CD STUDY OF UREA INDUCED UNFOLDING OF GAL REPRESSOR OF E COLI

大肠杆菌的gal抑制因子（GalR）调节来自

The gal repressor of E. Coli (GalR) regulates transcription from the gal operon. It is a dimeric protein that binds one molecule of inducer, D-galactose, per subunit. The protein is obtained from a bacterial expression system and is often found in inclusion bodies. While investigating renaturation of GalR from inclusion bodies, we became interested in its unfolding properties. Intrinsic tryptophan fluorescence is substantially quenched and its emission peak is red shifted when the protein unfolds in urea. Binding of D-galactose causes significant stabilization against urea induced denaturation. CD measurements will provide an independent measure of GalR unfolding in urea which can be correlated with our fluorescence data.