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Tandem Isotachophoresis-Zone Electrophoresis via Base-Mediated Destacking for Increased Detection Sensitivity in Microfluidic Systems

May 21, 2003

Author(s)

Wyatt N. Vreeland, S J. Williams, A E. Barron, A P. Sassi

Crystal Structure of the Escherichia Coli YcdX Protein Reveals a Trinuclear Zinc Active Site

May 1, 2003

Author(s)

A Teplyakov, G Obmolova, P P. Khil, A J. Howard, R D. Camerini-Otero, G L. Gilliland

The ycdX gene of Escherichia coli encodes the protein of 27 kDa molecular weight that belongs to the PHP superfamily of proteins that have diverse functions. This superfamily includes several types of DNA polymerases (namely the a-subunit of bacterial DNA

Evaluation of Extraction Methodologies for Corn Kernal (Zea Mays) DNA for Detection of Trace Amounts of Biotechnology-Derived DNA

April 23, 2003

Author(s)

Marcia J. Holden, J L. Blasic, L Bussjaeger, C Kao, Luke A. Shokere, D C. Kendall, L Freese, G. Ronald Jenkins

Sensitivity and accurate testing for trace amounts of biotechnology-derived DNA from plant material requires pure, high-quality genomic DNA as template for subsequent amplification using the polymerase chain reaction (PCR). Six methodologies were evaluated

Choosing a Cantilever for In Situ Atomic Force Microscopy

April 1, 2003

Author(s)

John T. Woodward IV

This manuscript is a non-peer reviewed, invited tutorial for Microscopy Today. It describes the issues involved in choosing a cantilever for atomic force microscope (AFM) imaging under fluids. In situ AFM imaging is an increasingly popular technique for

Comparison of Reagents for Shape Analysis of Fixed Cells by Automated Fluorescence Microscopy

April 1, 2003

Author(s)

John T. Elliott, Alessandro Tona, Anne L. Plant

Background: Cell size and shape have been implicated as potentiators intracellular signaling events and as indicator of abnormal cell behavior. Automated microscopy and image analysis can provide quantitative information about the size and shape of

Primary Fibroblasts of Cockayne Syndrome Patients Are Defective in Cellular Repair of 8-Hydroxyguanine and 8-Hydroxyadenine Resulting From Oxidative Stress

April 1, 2003

Author(s)

J Tuo, Pawel Jaruga, H Rodriguez, V. Bohr, Miral M. Dizdar

Cockayne Syndrome (CS) is a genetic human disease with clinical symptoms that include neurodegeneration and premature aging. We show that primary fibroblasts from CS patients lack the ability to efficiently repair oxidative DNA damage. Primary fibroblasts

Arabidopsis Thaliana Ogg1 Protein Excises 8-Hydroxyguanine and 2,6- Diamino-4-hydroxy-5-formamidopyrimidine from Oxidative Damaged DNA Containing Multiple Lesions

March 18, 2003

Author(s)

T Morales-Ruiz, M Birincioglu, Pawel Jaruga, H Rodriguez, T. Roldan-Arjona, Miral M. Dizdar

A functional homologue of eukaryotic Ogg1 proteins in the model plant Arabidopsis thaliana has recently been cloned, isolated, and characterized [Garcia-Ortiz, M.V., Ariza, R.R., and Roldan-Arjona, T. (2001) Plant Mol. Biol. 47, 795-804]. This enzyme

Thin Films of Collagen Affect Smooth Muscle Cell Morphology

March 4, 2003

Author(s)

John T. Elliott, Alessandro Tona, John T. Woodward IV, P L. Jones, Anne L. Plant

The purpose of this study was to provide a reproducible method for applying collagen to surfaces on which cells can be grown, and to characterize the resulting thin films of collagen protein with respect to molecular structure and cellular response

Thermodynamics of Enzyme-Catalyzed Reactions

March 1, 2003

Author(s)

Robert N. Goldberg, Yadu D. Tewari

This review, which has been prepared for the McGraw-Hill 2003 Yearbook of Science and Technology, gives an overview of the thermodynamics of enzyme-catalyzed reactions. Topics include the thermodynamic formalism(s) used in this field, computational methods

Binding and Hydrolysis of Ampicillin in the Active Site of a Zinc Lactamase

February 6, 2003

Author(s)

Morris Krauss, N. Gresh, J Antony

Binding and hydrolysis of ampicillin is described in a model active site derived from di-nuclear B.fragilis zinc lactamase. The protein binding site consists of the two zinc cations bound with a bridging hydroxide and ligands from the first-shell residues

Evidence for Structural Changes in Carboxyl-Terminal Peptides of Transducin Alpha-Subunit Upon Binding a Soluble Mimic of Light-Activated Rhodopsin

January 21, 2003

Author(s)

D M. Brabazon, N G. Abdulaev, John Marino, K D. Ridge

Although a high-resolution crystal structure for the ground state of rhodopsin is now available, portions of the cytoplasmic surface are not well resolved and the structural basis for the interaction of the cytoplasmic loops with the retinal G-protein

Biomarkers Used to Detect Genetic Damage in Tissue-Engineered Skin

January 1, 2003

Author(s)

C D. O'Connell, Peter E. Barker, M A. Marino, P McAndrew, Donald H. Atha, Pawel Jaruga, M Birincioglu, M. Dizdaroglu, H Rodriguez

The goal of the research was to help identify cellular biomarkers and assess measurement technologies that will help manufacturers determine how cells react to inflammatory stimuli from different polymer matrixes and assure that tissue-engineered medical

Comparative Electronic Structure of a Lanthanide and Actinide Diatomic Oxide: Nd versus U

January 1, 2003

Author(s)

