Unfolding of the regulatory subunit of cAMP-dependent protein kinase

Biochemistry 1991, 30, 3035-3040

3035

Unfolding of the Regulatory Subunit of CAMP-Dependent Protein Kinase It Darryl A. Lebn, Wolfgang R. G. Dostmann, and Susan S . Taylor* Department of Biochemistry, University of California, San Diego, 9500 Gilman Drive. La Jolla, California 92093-0654 Received October 3, 1990; Revised Manuscript Received January 2, 1991

I was followed by monitoring the intrinsic protein fluorescence. Unfolding proceeds in at least two stages. First, the quenching of fluorescence due to c A M P binding is abolished a t relatively low levels of urea (