Lipoxygenase, type

Soybean lipoxygenase, type 1, 170,000 units/mg protein (Sigma Chemicals)... 

Lipoxygenase oxidizes the unsaturated fatty acids in the oU in the seeds during storage under the conditions described above (48). There are different types of lipoxygenases in oilseeds. Lipoxygenase- Type-11 and Type-lV are more reactive than... 

Soybean lipoxygenase (type I), a-linolenic acid (99%), y-linolenic acid (99%), dtono-y-linolenic acid, arachidonic acid (99 %), hemoglobin (type I, bovine 75%), sodium bordiydride, sodium cholate, Detapac, Brij 56 and DEAE-Sephacd were products of Sigma Chemical Co. 

An excellent classification of this type of enzymes was that of Burton (2003). Because of their importance in polyphenol degradation, we have studied four enzymes closely related with the oxidation of phenolic compounds polyphenoloxidase, peroxidase, laccase, and lipoxygenase. 

Kausch KD, Handa AK. Molecular cloning of a ripening-specific lipoxygenase and its expression during wild-type and mutant tomato fruit development. Plant Physiol 1997 113 1041-1050. 

Finally there has been a growing interest in the development of selective leukotriene inhibitors. Bay Y 1015 (R-(-)-2-cycloheptyl-N-methylsulfonyl-(4-(2-quinolinyl-methoxy) phenyl)-acetamide) is a quinoline-type 5-lipoxygenase-activating protein inhibitor which was effective in inhibiting inflammation in a dextran sulfate model of mouse colitis [112]. Whether these compounds can also exert their anti-inflammatory action through inhibition of endothelial cell activation needs to be established. 

The assays presented in this section deal with the measurement of enzyme activity, which is expected to be proportional to the amount of active enzyme present in a sample, food or otherwise, unit ci.i is an overview of the important considerations in performing activity assays unitc 1.2 illustrates how these considerations are applied to the assay of a representative food-relevant glycosyl hydrolase. Chapters C2, C3, and C4 present the first units on particular types of activity assays. In Chapter C2, two units present peptidase activity assays that use either synthetic substrates (UNITC2.1) or common, commercially available protein substrates (unit C2.2). unitC3.i presents three different assays for lipase activity. unitc4.i presents assays for diphenol oxidases, and unitc4.2 for lipoxygenase. 

Lehmann, W.D. 1994. Regio- and stereochemistry of the dioxygenation reaction catalyzed by (S)-type lipoxygenases or by the cyclooxygenase activity of prostaglandin H synthases. Free Radical Biol. Med. 16 241-253. 

Gu, J.L., Pei, H., Thomas, L., Nadler, J.L., Rossi, J.J., Lanting, L. and Natarajan, R. (2001) Ribozyme-mediated inhibition of rat leukocyte-type 12-lipoxygenase prevents intimal hyperplasia in balloon-injured rat carotid arteries. Circulation, 103, 1446-1452. 

Moody, J. S., Kozak, K. R., Ji, C., and Marnett, L.J. (2001). Selective oxygenation of the endocanna-binoid 2-arachidonylglycerol by leukocyte-type 12-lipoxygenase. Biochemistry 40, 861—866. 

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