ADP and ATP Destabilize the Escherichia coli Chaperonin GroEL whereas Potassium Ion Does Not; Structural Evidence by the Solution Small Angle X-ray Scattering Measurements (MOLECULAR BIOLOGY AND INFORMATION-Biopolymer Structure)

Abstract

ATP, ADP and Mg2+ dependence of the denaturation by Guanidine Hydrochloride of the GroEL, a chaperonin originated from Escherichia coli, was investigated by the solution small-angle X-ray scattering (SAXS) measurements using synchrotron radiation source. Disappearance of the quaternary structure of the GroEL was observed by the Kratky plots of the scattered intensities. Disintegration of the quarternary structures occurred at Guanidine Hydrochloride (GdnHCl) concentration of 0.8M in the presence of Mg-ATP, 1.1M for Mg-ADP and 1.3M for K+; decreasing curves of weight averaged molecular weights observed from forward scatterings are shown to be compatible with this results. The destabilization of GroEL by nucleotides was proved structurally.