Results 141 to 150 of about 20,124 (183)

Coniferyl alcohol oxidase ? a catechol oxidase?

Trees, 1995
The physico-chemical properties of coniferyl alcohol oxidase (CAO), a copper containing glycoprotein spatiotemporally associated with lignification in conifers, is reported here. By electron paramagnetic resonance spectroscopy, only type 3 copper was indicated in CAO. CAO oxidizes several laccase substrates; however, it is not a blue-copper protein and
PreethiV. Udagama-Randeniya, RodneyA. Savidge   +1 more
openaire   +1 more source

Tyrosinase and Catechol Oxidase

Nature, 1938
THE nature of tyrosinase has been under discussion for a very long time. Raper and his school1, Graubard and Nelson2, and Keilin and Mann3 believe it to be a distinct enzyme, different from catechol oxidase. Onslow and Robinson4, McCance5, and Richter6 believe it to be a catechol oxidase plus o-chinone plus dehydrogenase. Kubowitz7, whose work appeared
L. CALIFANO, D. KERTESZ
openaire   +1 more source

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 Allan, John R L Walker
exaly   +2 more sources

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
openaire   +2 more sources

Tyrosinase Versus Catechol Oxidase: One Asparagine Makes the Difference

Angewandte Chemie - International Edition, 2016
AbstractTyrosinases mediate the ortho‐hydroxylation and two‐electron oxidation of monophenols to ortho‐quinones. Catechol oxidases only catalyze the oxidation of diphenols. Although it is of significant interest, the origin of the functional discrimination between tyrosinases and catechol oxidases has been unclear. Recently, it has been postulated that
Felix Tuczek, Heinz Decker, Even Solem
exaly   +3 more sources

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
openaire   +3 more sources

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

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
openaire   +2 more sources

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
openaire   +2 more sources

Evidence for Conformational Changes in Grape Catechol Oxidase

Phytochemistry, 1972
Abstract A rapid, 4–10-fold, activation of grape catechol oxidase by a short exposure to acid pH or urea is demonstrated. Activation was either reversible or irreversible, depending on length and type of treatment. The change in activity of the enzyme is due primarily to an increase in V max , while the affinity for 4-methylcatechol decreases and ...
E Harel, A M Mayer
exaly   +2 more sources