Chemistry and Biochemistry
University of the Sciences
United States of America
Relationships between protein structure and function have long been studied with a variety of techniques. Scanning calorimetry (DSC) and its newer cousin, isothermal titration calorimetry (ITC), are capable of yielding a wealth of thermodynamic information about the structures of these macromolecules. These techniques, along with fluorescence and UV-VIS spectroscopy, are used in this lab to study structural properties of exchangeable serum apolipoproteins (apo-A, apo-E) associated with high-density lipoprotein (HDL). Since HDL is known to be involved in reverse cholesterol transport, i.e., transport of cholesterol from peripheral tissue to liver, such studies are of interest in the elucidation of molecular events associated with heart disease. DSC, for example, is being used to study the thermal unfolding of various isoforms of apo-E in order to learn about the structures and stabilities of secondary structural motifs that occur in the tertiary structures of the proteins and also to study the structural changes that are brought about by the few amino acid substitutions that constitute the differences in sequence between these isoforms. ITC and fluorescence, whenever possible, are used to learn about the interactions between exchangeable apolipoproteins with phospholipid. Smaller model compounds, such as amphipathic helical peptides, are also used in such studies in an attempt to learn about such important thermodynamic properties as binding constants, or partition coefficients, free energies, enthalpies and entropies, and also heat capacities of interaction.
Using scanning calorimetry (DSC), isothermal titration calorimetry (ITC), fluorescence and UV-VIS spectroscopy to study the relationships between protein structure and function.
Gazzara JA, Phillips MC, Lund-Katz S, Palgunachari MN, Segrest JP, Anantharamaiah GM, Rodrigueza WV, Snow JW. Effect of vesicle size on their interaction with class A amphipathic helical peptides. Journal of lipid research. 1997 Oct 1;38(10):2147-54.
Veloski CA, McCann RA, Snow JW. An analytical model for the phase behavior of cholesteryl esters in intracellular inclusions. Biochimica et Biophysica Acta (BBA)-Lipids and Lipid Metabolism. 1994 Jul 14;1213(2):183-92.
Snow JW, Glick JM, Phillips MC. The phase behavior of cholesteryl esters in intracellular inclusions. Journal of Biological Chemistry. 1992 Sep 15;267(26):18564-72.