Oxidase enzymes

LUDWIG-MULLER, J., HILGENBERG, W., A plasma membrane-bound enzyme oxidases L-tryptophan to indole-3-acetaldoxime, Physiol. Plant., 1988, 74, 240-250. 

Fig.9 Electrochemical polymerization of pyrrole on the electrode-bound redox enzyme oxidase...

Zinc enzymes Enzymes Oxidases Vitamin B- 2 Not clear Redox enzymes Selenium enzymes... 

Acacia (gum arabic) is a dried gum from the stems and branches of the tree Acacia Senegal (Leguminosae/Fabaceae), abundant in the Sudan and Central and West Africa. Trees are tapped by removing a portion of the bark. The gum is used as a suspending agent, and adhesive and binder for tablets. The carbohydrate is a complex branched-chain material, which yields L-arabinose, D-galactose, D-glucuronic acid, and L-rhamnose on hydrolysis. Occluded enzymes (oxidases, peroxidases, and pectinases) can cause problems in some formulations, unless inactivated by heat. 

Chemiluminescence immunoassay methods have many applications (Weeks, 1992). Highly sensitive chemiluminescent immunoassays were developed by Tsuji et al. (1989) for determination of enzymes (oxidases, peroxidase, glucose oxidase, P-D-galactosidase) as well as various hormones and drugs in biological fluids (Tsuji et al., 1989). 

Rather than adding peroxides that are very thermally stable, ICI researchers added peroxide generating enzymes to PS [25]. These enzymes (oxidases) constantly convert absorbed air to peroxides, which decompose forming radicals that allegedly scavenge the styrene. 

The formation of Cp—Car bonds is illustrated by the generation of dehydrodiisoeugenol (286) from ( )-isoeugenol (257), enzymically with a mushroom juice (45%) yield, with horseradish peroxidase (65%), ° with iron(III) chloride (53%), by photooxidation (20%) and by (-)-a-phenylethylamine-copper(ll) nitrate (21%). In the last case a low enantiomeric excess was recorded. Coniferyl alcohol can be oxidized to dehydrodiconiferyl alcohol (287) with various enzyme oxidases. The cis... 

The many methods to initiate lipid peroxidation in vitro, such as azo initiators, metal ions, pulse radiolysis, photoinitiation (Type I), enzymes (oxidases), to mention a few, have been reviewed . However, as Bucala emphasized in a review ", oxidation initiation is a pivotal first step and there is little understanding of how initiation proceeds in vivo. Transition metal ions, iron or copper, are frequently used to initiate lipid oxidation, but free (unchelated) redox-active transition metals are virtually absent from biological systems" and appear to have little bearing on known pathological processes ". 

The PVC membrane described in this patent acts as a barrier to paracetamol and sugars but it is permeable to hydrogen peroxide. The membrane is used to detect activity of enzyme oxidase which readily forms hydrogen peroxide from glucose. The membrane is made from pure PVC (no additives or plasticizers) by solvent casting to obtain a thickness of 10 to 40 pm. 

Peroxisomes are cell organelles with a diameter of 0.1 -1.0 pm and are bounded by one triple-layered membrane, which is nevertheless thinner than most of the other cellular membranes, for example, the membrane of lysosomes [30, 31]. Originally, only the enzymes oxidase and catalase were known to exist in the matrix of peroxisomes and therefore it was suggested that peroxisomes are organelles of hydrogen peroxide production and degradation [30]. With... 

Scheme 5.2 (a) Mediated Mo enzyme (reductase) electrochemistry and (b) direct Mo enzyme (oxidase/dehydrogenase) electrochemistry. 

In tissues, copper is associated either with noncataly-tic proteins or with specific enzymes—oxidase, phenol-oxidase, ascorbic acid oxidase, uricase, and also cytochrome oxidase (see section on electron transport). These copper enzymes usually have an absorption maximum between 320 and 330 mp, and when exposed to oxygen, they develop a sharp absorption band at approximately 600 mp. This intense absorption of the oxygen complex is explained by charge transfer between metal and oxygen ... 

The enzymes (oxidases) primarily responsible for oxidation are tyrosinase and laccase, both present in the grape berry, although the latter is specific to Botrytis cinerea and thus is only present in berries and, therefore, must and juice affected by Botrytis. The oxidases catalyse the transfer of oxygen to phenolic substrates in the juice. 

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