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Protein folding research often finds complex kinetic behavior which shows that unfolded molecules take several stages to convert to the fully native form. A Pro- variate of SNase's unfolding and folding kinetic mechanism was characterized using stopped-flow fluorescence methods, with alanines and glycines used in place of six proline residues. The folding kinetics still demonstrate a complex denaturant dependence, even though complicating factors such as prolines have been removed. A sequential four-state folding mechanism can be used to model the primary stages in unfolding and folding.

Individual protein domains and two domains in combination were prepared by enzymatic and chemical cleavage of turkey ovomucoid followed by isolation and purification by size-exclusion and ion-exchange chromatography. Silica bonded-phase HPLC columns were made from either whole or isolated domains of turkey ovomucoid. The protein columns were tested for chiral recognition by their abilities to resolve enantiomers among a wide range of racemates. The columns made from whole turkey ovomucoid displayed chiral activity toward many racemates, where as a combination of the first and second domain resolved only a selected number of aromatic weak bases. The first and second domains independently gave no appreciable chiral activity. The turkey ovomucoid third domain exhibited enantioselective protein binding for fused-ring aromatic weak acids. Glycosylation of the third domain did not affect chiral recognition. Titration of the third domain with model compounds in conjunction with NMR measurements enabled the identification of the amino acids responsible for binding. Molecular modeling of the ligand-protein complexation provided insights into the ability of a protein surface to discriminate enantiomers on the basis of multiple intermolecular interactions.

The backbone 1H and 15N resonances of unligated staphylococcal nuclease H124L were assigned by three-dimensional (3D) 1H-15N nuclear Overhauser- multiple-quantum coherence (NOESY-HMQC) nuclear magnetic resonance spectroscopy. Secondary structural elements (alpha-helices, beta-sheets, reverse turns and loops) were determined by analysis of patterns of NOE connectivities present in the 3D spectrum.

The biological activity of the selected peptides from the combinatorial library in bacteria, fungi and mammalian cells is studied to characterize the selected peptides and to compare the activity of antimicrobial peptides (AMPs) in vitro and in vivo. The analysis has shown that the methods focusing on screening peptide libraries in vitro for membranes with the appropriate interfacial activity has enabled the design, selection and discovery of novel, potent and broad-spectrum membrane-active antibiotics.