Results 331 to 340 of about 2,040,864 (360)

Models for hemoglobin and allosteric enzymes

Biopolymers, 1968
AbstractA model for hemoglobin is proposed and its application to allosteric enzymes is discussed with particular reference to asparate transcarbamylase. The main assumptions made are that the molecule is composed of subunits and that occupation of a sub‐unit produces a conformational change which affects the occupational probability of neighboring ...
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Dihydroorotase from Clostridiumoroticum is an allosteric enzyme

Biochemical and Biophysical Research Communications, 1979
Abstract Dihydroorotase from Clostridium oroticum exhibits allosteric behavior with respect to both of its substrates. L-dihydroorotate dependence reflects a positive homotropic interaction for which the Hill coefficient is 1.3–1.6, depending upon the preparation.
Eugene G. Sander, Jane Ma, Julie E. Scheffler   +2 more
openaire   +3 more sources

Evidence for two different mechanisms triggering the change in quaternary structure of the allosteric enzyme, glucosamine-6-phosphate deaminase.

Biochemistry, 2005
The generation and propagation of conformational changes associated with ligand binding in the allosteric enzyme glucosamine-6-phosphate deaminase (GlcN6P deaminase, EC 3.5.99.6) from Escherichia coli were analyzed by fluorescence measurements.
I. Bustos-Jaimes, Montserrat Ramírez-Costa, Lorena De Anda-Aguilar, Pilar Hinojosa-Ocaña, M. Calcagno   +4 more
semanticscholar   +1 more source

Trapping specific quaternary states of the allosteric enzyme aspartate transcarbamoylase in silica matrix sol-gels.

Journal of the American Chemical Society, 2003
The extreme T and R quaternary structures of the allosteric enzyme aspartate transcarbamoylase have been trapped by encapsulation in a silica sol-gel matrix.
Jay M. West, E. Kantrowitz
semanticscholar   +1 more source

Yeast chorismate and other allosteric enzymes

Pure and Applied Chemistry, 1998
Abstract
William N. Lipscomb, Norbert Sträter
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Quantitative evaluation of protein-protein and ligand-protein equilibria of a large allosteric enzyme by electrospray ionization time-of-flight mass spectrometry.

Rapid Communications in Mass Spectrometry, 1998
A mass spectrometer coupling electrospray ionization with time-of-flight mass spectrometry (ESI-TOFMS) has been used to investigate the oligomeric species of Escherichia coli citrate synthase, and to determine the effect of nicotinamide adenine ...
A. Ayed, A. Krutchinsky, W. Ens, K. Standing, H. Duckworth   +4 more
semanticscholar   +1 more source

Structure of the Allosteric Regulatory Enzyme of Purine Biosynthesis

Science, 1994
Multiwavelength anomalous diffraction (MAD) has been used to determine the structure of the regulatory enzyme of de novo synthesis of purine nucleotides, glutamine 5-phosphoribosyl-1-pyrophosphate (PRPP) amidotransferase, fromBacillus subtilis. This allosteric enzyme, a 200-kilodalton tetramer, is subject to end product regulation by purine nucleotides.
Robert L. Switzer, Janet L. Smith, Jean Pierre Wery, Jean Pierre Wery, Yoshinori Satow, Howard Zalkin, Liwen Niu, Liwen Niu, Eugene J. Zaluzec, Eugene J. Zaluzec   +9 more
openaire   +3 more sources

The Kinetics of Allosteric Enzymes

1977
Many important enzymes are oligomeric in structure, being more or less stable associations of smaller units, called protomers, each of which may have one or more than one active site. By comparing these enzymes with monomeric enzymes that have branched mechanisms, it can be seen intuitively that the possibility of binding substrate at more than one ...
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Allosteric properties of enzymes with “ping-pong” mechanism

Biochimica et Biophysica Acta (BBA) - Enzymology, 1972
Abstract Allosteric properties of enzymes exhibiting the ping-pong mechanism, which is characterized by the oscillation of enzyme protein between multiple stable enzyme forms during reaction, have been analyzed in terms of the partial equilibrium theory recently introduced by Cha ( J. Biol. Chem. , 243 (1968) 820).
Takahiko Sumi, Michio Ui
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Insulysin: An Allosteric Enzyme As a Target for Alzheimer's Disease

Journal of Molecular Neuroscience, 2005
That the zinc metalloendopeptidase insulysin (insulin-degrading enzyme IDE) is a major b-amyloid (A(beta)) peptide-degrading enzyme in vivo is shown by the higher A(beta) peptide levels in the brain of an insulysin-deficient mouse. Insulysin was shown to initially cleave A(beta)1-40and A(beta)1-42 at His13-Gln14, His14-Gln15, and Phe19-Phe20.
Eun Suk Song, Louis B. Hersh
openaire   +3 more sources