Designing biosensors to inform ecosystem engineering

September 10, 2025

Location

Online

Presenters

Ilenne Del Valle

Research Staff Scientist, Oak Ridge National Laboratory, USA

Outline

An effective strategy to enhance the resilience and productivity of biofeedstocks is to engineer plant-associated microbiomes. One example of microbiome manipulation is the use of biofertilizers and biopesticides containing plant growth-promoting microbes to improve plant health and pest resistance. However, these introduced microbes often fail to establish, persist, and consistently deliver benefits under varying environmental conditions.

To address these challenges, we are developing novel biosensors to provide real-time measurements of microbial persistence and metabolic activity in complex environments. Here, we describe the development of Bacillus velezensis as a biosensor to support microbiome engineering in the plant rhizosphere. Specifically, we are engineering a gas-based biosensor that produces an indicator gas detectable by gas chromatography–mass spectrometry, enabling real-time, non-disruptive monitoring of microbial activity in soils from laboratory to greenhouse scales. We are utilizing a constitutive version of this gas biosensor to investigate how genetic traits influence B. velezensis survival under abiotic and biotic stress conditions, as well as inducible versions to assess the bioavailability of root exudates and their roles in plant-microbe interactions.

Overall, these technical advancements will enable critical in situ monitoring of microbial activity, facilitating the identification of genetic modifications that can predictably and safely improve the performance of engineered plant biostimulants.