Hyper-thermostable enzyme (Lactonases) for use as microbial biocontrol agents for plant diseases (Year 6)
Michael Sadowsky and Mikael Elias
Many bacterial pathogens infect crop plants, representing major economic burdens. Current methods for controlling plant diseases due to bacterial infection have had limited success, in large part due to bacterial resistance, specificity, and environmental concerns associated with antibiotics. Novel strategies are therefore greatly needed to control microbes. Here, we take advantage of the ability of bacteria to communicate using small signaling molecules (e.g. AHLs). Bacteria communicate to regulate numerous behavior, including pathogenicity. Our group has isolated and engineered enzymes that can degrade AHLs, and thereby interfere in microbial communication. By doing so, these enzymes do not kill bacteria, but prevent their pathogenicity. In previous years of funding, we were able to show that spraying these enzymes on plant results in broad protection, extending from grasses to Dicots. In a next step, we established that this technology can translate to growth chamber experiments, and showed it effectively protects corn and other plants from infection. In exciting preliminary data, we obtained surface leaf microbiome results showing that the enzyme treatment acts by changing the microbial population structure at the plant leaf. We found that lactonase spray on infected corn leaves dramatically reduced Goss’s Wilt in Rosemount UMN fields, MN.
Therefore, we propose to perform the logical next step: evaluate this treatment in a midscale field study. This will include i) improvement of the enzyme solution for an optimal, highly active formulation; ii) examine the mechanism of protection to confirm the broad spectrum activity of the molecule and iii) determine the ability of enzyme treatment to reduce damage to crops plants in a midscale field study, including corn yield. The proposed work is expected to provide robust, replicated field work data that will validate the potential for translation of this technology to protect crop fields.
