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Characterization of a Novel 8-Oxoguanine-DNA Glycosylase Activity in Escherichia Coli and Identification of the Enzyme as Endonuclease VIII

September 1, 2000

Author(s)

T. K. Hazra, T. Izumi, R Venkataraman, Y W. Kow, M. Dizdaroglu, Somenath Mitra

8-oxoguanine (G*), induced by reactive oxygen species, is mutagenic because it mispairs with A. The major G*-DNA glycosylase (OGG), namely, OGG1 in eukaryotes, or MutM in Escherichia coli, excises G* when paired in DNA with C, G and T, but not A

Oxidative DNA Damage and Its Potential Use for Monitoring Oxidative Stress

September 1, 2000

Author(s)

M. Dizdaroglu

The Electronic Spectrum of the Prephenate Dianion. An Experimental and Theoretical (MD/QM) Comparison

August 2, 2000

Author(s)

A. E. Roitberg, S. E. Worthington, Marcia J. Holden, M P. Mayhew, Morris Krauss

Prephenate is the product of a Claisen rearrangement of chorismate. The enzyme chorismate mutase (CM from B. subtilis) accelerates the reaction by a factor of 10 6. The standard method for quantifying prephenate measures the electronic absorption spectrum

Cytochrome c at Model Membrane Surfaces: Exploration via Second Harmonic Generation - Circular Dichroism and Surface-Enhanced Resonance Raman Spectroscopy

July 11, 2000

Author(s)

T Petralli-Mallow, Anne L. Plant, M Lewis, J Hicks

The novel nonlinear optical method second harmonic generation-circular dichroism (SHG-CD) has been used to follow the adsorption and redox properties of a peripheral membrane protein horse heart cytochrome c, adsorbed at several model membrane surfaces

Diffusion Bias and Photophysical Dynamics of Single Molecules in Unsupported Lipid Bilayer Membranes Probed with Confocal Microscopy

July 1, 2000

Author(s)

D L. Burden, John J. Kasianowicz

We utilize scanning confocal fluorescence microscopy to interrogate single fluorescent lipid molecules in unsupported planar bilayers. At high photon flux, an optical trapping effect appears that is approximately 100,000 times larger than predicted by

Improving the Cytochrome P450 Enzyme System for Electrode-Driven Biocatalysis of Styrene Epoxidation

July 1, 2000

Author(s)

M P. Mayhew, Vytautas Reipa, Marcia J. Holden, V L. Vilker

Cytochrome P450 enzymes catalyze a vast array of oxidative and reductive biotransformations that are potentially useful for industrial and pharmaceutical syntheses. Factors such as cofactor utilization and slow reaction rates for non-natural substrates

Intersubunit Association Induces Unique Allosteric Dependence of the T127L CRP Mutant on pH

June 20, 2000

Author(s)

Y. Shi, S. Wang, Frederick P. Schwarz

The allosteric activation of the T127->L mutant of 3'-5' cyclic adenosine monophosphate (cAMP) receptor protein (CRP) by cAMP changes from an exothermic, independent two-site bindingmechanism at pH 7.0 to an endothermic, interacting two-site binding

Response to "Comment on 'Reinterpretation of the Spectra of Hydrated Co++: An Ab Initio Study'"

June 15, 2000

Author(s)

H S. Gilson, Morris Krauss

This is a response to comments on a previous paper. Reinterpretation of the Spectra of Hydrated Co++: an ab Initio Study.

