Microbial communities are all around us - in soil, your body, and every local pond - breaking down and recycling nutrients. The interdependence of these communities has been known for over a century, but the bulk of laboratory microbiology is done on one species in isolation. Determining how nutrients flow between these different species is essential to better predict how microbial communities can process heavy metal pollution, effect bioremediation, or adapt to new ecological settings. This project will develop the sensing tools to adequately measure interrelated metabolism in a spatially and temporally defined manner and develop smaller (capillary-based) model systems able to better mimic the real-world settings seen in the environment while remaining suitable for use in the lab. Educational outreach includes partnering with the local Head Start preschool to expose disadvantaged preschoolers (including minorities, disabled, and the homeless) and their siblings to STEM and sensing, and working with the county high school system to place research interns into the lab for this project to prepare them for a future career in scientific research and engineering.
The goal of this CAREER award is to develop and apply optical nanosensors to monitor metabolic markers throughout striated environmental microbial communities in capillary culture systems. This will address the question of how well these capillary approaches are able to recapitulate the striated consortia seen in larger scale systems. The central hypothesis is that capillary based communities will establish similar gradients in nutrients (oxygen, iron, sulfate, lactate) to larger column-based systems and show faster establishment. Three specific aims build toward this goal: 1: Optimize persistent luminescence "glow" nanosensors for quantification of sulfate and iron. 2: Optimize nanosensors for quantification of lactate in aerobic and anaerobic environments. 3: Determine how well capillary based microbial systems mimic the nutrient gradients of larger column-based approaches. The expected outcomes of this CAREER award include a new nanosensor technology, an expansion of the range of analytes measurable (iron, sulfate, lactate), and the development of a relationship between small and large model systems for studying microbial consortia. These outcomes will advance the field of sensors through the use of persistent luminescence for background reduction in nanosensors and new sensors for spatiotemporal monitoring of these key analytes. This project will quantify how well capillary based microbial culture approaches recapitulate the complicated environment established in larger columnbased systems. This advance is made possible with these new tools to monitor inter-species metabolism. The capillary based microbial communities and corresponding nanosensors can monitor transport dynamics in a range of fields including heavy metal pollution, bioremediation, and microbial ecology (especially in attempts to understand microheterogeneity). The tools and techniques developed in this research can benefit scientific communities researching any three-dimensional biological system. Related applications where this work can make a large impact include medical models (e.g. tumor organoids, organ-on-a-chip systems, biofilms, and 3D tissue scaffolds), other environmental systems (e.g. microbial mats), and industrial systems (e.g. biotherapeutic production, wastewater treatment). The ability to spatiotemporally monitor metabolism with nanosensors will enable a wide range of advances in all of these complex metabolically linked systems. This work will also be integrated to a first year Studio Biology course which is taught in an immersive laboratory setting rather than in a classroom. In this module, students will explore microbial community metabolism, and apply nanosensors in scientific investigation.
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.