Morris Krauss, W J. Stevens

Using a modified version of the ALCHEMY electronic structure code and relativistic pseudopotentials, the electronic structure of the ground and low-lying excited states of UO, NdO, and NdO+ have been calculated at the Hartree-Fock (HF) and

Fluorescence Resonance Energy Transfer Between Donor-Acceptor Pair on Two Oligonucleotides Hybridized Adjacently to a DNA Template

January 1, 2003

Author(s)

Lili Wang, Adolfas K. Gaigalas, J L. Blasic, Marcia J. Holden, David T. Gallagher, R Pires

We have used fluorescein as the energy donor and rhodamine as the acceptor to measure the efficiency of fluorescence resonance energy transfer (FRET) in a set of hybridized DNA constructs. The two fluorophores are covalently attached via linkers to two

High-Throughput Analysis of Telomerase by Capillary Electrophoresis

January 1, 2003

Author(s)

Donald H. Atha, K Miller, A D. Sanow, J Xu, J L. Hess, O C. Wu, Wenhua Wang, S Srivastava, W E. Highsmith

The enzyme telomerase is expressed in 85-90% of all human cancers, but not in normal, non-stem cell somatic tissues. Clinical assays for telomerase in easily obtained body fluids would have great utility as non-invasive, cost-effective methods for the

Oxidative DNA Damage Biomarkers Used in Tissue Engineered Skin

January 1, 2003

Author(s)

H Rodriguez, Pawel Jaruga, M Birincioglu, Peter E. Barker, C D. O'Connell, M. Dizdaroglu

To assure that tissue engineered medical products are free of genetic changes that might occur from inflammation during the development phase of the product, our laboratory is responding to the need for test methods used to assess the safety and

The Influence of Agarose Concentration in Gels on the Electrophoretic Trapping of Circular DNA

January 1, 2003

Author(s)

Kenneth D. Cole, B. Akerman

The concentration of agarose in electrophoresis gels was found to have significant effects on the apparent density and release characteristics of the electrophoretic traps for circular DNA. Agarose gels were cast in a range of concentrations from 0.25% to

Local Protein Dynamics and Catalysis: Detection of Segmental Motion Associated With Rate-Limiting Product Release by a Glutathione Transferase

December 24, 2002

Author(s)

S G. Codreanu, Jane E. Ladner, G Xiao, N V. Stourman, D L. Hachey, G L. Gilliland, R N. Armstrong

Glutathione transferase rGSTM1-1 catalyzes the addition of glutathione (GSH) to 1-chloro-2,4-dinitrobenzene in which chemical step of the reaction is 60-fold faster than the physical step of product release. The hydroxyl group of Y115, located in the

The role of surface free energy on the formation of hybrid bilayer membranes

December 11, 2002

Author(s)

Vitalii I. Silin, H Wieder, John T. Woodward IV, Gintaras Valincius, A Offenhausser, Anne L. Plant

Design and Use of a Peptide Nucleic Acid for Detection of the Heteroplasmic Low-Frequency Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-Like Episodes (MELAS) Mutation in Human Mitochondrial DNA

December 1, 2002

Author(s)

Diane K. Hancock, Frederick P. Schwarz, F H. Song, L J. Wong, Barbara C. Levin

Most pathogenic human mitochondrial DNA (mtDNA) mutations are Heteroplasmic and are difficult to detect when present at very low levels in a population of normal mtDNA molecules. This paper describes a simple methodology to detect low levels of the single

Thermodynamic Quantities for the Ionization Reactions of Buffers in Water

December 1, 2002

Author(s)

Robert N. Goldberg, N Kishore, R M. Lennen

This table contains selected values for the pK, standard molar enthalpy of reaction {Δ} rH , and standard molar heat-capacity change {Δ} rC p for the ionization reactions of 64 buffers many of which are relevant to biochemistry and to biology. The values

Reaction Mechanism of Chorismate Mutase Studied by the Combined Potentials of Quantum Mechanics and Molecular Mechanics

November 21, 2002

Author(s)

Y. S. Lee, S. E. Worthington, Morris Krauss, B R. Brooks

The reaction path for the rearrangement of chorismate to prephenate has been determined in a QM/MM study including the entire protein environment while treating the reaction with ab initio quantum chemistry. In addition to the reactant, chorismate, the

Nanometer-Scale Pores: Potential Applications for Analyte Detection and DNA Characterization

October 1, 2002

Author(s)

John J. Kasianowicz

Several classes of transmembrane protein ion channels function in vivo as sensitive and selective detection elements for analytes. Recent studies on single channels reconstituted into planar lipid bilayer membranes suggest that nanometer-scale pores can be

Importance of Product Inhibition in the Kinetics of the Acylase Hydrolysis Reaction by Differential Stopped Flow Microcalorimetry

September 15, 2002

Author(s)

M Stodeman, Frederick P. Schwarz

The hydrolysis of N-acetyl-L-methionine, N-acetylglycine, N-acetyl-L-phenylalanine, and N-acetyl-L-alanine at 298.35 K by porcine kidney acylase I (EC 3.5.1.14) was monitored by the heat released upon mixing of the substrate and enzyme in a differential

The Cockayne Syndrome Group B Gene Product is Involved in Cellular Repair of 8-Hydroxyadenine in DNA

August 23, 2002

Author(s)

J Tuo, Pawel Jaruga, H Rodriguez, Miral M. Dizdar, V. Bohr

Cockayne syndrome (CS) is a human disease characterized by sensitivity to sunlight, severe neurological abnormalities and accelerated aging. CS has two complementation groups, CS-A and CS-B. The CSB gene encodes the CSB protein with 1493 amino acids. We