Lectins are a large family of proteins that occur throughout nature. Not all lectins are good; ricin is a deadly lectin isolated from castor oil plants and can be fatal. Less than 2 mg is sufficient to likely kill an adult with death occurring within 36-72 hours.
Ricin has two domains; the first allows the protein to enter a cell and the second has N-glycosidase enzymatic activity. Most lectins do not have enzymatic activity but ricin is one of those that does.
The N-glycosidase enzymatic activity produces which of the following deadly results?