denature

• ⇰ To deprive of its natural qualities; change the nature of.
• ⇰ 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.
• ⇰ modify the tertiary structure of (a protein or nucleic acid) so as to reduce or destroy its characteristic biological activity.

• ⇰ To become denatured.