Скачать или смотреть InterRidge 2021 12 webinar by Dr. Min Sub Sim

InterRidge 2021 Webinar Series - Earth Science, Life Science and Our Future #4

-Title: Sulfur isotopes as qualitative and potentially quantitative tracers of past microbial activity
-Lecturer: Min Sub Sim (Associate Professor, Seoul National University)
-Day: 23rd December, 2021

Sulfur isotope fractionation between sulfate and sulfide has been used as a diagnostic marker for microbial sulfate reduction, which can be recognized in modern aquatic environments and are also preserved in sedimentary rocks over geological time. A wide range of fractionation has attracted particular attention since it may serve as a quantitative indicator of environmental or physiological variables such as specific respiration rates. Microbial sulfur isotope fractionation has been often explored as a single net effect. In theory, however, the magnitude of isotope fractionation depends upon the sulfur isotope effect imparted by the involved enzymes and the relative rate of each enzymatic reaction. The former defines the possible range of fractionation, while the latter responds to environmental stimuli, providing an underlying rationale for the varying fractionations. Recently, the direct assessment of individual intracellular processes emerges as a promising means for the quantitative analysis of isotope fractionation. Sulfur isotopic studies on intracellular metabolites have begun since the development of MC-ICP-MS method for sulfur isotope analysis, and it was in the last decade that the kinetic isotope effects of the enzymes involved were experimentally determined. The analysis of all three isotopic ratios of sulfur have also added a new dimension in modelling the sulfur metabolic network. These recent advances and ongoing efforts will provide a firm empirical basis for a quantitative interpretation of sulfur isotope fractionation.

If there is copyrighted content on this webinar, please contact InterRidge ([email protected])

[email protected]
www.interridge.org