Confirmation of the hierarchical folding of RNase H: a protein engineering study.
The kinetic intermediate of RNase H is structured in a core region of the protein. To probe the role of this intermediate in the folding of RNase H, the folding kinetics of mutant proteins with altered native state stabilities were investigated. Mutations within the folding core destabilize the kinetic intermediate and slow refolding in a manner consistent with an obligatory intermediate model. Mutations outside of the folding core, however, do not affect the stability of the kinetic intermediate but do perturb the native state and transition state. These results indicate that interactions formed in the intermediate persist in the transition and native states and that RNase H folds through a hierarchical mechanism.
Raschke
T M
TM
Department of Molecular and Cell Biology, University of California, Berkeley, 229 Stanley Hall, Berkeley, California 94720, USA.
Kho
J
J
Marqusee
S
S
D019943:Amino Acid Substitution; D002942:Circular Dichroism; D004795:Enzyme Stability; D007700:Kinetics; D008958:Models, Molecular; D009154:Mutation; D011489:Protein Denaturation; D015202:Protein Engineering; D017510:Protein Folding; D017433:Protein Structure, Secondary; D016914:Ribonuclease H / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D013816:Thermodynamics; D014508:Urea
D014508:Urea; D016914:Ribonuclease H