Linamarase
Linamarase, or beta-D-glucosidase (EC3.2.1.21), is an enzyme found in many plants including cassava and the butter bean.
In cassava it is found in the cell walls. When the plant is chewed or ground, it exposes the enzyme to compounds like linamarin and lotaustralin which release cyanide compounds that can be lethal to the eater. In humans, chronic toxicity is more likely than death.