Quantitative measurement of learning in Caenorhabditis elegans in response to an engineered nematicidal bacterium

Quantitative measurement of learning in Caenorhabditis elegans in response to an engineered nematicidal bacterium

Despite their global prevalence, there are very few strategies to prevent infections due to parasitic nematodes. Recent studies have shown that bacteria engineered using the principles of synthetic biology may serve as an alternative approach to intoxicating nematodes. While these engineered bacteria were initially shown to be relatively efficacious in intoxicating the model nematode Caenorhabditis elegans, the nematodes quickly learned to avoid the engineered bacteria through aversive associative learning. In this study, we sought to use nematode learning assays to quantify the ideal amounts of toxin and attractant required to reduce aversive learning of C. elegans towards the engineered nematicidal bacteria. Testing the intoxication efficiency of the engineered bacteria under different amounts of toxin and attractant allows us to measure aversive learning through learning specificity. Our results are among the first comprehensive studies of learning in C. elegans in response to a nematicidal protein, and may allow for optimization of treatment regiments when using nematicidal bacteria as a biocontrol or therapeutic agent.