MCA: Geosymbiotic interactions as innovation in Earth and environmental systems: Feedbacks between biological activity, chemical gradients and mineral phases at the pore scale

University Of California-Davis, Davis CA

Investigators

Abstract

Microbe-mineral interactions govern contaminant, carbon and nutrient transformation, and thus are critical to ecosystem function. Moreover, these biogeochemical interactions and their products can be harnessed to provide science-based solutions to many environmental and technological challenges. The goal of this project is to provide explicit spatially and temporally resolved rates and mechanisms of biogeochemical reactions in metal-microbe-mineral systems by developing new analytical and imaging tools. This project will provide research experiences to community college transfer students and underrepresented undergraduate students intending to pursue graduate degrees. The PI will leverage the creative advances facilitated by her MCA research to develop new educational products, including materials for a new laboratory-based course, “Microfluidics Labs”. Finally, this project will enhance research infrastructure through the addition of optical fluorescence and infrared microscopes to the X-ray microprobe beamline at the Stanford Synchrotron Radiation Lightsource as well as the development of new image analysis workflows. This project will develop analytical and imaging capabilities that shift the paradigm for studying biogeochemical transformations in confined spaces. The goal is to quantify the chemical and biological feedbacks that shape metal-microbe-mineral interactions. Using manganese biomineralization as a case study, the PI will provide spatially- and temporally-explicit measurements of biological activity (bioreporter gene fusions) and aqueous environmental conditions (optode sensor films) coupled to biofilm chemistry (FTIR) and metal speciation and mineral precipitation (X-ray fluorescence). This approach will provide unparalleled insight into chemical transformations that occur within a cell’s immediate environment. Determination of reaction rates and mechanisms through measurements of average properties often fail to reproduce macroscopic behavior or provide correct mechanisms; the focus on the chemistry occurring at the cellular level enable the researchers to develop accurate mechanistic rates. Additionally, the visualization of phenotypic heterogeneity within microbial communities and chemical transformations will deepen the understanding of geosymbiotic interactions in environmental systems. This project is jointly funded by the Geobiology and Low Temperature Geochemistry Program and the Division of Earth Sciences to support projects that increase research capabilities, capacity and infrastructure at a wide variety of institution types, as outlined in the GEO EMBRACE DCL. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.