CAREER: Quantifying the flux and isotope effects associated with sulfur-bearing intermediate species within dissimilatory sulfate reduction

Harvard University, Cambridge MA

Investigators

Abstract

The story of Earth's history is locked within marine sediments, with the stable isotopes of sulfur providing much of this information and timeline. Despite this utility, what controls the behavior of these isotopes is incompletely understood. The goal of this CAREER award is to systematically evaluate how sulfur isotopes are fractionated when growing on different soluble sulfur compounds. In the same fashion that humans breathe oxygen, these organisms can grow on sulfate, sulfite, thiosulfate and trithionate; these are the targeted substrates. This work will thus develop a framework whereby specific fractionations will be linked to particular metabolic processes. In essence, this is a 'fingerprinting' process. At the core of this research is the team-based STEM model where local high school students will work closely with undergraduates from a suite of colleges in New England to conduct all the experimental work outlined above. This will bring young scientists along on the path of designing research questions, performing lab-based experiments, processing data and working with particular instruments, and finally relating these results to the published literature.