Denature /(?)/

De·na·ture

Denature

v. t.
  1. To deprive of its natural qualities; change the nature of.
  2. to render (ethyl alcohol) unfit to drink by adding in toxic or unpalatable substances (such as benzene or pyridine) which nevertherless permit alcohol to be used as a solvent.
  3. modify the tertiary structure of (a protein or nucleic acid) so as to reduce or destroy its characteristic biological activity.

Denature

v. i.
  1. To become denatured.