USE OF „REPORTER GROUPS” IN STRUCTURE-FUNCTION STUDIES OF PROTEINS

Abstract
A new technique has been developed for the correlation of function with structure in protein molecules. A group which is sensitive to changes in environment and which can transmit a signal to an appropriate detector is introduced into a specific position in the protein. This group may report changes in its environment caused either by direct interaction with substrate or by a conformational alteration in the protein structure. An application of this method is described in which the compound 2-bromoacetamido-4-nitrophenol is reacted with the methionine residue near the active serine of chymotrypsin. On mixing substrates and inhibitors with the modified protein, character -istic difference spectra are obtained. Some of the applications and limitations of the method are discussed.