Results 161 to 170 of about 19,268 (196)

Theoretical study of the catalytic mechanism of catechol oxidase

JBIC Journal of Biological Inorganic Chemistry, 2007
The mechanism for the oxidation of catechol by catechol oxidase has been studied using B3LYP hybrid density functional theory. On the basis of the X-ray structure of the enzyme, the molecular system investigated includes the first-shell protein ligands of the two metal centers as well as the second-shell ligand Cys92.
Mireia, Güell, Per E M, Siegbahn
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Substrate Binding in Catechol Oxidase Activity:  Biomimetic Approach

Inorganic Chemistry, 2002
A series of dicopper(II) complexes have been investigated as model systems for the catechol oxidase active site enzyme, regarding the binding of catechol substrate in the first step of the catalytic cycle. The [Cu(2)(L(R))(mu-OH)](ClO(4))(2) and [Cu(2)(L(R))(H(2)O)(2)](ClO(4))(3) complexes are based on the L(R) ligands (2,6-bis[(bis(2-pyridylmethyl ...
Torelli, Stephane, Belle, Catherine, Hamman, Sylvain, Pierre, Jean-Louis, Saint-Aman, Eric   +4 more
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New functional models for catechol oxidases

Inorganica Chimica Acta, 2000
The new dinuclear copper(II) complexes [Cu2(L1)(m-OAc)](ClO4)2·CH3CN (1), [Cu2(L2)(CH3CN)2](ClO4)4·C2H5OH (2), [Cu2(L3)2(CH3CN)2](PF6)2 (3) and [Cu2(L4)2](PF6)2·2CH2Cl2 (4) were prepared with the ligands N,N,N%,N%-tetrakis((N-2-hydroxyethyl)-2-benzimidazolylmethyl)-2-hydroxy-1,3-diaminopropane HL1, N,N,N%,N%-tetrakis (2-methylimidazolyl)-2-hydroxy-1,3 ...
Pavel Gentschev, Niclas Möller, Bernt Krebs   +2 more
openaire   +1 more source

Olive catechol oxidase ‐ changes during fruit development

Journal of the Science of Food and Agriculture, 1977
AbstractChanges were recorded in the subcellular location of catechol oxidase. In the green olive the enzyme is tightly bound to the chloroplast whereas in the black fruit it is essentially soluble. During fruit development, enzyme activity per fruit declines while the o‐diphenolic content rises steadily.
N, Ben-Shalom, V, Kahn, E, Harel, A M, Mayer   +3 more
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Catechol oxidases, endogenous substrates and browning in developing apples

Journal of the Science of Food and Agriculture, 1966
AbstractThe content of o‐diphenols and catechol oxidase activity was followed in developing apples from fruit set to harvest time. Afterwards their level drops, apparently due to conversion to other compounds and cessation of synthesis. Catechol oxidase activity shows a peak after that occurring in content of o‐diphenols.
E, Harel, A M, Mayer, Y, Shain
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Catechol oxidase of red delicious apple peel

Phytochemistry, 1972
Abstract Catechol oxidase has been solubilized from the particulate fraction of apple peel using Triton X-100, dialysis and butanol extraction. The partially purified enzyme retained activity during lyophilization in the presence of mercaptobenzothiazole. The substrate specificity and pH optima of the enzyme are reported.
David A. Stelzig, S. Akhtar, S. Ribeiro
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Synthetic models of the active site of catechol oxidase: mechanistic studies

Chemical Society Reviews, 2006
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Koval, Iryna, Gamez, Patrick, Belle, Catherine, Selmeczi, Katalin, Reedijk, Jan   +4 more
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The selective inhibition of catechol oxidases by salicylhydroxamic acid.

Phytochemistry, 1988
Abstract Salicylhydroxamic acid (SHAM) has been shown to be a powerful and selective inhibitor of catechol oxidases but was without effect on laccases.
Andrew C. Allan, John R.L. Walker
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Partial purification and properties of catechol oxidases in grapes

Phytochemistry, 1971
Abstract Grapes contain a high level of catechol oxidase activity. The enzyme is located in a particulate fraction of the cell, apparently in the plastids. It resembles catechol oxidases from other fruits in many aspects but differs in its relatively high activity towards caffeic and p-hydroxycinnamic acids and in its high affinity towards the latter.
E. Harel, A.M. Mayer
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Multiple forms of Vitis vinifera catechol oxidase

Phytochemistry, 1973
Abstract Grape catechol oxidase shows multiple forms upon ion exchange chromatography, acrylamide gel electrophoresis and gel filtration. Conversion of some bands into others, which occurs during isolation and storage, is enhanced by dilution and by treatment with urea or acid pH.
Eitan Harel, Alfred M. Mayer, Eliakim Lehman   +2 more
openaire   +1 more source