Primary Investigator: Jonathan Schilling
Co-Investigators: Aiym Bakytbaikyzy (Postdoctoral Research Scholar)
Industry Partners: MycoWorks
Award Type: Seed Grant - Graduate Research Scholar
Problem: Filamentous ‘white rot’ type fungi produce enzymes known as Type II Peroxidases (PODs) that not only break down plant lignin, but also break down a vast range of pollutants. For this reason, a common bioremediation co-metabolism strategy involves spreading wood mulch on top of contaminated soils to attract or inoculate with white rot fungi to stimulate POD secretion and to inadvertently (but beneficially) degrade pollutants. This strategy works, it is cheap, and it has been widely adopted; however, when remediation timeframes are limited for diffusible pollutants or when concentrations of pollutants exceed POD titers achievable by typical inoculated fungi, this approach falls short. This is unfortunate, given that the alternatives are far more expensive, and it often leaves remediation alternatives out of reach, all together.
Solution: Two possible solutions are 1) to make the more effective alternatives cheaper, or 2) to make the cheap solution more effective (our approach). Our specific approach is to target fungal strains and growth conditions that force more hyphal septation and branching/binding in order to boost POD secretion per unit of fungal biomass. This is straightforward and it is logical, but it has been not been addressed, in part because of the limitations of the fungus, Pleurotus ostreatus (Oyster mushroom) most commonly used in these applications.
Impact: Improving efficiency of mycoremediation via peroxidase enzyme increases and hyphal densification could have tremendous potential impact on industrial clean-up of pollutants. These enzymes are selective in the reactions that they catalyze, but the cascading secondary reactions are non-selective, often targeting ring-structure compounds that resemble the intended target, lignin. These ring-structure compounds include many pollutants that are otherwise challenging to clean up, including hydrocarbons, PCBs, and dioxins, making these lignin-degrading white rot fungi have potentially great value for dispersed, low-cost bioremediation.