Gafni/Steel Selected Publications

2011

Johnson, R.D., Schauerte, J.A., Wisser, K.C., Gafni, A., Steel, D.G.
Direct Observation of Single Amyloid-beta (1-40) Oligomers on Live Cells: Binding and Growth at Physiological Concentrations.
PLoS One. 2011; 6(8): e23970. (Link)

Brender, J.R., Lee, E.L., Hartman, K., Wong, P.T., Ramamoorthy, A., Steel, D.G., Gafni, A.
Biphasic Effects of Insulin on Islet Amyloid Polypeptide Membrane Disruption.
Biophys J. 2011; 100(3): 685-92. (Link)

2010

Schauerte, J.A., Wong, P.T., Wisser, K.C., Ding, H., Steel, D.G., Gafni, A.
Simultaneous Single-Molecule Fluorescence and Conductivity Studies Reveal Distinct Classes of Abeta Species on Lipid Bilayers.
Biochemistry. 2010; 49(14):3031-9. (Link)

2009

Ding, H., Wong, P.T., Lee, E.L., Gafni, A., Steel, D.G.
Determination of the Oligomer Size of Amyloidogenic Protein Beta-Amyloid(1-40) by Single-Molecule Spectroscopy.
Biophys J. 2009;97(3):912-21. (Link)

Tapley, T.L., Korner, J.L., Barge, M.T., Hupfeld, J., Schauerte, J.A., Gafni, A., Jakob, U., Bardwell, J.C.
Structural Plasticity of an Acid-activated Chaperone Allows Promiscuous Substrate Binding.
Proc Natl Acad Sci U S A. 2009;106(14):5557-62. (Link)

Wong, P.T., Schauerte, J.A., Wisser, K.C., Ding, H., Lee, E.L., Steel, D.G., Gafni, A.
Amyloid-Beta Membrane Binding and Permeabilization are Distinct Processes Influenced Separately by Membrane Charge and Fluidity.
J Mol Biol. 2009;386(1):81-96. (Link)

2008

Shi, J., Dertouzos, J., Gafni, A., Steel, D.
Application of Single-Molecule Spectroscopy in Studying Enzyme Kinetics and Mechanism.
Methods Enzymol. 2008;450:129-57. (Link)

Brender, J.R., Lee, E.L., Cavitt, M.A., Gafni, A., Steel, D.G., Ramamoorthy, A.
Amyloid Fiber Formation and Membrane Disruption are Separate Processes Localized in Two Distinct Regions of IAPP, the Type-2-Diabetes-Related Peptide.
J Am Chem Soc. 2008;130(20):6424-9. (Link)

2006

Shi, J., Gafni, A., Steel, D.
Simulated Data Sets for Single Molecule Kinetics: Some Limitations and Complications of Data Analysis.
Eur Biophys J. 2006;35(8):633-45. (Link)

Shi, J., Dertouzos, J., Gafni, A., Steel, D., Palfey, B.A.
Single-Molecule Kinetics Reveals Signatures of Half-Sites Reactivity in Dihydroorotate Dehydrogenase a Catalysis.
Proc Natl Acad Sci U S A. 2006;103(15):5775-80. (Link)

2005

Brender, J.R., Dertouzos, J., Ballou, D.P., Massey, V., Palfey, B.A., Entsch, B., Steel, D.G., Gafni, A.
Conformational Dynamics of the Isoalloxazine in Substrate-Free P-Hydroxybenzoate Hydroxylase: Single-Molecule Studies.
J Am Chem Soc. 2005;127(51):18171-8. (Link)

Sherman, W.A., Blouse, G.E., Perron, M.J., Tran, T., Shore, J.D., Gafni, A.
Enthalpy Measurement Using Calorimetry Shows a Significant Difference in Potential Energy Between the Active and Latent Conformations of PAI-1.
Biol Chem. 2005;386(2):111-6. (Link)

Before 2005

Shi, J., Palfey, B. A., Dertouzos, J., Jensen, K. F., Gafni, A., Steel, D. (2004) Multiple States of the Tyr318 Leu Mutant of Dihydroorotate Dehydrogenase Revealed by Single-Molecule Kinetics J. Am. Chem. Soc.  126(22); 6914-6922.

