Schwartz Lab
NAU students in the Department of Biological Sciences take their learning to the next level
The Schwartz lab studies the relationships between soil microorganisms and environmental processes. Projects use a variety of techniques including molecular biology, culturing approaches, and stable isotope methods, and focus on microbial ecology, bioremediation, ecosystem ecology, and biofuels.
Projects
Characterization of growing microorganisms in soil through stable isotope probing with H218O Accordion Closed
Ultracentrifugation of DNA extracted from mixed-conifer soil incubated with H218O (tubes A) or H216O (tube B) for 10 days.We developed a new approach to characterize growing microorganisms in environmental samples based on labeling microbial DNA with H218O. DNA of different densities can be separated by ultracentrifugation in CsCl, allowing us to identify newly grown cells that have incorporated the heavy isotope into their DNA. In addition, cells that survived but did not divide during an incubation period can also be characterized with this new technique because their DNA will remain without label.
Ecological investigation of active soil microbial communities in McMurdo Dry Valleys Accordion Closed
We are using stable isotope probing with H218O to identify active soil microorganisms in the McMurdo Dry Valleys of Antarctica.
Experimental plot in Taylor Valley, Antarctica.Impact of monsoon rains on soil microorganisms Accordion Closed
Arizona and New Mexico receive half of their annual precipitation during the summer monsoon season, making this large-scale rain event critical for ecosystem productivity and dynamics. We are using the monsoon rains to explore the response of soil microbial community structure to natural moisture pulses in a semiarid grassland.
Images of the grassland before, during, and after monsoon rains (from left to right).Influence of soil colloidal fraction on the mineralization rate of extracellular DNA Accordion Closed
We are measuring how adsorption of extracellular DNA onto clay and organic matter affects DNA mineralization in soil.
DNA degradation curve