Arizona State University Dept. of Chemistry & Biochemistry Effect of Autotrophic Metabolism on Dissolved Organic Carbon in Yellowstone National Park Kathryn Mayer Arizona State University Dept. of Chemistry & Biochemistry

Why Carbon in Hot Springs? Biodiversity Geochemical variability Extreme environment Microbial metabolism Organic Carbon trends difficult to characterize

Metabolism effects the organic carbon of a system “CH2O” + O2 CO2 + H2O Autotrophy – primary producers, makes organic C Photosynthetic Chemosynthetic Heterotrophy –uses C from autotrophs

Project Heterotroph ‘06 Goal: Assess metabolism in 3 different hot spring/outflow systems by measuring amount of dissolved organic carbon (DOC) Hot Spring Chemosynthetic Zone Photosynthetic Zone ~73ºC HS: Filtered Hot Spring Water + Zone Water DI: Deionized Water + Zone Water UC: Filtered Hot Spring Water

Hot Spring Chemosynthetic Zone Photosynthetic Zone ~73ºC

Conceptual Model Photosynthesis Chemosynthesis UC Control Heterotrophy DI Control

Methods Use TOC-V Analyzer to measure amount of DOC NDIR Detector “CH2O” CO2 680ºC

Results… Not what we expected!

We should have called this Project Autotroph NOT Heterotroph Increases in DOC concentrations Autotrophy C production in Dark and Light bottles Photosynthesis & Chemosynthesis Genomic studies tell us there are autotrophs & heterotrophs present. This experiment does not show heterotrophy.

Future Work Study organic compound compositional changes with Electrospray Ionization Mass Spectrometry (ESI-MS) Experiment being planned for Summer ‘08 Thank you… Dr. Hilairy Hartnett & Katie Alexander Women & Philanthropy