Fully reduced ribonuclease A does not expand at high denaturant concentration or temperature
Jaby Jacob1, Robin S Dothager, P Thiyagarajan
1Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA. jjacob@amgen.com
Journal of Molecular Biology
|February 13, 2007
Abstract:
The dimensions of a denatured protein, fully reduced ribonuclease A (r-RNase A), have been measured using synchrotron-based small angle X-ray scattering. The radius of gyration, 34-35 A, is unchanged from 0-6 M guanidinium chloride and from 20-90 degrees C at pH 2.5, and agrees with the known scaling behavior for a multitude of chemically denatured states. The polypeptide is behaving as a statistical coil in the non-interacting, high-temperature limit.
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