Hydrogen exchange measurements have been able, in some cases, to distinguish different kinds of protein motions and to provide site-resolved information on their identity, their extent, their equilibrium and kinetic parameters, their response to ambient conditions and mutations, and their relationship to functional properties. As part of the effort to understand the significance of the dynamic dimension of protein structure and its role in protein function, these hydrogen exchange capabilities need to be improved and extended to more proteins. Studies are proposed of staphylococcal nuclease, dihydrofolate reductase, and cytochrome c initially, and other proteins more broadly. To better understand the relationships that connect hydrogen exchange behavior to protein structure and dynamics, a large quantity of results will be used to test and refine theoretical models that attempt to relate protein properties and hydrogen exchange. To extend the scope of native state hydrogen exchange methods, the mode of action of osmolytes, and their use as reverse denaturants, will be pursued. Also, larger proteins, which promise to change the balance between local fluctuations and larger unfolding reactions measured by hydrogen exchange, will be studied. To study the functional role of the dynamic dimension of protein structure, hydrogen exchange approaches will be applied to the study of enzymatic function.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM075105-02
Application #
7115871
Study Section
Macromolecular Structure and Function B Study Section (MSFB)
Program Officer
Wehrle, Janna P
Project Start
2005-09-01
Project End
2009-08-31
Budget Start
2006-09-01
Budget End
2007-08-31
Support Year
2
Fiscal Year
2006
Total Cost
$239,587
Indirect Cost
Name
University of Pennsylvania
Department
Biochemistry
Type
Schools of Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Lim, Woon Ki; Rosgen, Jorg; Englander, S Walter (2009) Urea, but not guanidinium, destabilizes proteins by forming hydrogen bonds to the peptide group. Proc Natl Acad Sci U S A 106:2595-600
Bedard, Sabrina; Mayne, Leland C; Peterson, Ronald W et al. (2008) The foldon substructure of staphylococcal nuclease. J Mol Biol 376:1142-54
Bedard, Sabrina; Krishna, Mallela M G; Mayne, Leland et al. (2008) Protein folding: independent unrelated pathways or predetermined pathway with optional errors. Proc Natl Acad Sci U S A 105:7182-7
Krishna, Mallela M G; Maity, Haripada; Rumbley, Jon N et al. (2007) Branching in the sequential folding pathway of cytochrome c. Protein Sci 16:1946-56
Englander, S Walter; Mayne, Leland; Krishna, Mallela M G (2007) Protein folding and misfolding: mechanism and principles. Q Rev Biophys 40:287-326