laboratory conditions. Their studies are focused on the kinetic fractionation of the isotopes of copper and zinc, expected during the enzyme-catalyzed uptake of these metals, and of iron, expected during microbially-mediated redox reactions. These biogenic isotope fractionations are expected to provide information about the presence or absence of biological activity in general and about specific metabolic processes in particular. Fractionation of stable isotopes of carbon, nitrogen, and sulfur due to the different reaction rates of compounds containing different isotopes of these elements have been used for years to obtain information about metabolic processes in environments not accessible to direct observation. With the support of the Division of Chemistry, the Office of Multidisciplinary Activities of the Mathematical and Physical Sciences Directorate, the Directorate for Biological Sciences, and the Division of Earth Sciences, Professors Ariel D. Anbar and Kenneth H. Nealson, of the Department of Earth and Environmental Sciences at the University of Rochester, are developing techniques to explore the biogenic fractionation of isotopes of metals which play key roles in metabolic processes. By analyzing the fractionation of isotopes of copper, zinc, and iron, Professors Anbar and Nealson obtain information about the presence or absence of biological activity in general and about specific metabolic processes in particular. These studies are of particular utility for the study of life in extreme environments, where extreme conditions preclude the application of other `biomarkers.` Such environments include modern settings which are physically remote or subject to extreme environmental conditions and ancient environments which can be studied only through the geological record.