Identifying protein targets of bioactive compounds is an effective approach to discover unknown protein functions,identify molecular mechanisms of drug action,and obtain information for optimization of lead compounds.At the same time,metabolic activation of a drug can lead to cytotoxicities.Therefore,it is very important to systemically characterize the drug and its reactive intermediate.Mass spectrometry-based proteomic approach has emerged as the most efficient to study protein functions and modifications.This review will discuss method development for the drug target discovery and the application in different fields including the drug toxicity mechanism caused by reactive metabolites.
