Edward K. Koepf

Learn More
The structure of gelsolin has been determined by crystallography and comprises six structurally related domains that, in a Ca2+-free environment, pack together to form a compact globular structure in which the putative actin-binding sequences are not sufficiently exposed to enable binding to occur. We propose that binding Ca2+ can release the connections(More)
Twelve analogues of diclofenac (1), a nonsteroidal antiinflammatory drug and known inhibitor of transthyretin (TTR) amyloid formation, were prepared and evaluated as TTR amyloid formation inhibitors. High activity was exhibited by five of the compounds. Structure-activity relationships reveal that a carboxylic acid is required for activity, but changes in(More)
The objective of this study was to evaluate the suitability of the WW domain as a desirable model system to understand the folding and stability of an isolated three-stranded antiparallel beta-sheet structure. The WW domain was subjected to thermal and chaotropic denaturation/reconstitution utilizing a variety of biophysical methods. This three-stranded(More)
We had previously identified the WW domain as a novel globular domain that is composed of 38-40 semiconserved amino acids and is involved in mediating protein-protein interaction. The WW domain is shared by proteins of diverse functions including structural, regulatory, and signaling proteins in yeast, nematode, and mammals. Functionally it is similar to(More)
The WW domain adopts a compact, three-stranded, antiparallel beta-sheet structure that mediates protein-protein interactions by binding to xPPxY-based protein ligands, such as the PY-ligand (EYPPYPPPPYPSG) derived from p53 binding protein-2. The conserved Trp residues, after which this domain was named, were replaced with Phe so their importance in(More)
The folding kinetics of a three-stranded antiparallel beta-sheet (WW domain) have been measured by temperature jump relaxation. Folding and activation free energies were determined as a function of temperature for both the wild-type and the mutant domain, W39F, which modifies the beta(2)-beta(3) hydrophobic interface. The folding rate decreases at higher(More)
BACKGROUND Normally, gelsolin functions in plasma as part of the actin-scavenging system to assemble and disassemble actin filaments. The Asp 187-->Asn (D187N) Asp 187-->Tyr (D187Y) gelsolin mutations facilitate two proteolytic cuts in the parent protein generating a 71-residue fragment that forms amyloid fibrils in humans, putatively causing Finnish type(More)
Horse plasma gelsolin labelled with benzophenone-4-isothiocyanate can be photochemically cross-linked to rabbit cardiac tropomyosin. The cross-linking proceeds with greater efficiency in calcium-containing buffers. Further evidence for interaction between these proteins is provided by retention of fluorescently labelled gelsolin on tropomyosin-agarose(More)
Perturbing the structure of the Pin1 WW domain, a 34-residue protein comprised of three beta-strands and two intervening loops has provided significant insight into the structural and energetic basis of beta-sheet folding. We will review our current perspective on how structure acquisition is influenced by the sequence, which determines local conformational(More)
Under nondenaturing conditions, 1 mol of horse plasma gelsolin reacts with 1.9 +/- 0.5 mol (mean +/- SD, n = 6) of the sulfhydryl-specific fluorescent reagent 6-acryloyl-2-dimethylaminonaphthalene (acrylodan). The degree of labeling in 6 M guanidine-HCl increases to about 3 mol of acrylodan per mole of gelsolin. Viscosity studies show that the modified(More)