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Endonuclease VIII (Nei) is one of three enzymes in Escherichia coli that are involved in base-excision repair of oxidative damage to DNA. We investigated the substrate specificity and excision kinetics of this DNA glycosylase for bases in DNA that have
We describe a technique for the measurement of fluid temperatures in microfluidic systems based on temperature-dependent fluorescence. The technique is easy to implement with a standard fluorescence microscope and CCD camera. The efficiency of the method
Sathyavelu K. Reddy, M A. Kamireddi, K. Dhanireddi, L. Young, A M. Davis, Prasad T. Reddy
We have cloned a cya gene from a human pathogen Mycobacterium tuberculosis H37Rv by complementation of catabolic defect. (Accession No. AF017731, 1977). M. tuberculosis H37Rv genome sequence revealed five genes (Rv1264, Rv1318c, Rv1319c, Rv1320c, and
The Formamidopyrimidine N-DNA glycosylase (Fpg protein) of Escherichia coli is a DNA repair enzyme that is specific for the removal of purine-derived lesions from DNA damaged by free radicals and other oxidative processes. We investigated the effect of
David T. Gallagher, M P. Mayhew, Marcia J. Holden, A J. Howard, K J. Kim, V L. Vilker
The enzyme chorismate lyase (CL) catalyzes the removal of pyruvate from chorismate to produce 4-hydroxy benzoate (4HB) for the ubiquinone pathway. In Escherichia coli, CL is monomeric with 164 residues; we have determined the structure of the CL product
8-Hydroxyadenine (8-OH-Ade) is one of the major lesions, which is formed in DNA by hydroxyl radical attack on the C-8 position of adenine followed by oxidation. We describe the measurement of the nucleoside form of this compound, 8-hydroxy-2'
Lili Wang, A. E. Roitberg, Curtis W. Meuse, Adolfas K. Gaigalas
Raman and FTIR transform-infra red (FT-IR) spectroscopies of fluorescein in aqueous solutions have been investigated in the pH range from 9.1 to 5.4. At pH 9.1 fluorescein is in the dianion form. At pH 5.4, fluorescein is a mixture of monoanion (
Metallolactamase active site structures are examined theoretically for clues to the differences in the enzyme active site observed in different organisms. We will show that the inherent behavior of this type of active site yields a relatively flat
The structure of the active site of human glyoxalase I and the reaction mechanism of the enzyme-catalyzed conversion of the thiohemiacetal, formed from methylglyoxal and glutathione, to S-D-lactoylglutathione has been investigated by ab initio quantum
The reaction path for the rearrangement of chorismate to prephenate, catalyzed by chorismate mutase, has been calculated with ab initio quantum chemistry. The calculation of a reaction path is initiated from two catalytically competent conformations of the
M. B. Esch, Laurie E. Locascio, Michael J. Tarlov, R. A. Durst
This paper describes a microfluidic chip that enables the detection of viable Cryptosporidium parvum by detecting RNA amplified by nucleic-acid sequence-based amplification (NASBA). The mRNA serving as the template for NASBA is produced by viable C. parvum
The calculated reaction path for an unusual substrate of chorismate mutase (Bacillus.subtilis) is found to be completely comparable to that of the native chorismate. In the unusual substrate, the cyclohexadienyl ring in chorismate is replaced by
Residual dipolar couplings can provide powerful restraints for determination and refinement of the solution structure of macromolecules. The application of these couplings in nucleic acid structure elucidation can have an especially dramatic impact since
In November 2000, NIST hosted a workshop on Measurement Traceability for Clinical Laboratory Testing and In Vitro Diagnostic Devices. One of the driving forces was the new European Community (EC) In Vitro Diagnostic Devices (IVDD) directive that requires
The physical nature of the catalytic activity exerted by various ribonuclease A active site constituents is analyzed in terms of the differential transition state stabilization approach in which activation barrier changes induced by the molecular