Isotope studies of microbial sulfate reduction

University Of Maryland, College Park, College Park MD

Investigators

Abstract

This proposal requests funds to support an experimental study of S isotope fractionation by sulfate reducing organisms, coupling well-established methods for measuring the fractionation of four stable isotopes of sulfur with experiments involving 17O isotope-labeling techniques. The project aims to explore the response of these organisms to temperature and electron donors. The work will involve sulfur isotope analysis of samples from culture experiments undertaken prior to submission of the proposal as part of the first part of a significantly larger project to study the sulfate reduction metabolism. It is anticipated that the support will lead to the publication of a paper on the metabolic response of Desulfobacterium autotrophicum to changes in the electron donor at two temperature conditions. Understanding the sedimentary sulfur cyle and the catalyses by mircobes is fundamental for understanding the global carbon cycle. The proposal will provide partial support for this work in the form of several months of support for a graduate student and partial support for analytical costs.