Biochemists and structural biologists have learned a tremendous amount about a common group of calcium-binding proteins containing the """"""""EF-han motif"""""""" (troponin C, parvalbumin, calmodulin, etc.) from which there is a relative wealth on information on their structures and function. However another unique group of proteins exist, the calcium-binding a-lactalbumins and lysozymes, which are """"""""non-classical"""""""" calcium-binding proteins which have a unique and distinct coordination geometry. The overall topography and role of the cation binding loop in the calcium-binding alpha-lactalbumins has yet to b fully understood. Furthermore, the alpha-lactalbumins are unique in their high propensity to form the intermediate """"""""molten globule"""""""" folding state. They also bind the metal ion zinc at another distinct site, which modulates the conformational properties of the calcium bound form.
The aims of this project are to unravel the structural and functional properties of the calcium binding properties of this milk protein, which modifies the specificity of the enzyme galactosyl transferase in lactose biosynthesis.
The specific aims of this project are to: 1. Unravel the determinants involved in calcium binding (and in the folding an structural integrity of the protein). 2. Determine which residues of the protein are buried in membranes. 3. Determine the role of the amino acids involved in zinc binding.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM056970-02
Application #
6019403
Study Section
Physical Biochemistry Study Section (PB)
Project Start
1998-08-01
Project End
2002-07-31
Budget Start
1999-08-01
Budget End
2000-07-31
Support Year
2
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Ohio State University
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
098987217
City
Columbus
State
OH
Country
United States
Zip Code
43210
Permyakov, Serge E; Pershikova, Irina V; Zhadan, Andrei P et al. (2005) Conversion of human alpha-lactalbumin to an apo-like state in the complexes with basic poly-amino acids: toward understanding of the molecular mechanism of antitumor action of HAMLET. J Proteome Res 4:564-9
Permyakov, Serge E; Makhatadze, George I; Owenius, Rikard et al. (2005) How to improve nature: study of the electrostatic properties of the surface of alpha-lactalbumin. Protein Eng Des Sel 18:425-33
Chaudhuri, Dipankar; Narayan, Mahesh; Berliner, Lawrence J (2004) Conformation-dependent interaction of alpha-lactalbumin with model and biological membranes: a spin-label ESR study. Protein J 23:95-101
Permyakov, S E; Uversky, V N; Veprintsev, D B et al. (2001) Mutating aspartate in the calcium-binding site of alpha-lactalbumin: effects on the protein stability and cation binding. Protein Eng 14:785-9
Peterson, F C; Anderson, P J; Berliner, L J et al. (1999) Expression, folding, and characterization of small proteins with increasing disulfide complexity by a pT7-7-derived phagemid. Protein Expr Purif 15:16-23