Wisser, K.C., Schauerte, J.A., Burke, D.T., Galecki, A., Chen, S., Miller, R.A. and Gafni, A. (2004) Mapping Tissue-Specific Genes Correlated with Age-Dependent Changes in Protein Stability and Function.  Archives of Biochemistry and Biophysics 432,58-70.

Rhodes, E., and Gafni, A. (2003) Micelle formation by a fragment of human islet amyloid polypeptide. Biophys. J. 84(5):3480-7.

Fisher, C.J., Gafni, A., Steel, D.G., and Schauerte, J.A. (2002) The triplet-state lifetime of indole in aqueous and viscous environments:  significance to the interpretation of room temperature phosphorescence in proteins. J. Am. Chem Soc. 124(35):10359-66.

Dirnbach, E., Steel, D.G., and Gafni, A. (2001) Mg2+ binding to alkaline phosphatase correlates with slow chanes in protein lability. Biochemistry 40(37):11219-26.

Fischer, C.J., Schauerte, J.A., Wisser, K.C., Steel, D.G., and Gafni, A. (2001) Differences in the pathways for unfolding and hydrogen exchange among mutants of Escherichia coli alkaline phosphatase. Biochem. Biophys. Acta. 1545(1-2):96-103.

Fischer, C.J., Schauerte, J.A., Wisser, K.C., Gafni, A., and Steel, D.BG. (2000) Hydrogen exchange at the ore of Escherichia coli alkaline phosphatase studied by room-temperature phosphorescence.  Biochemistry 39(6):1455-61.

Dirnbach, E., Steel, D.G., and Gafni, A. (1999) Proline isomerization is unlikely to be the cause of slow annealing and reactivation during the folding of alkaline phosphatase.  J. Biol. Chem.  274(8):4532-6.

Lewis, M.K., Wolanin, P., Gafni, A., Steel, D.G. (1998) Near-Field Scanning Optical Microscopy of Single Molecules by Femtosecond Two-Photon Excitation.  Optics Letters 23;1111-1113.

Schauerte, J.A., Steel, D.G., and Gafni, A. (1997) Time-resolved room temperature tryptophan phosphorescence in proteins. Methods Enzymol. 278:49-71.

Hansen, J.E., Steel, D.G., and Gafni, A. (1996) Detection of a pH-dependent conformational change in azuring by time-resolved phosphorescence. Biophys. J. 71(4):2138-43.

Subramaniam, V., Steel, D.G., and Gafni, A. (1996) In vitro renaturation of bovine beta-lactoglobulin A leads to a biologically active but incompletely refolded state. Protein Sci. 5(10):2089-94.

Schauerte, J.A., Gafni, A., and Steel, D.G. (1996) Improved Differentiation Between Luminescence Decay Components by Use of Time-Resolved Optical Activity Measurements and Selective Lifetime Modulation. Biophys. J. 70:1996-2000.

Schauerte, J.A., and Gafni, A. (1995) Photodegradation of Tryptophan Residues and Attenuation of Molecular Chaperone Activity in Alpha-Crystallin are Correlated. Biochem. Biophys. Res. Comm. 212:900-905.

Schauerte, J.A., Schlyer, B.D., Steel. D.G., Gafni, A. (1995) Nanosecond Time-Resolved Circular Polarization of Fluorescence: Study of NADH Bound to Horse Liver Alcohol Dehydrogenase. Proc. Natl. Acad. Sci. USA92:569-573.

Schlyer, B.D., Schauerte, J.A., Steel, D.G., and Gafni, A. (1994) Time-resolved room temperature protein phosphorescence: nonexponential decay from single emitting tryptophans. Biophys. J. 67:1192-1202.

Hansen, J. and Gafni, A. (1994) Fluorescence Detection of Conformational Changes in GroEL Induced by Thermal Switching and Nucleotide Binding.  J. Biol. Chem 269:6286-6289.

Mersol, J.V.,Steel, D.G., Gafni, A. (1993) Detection of Intermediate Protein Conformations by Room Temperature Phosphorescence Spectroscopy During Denaturation of Escherichia Coli Alkaline Phosphatase. Biophysical Chemistry 48:281-291.

Mersol, J.V.,Steel, D.G., Gafni, A. (1991) Quenching of Tryptophan Phosphorescence in Escherichia Coli Alkaline Phosphatase by Long-Range Transfer Mechanisms to External Agents in the Rapid Diffusion Limit. Biochemistry 30:668-675.