The biochemistry of glucosinolate hydrolysis: How insects deactivate mustard oil bombs in plants?

Plants produce a large variety of chemical compounds that are believed to protect them from herbivore or pathogen attack. However, it has been difficult to prove these defensive roles, especially since certain herbivores feed without any apparent negative effects on plants with high levels of defensive molecules. One of the most interesting groups of plant defense compounds are the glucosinolates, representing sulfur-containing metabolites that are precursors of the mustard oils. Modern molecular and biochemical methods now provide researchers with new tools to test the function of plant chemical defenses in a rigorous manner, as well as to explain how defenses may be circumvented. Here we describe how herbivorous insect species biochemically manage to disarm the plants' mustard oil bombs.