The Effect of an Oxidized Gold Substrate on Alkanethiol Self-Assembly

June 1, 2000

Author(s)

John T. Woodward IV, Marlon L. Walker, Curtis W. Meuse, David J. Vanderah, G Poirier, Anne L. Plant

UV cleaned gold substrates incubated in solutions of alkanethiol show islands on the monolayer surface when imaged with non-contact atomic force microscopy (AFM). The height of the islands above the monolayer is approximately twice the height of the

Application of Electromodulated Fluorescence to the Study of the Dynamics of Alexa 488 Fluorophore Immobilized on a Gold Electrode

May 16, 2000

Author(s)

L. Li, Curtis W. Meuse, Vitalii I. Silin, Adolfas Gaigalas, Y. Z. Zhang

Alexa 488 fluorophores was immobilized on a gold electrode. The formation of the layer of fluorophore was followed in real time using surface plasmon resonance (SPR). Both SPR and spectroscopic ellipsometry (SE) gave a thickness of about} 0.7 nm for the

Effective Fragment Potentials and the Enzyme Active Site

May 1, 2000

Author(s)

S E. Worthington, Morris Krauss

Optimization of the binding conformation of a substrate in an enzyme active site using ab initio quantum chemistry methods are intractable since the active site comprises several hundred atoms. However, the active site can be decomposed into an active and

Oxidative DNA Damage; Mechanisms of Product Formation and Repair By Base-Excision Pathway

May 1, 2000

Author(s)

M Miral Dizdar

Free radicals such as OH, e aq- and H atoms react with DNA by addition to bases or abstraction of H atoms from the sugar moiety. Oxygen adds to base or sugar radicals of DNA resulting in formation of peroxyl radicals. DNA radicals further react to give

Spin-Orbit Configuration Interaction Calculation of the Potential Energy Curves of Iodine Oxide

April 6, 2000

Author(s)

S Roszak, Morris Krauss, A B. Alekseyev, H P. Liebermann, R J. Buenker

An ab initio cofiguration interaction (CI) study including spin-orbit coupling is carried out for the ground and excited states of the IO radical by employing relativistic effective core potentials. The computed spectroscopic constants are in good

Differential Surface Stress of a Tin Oxide Electrode

April 1, 2000

Author(s)

Gintaras Valincius, Vytautas Reipa

Differential surface stress measurements performed using estance technique and simultaneous measurements of the differential capacitance provide experimental evidence for deviation of n-tin oxide electrode's properties from the electrocapillary

Interrogating Unsupported Lipid Bilayers With Scanning Confocal Single-Molecule Fluorescence Microscopy

January 23, 2000

Author(s)

D L. Burden, John J. Kasianowicz

We describe the use of scanning confocal fluorescence microscopy to probe the structure and temporal dynamics of unsupported planar lipid bilayer membranes. At high fluorescent label concentration, the shape and stability of the membranes are evaluated

Human Mitochondrial Genetics

January 1, 2000

Author(s)

L A. Tully, Barbara C. Levin

The field of human mitochondrial genetics has advanced way beyond where the Human Genome Project hopes to be by the year 2003, the projected year for completing the sequence of the entire human nuclear DNA genome. Not only has the mitochondrial DNA (mtDNA)

Mapping Oxidative DNA Damage and Mechanisms of Repair

January 1, 2000

Author(s)

H Rodriguez, T. O'Connor, S. A. Akman

Surface stress of tin oxide electrode

January 1, 2000

Author(s)

Gintaras Valincius, Vytautas Reipa

Nonlinear Optics as a Detection Scheme for Biomimetic Sensors: SFG Spectroscopy of Hybrid Bilayer Membrane Formation

December 15, 1999

Author(s)

T Petralli-Mallow, Kimberly A. Briggman, Lee J. Richter, John C. Stephenson, Anne L. Plant

Vibrational spectra of biomimetic membranes have been obtained using a broad-band approach to sum frequency generation (SFG). A new innovation, broad band SFG (BBSFG) allows for high quality SFG spectra with rapid collection times. With the BBSFG approach

Thermal Stability of PNA/DNA and DNA/DNA Duplexes by Differential Scanning Calorimetry

December 15, 1999

Author(s)

M C. Chakrabarti, Frederick P. Schwarz

Thermodynamic quanties describing the hybridizatin reactions for 8mer PNA/DNA duplexes and the corresponding 8mer DNA/DNA duplexes were determined by isothermal titation calorimetry measurements at ambient temperatures. Values of δG b for the DNA/DNA