Practice question

DEPC (diethylpyrocarbonate) is an alkylating agent used to inactivate RNases during RNA isolation. RNases are highly stable and ubiquitous enzymes that degrade RNA rapidly. DEPC covalently modifies histidine, lysine, and other nucleophilic residues at the active site of RNases, irreversibly inhibiting them. Water and glassware are treated with 0.1% DEPC and autoclaved to hydrolyze excess DEPC to ethanol and CO2. DEPC does not digest RNA, chelate metals, or digest proteins; its critical role is RNase inactivation to preserve RNA integrity throughout extraction.