Xanthine dehydrogenase localization

Newcomb, E.H., Datta, D.B. Triplett, E.W. (1990). Cellular localization of xanthine dehydrogenase (XDH) in root nodules of cowpea (Vigna unguiculata L. Walp). In Nitrogen Fixation Achieve-... 

Triplett, E.W. (1985). Intracellular nodule localization and nodule specificity of xanthine dehydrogenase in soybean. Plant Physiology 77, 1004-9. 

Nguyen, J., and Feierabend, J. (1978). Some properties and subcellular localization of xanthine dehydrogenase in pea leaves. Plant Sci. Lett. 13 125-32. 

Some oxidations are mediated by hepatic enzymes localized outside the microsomal system. Alcohol dehydrogenase and aldehyde dehydrogenase, which catalyse a variety of alcohols and aldehydes such as ethanol and acetaldehyde, are found in the soluble fraction of the liver. Xanthine oxidase, a cytosolic enzyme mainly found in the liver and in small intestine, but also present in kidneys, spleen and heart, oxidizes mercaptopurine to 6-thiouric acid. Monoamine oxidase, a mitochondrial enzyme found in liver, kidney, intestine and nervous tissue, oxidatively deanoinates several naturally occurring amines (catecholamines, serotonin), as well as a number of drugs. 

Figure 3. Compartmentalization of the purine salvage pathway of Leishmania. Abbreviations are as follows AAH, adenine aminohydrolase XPRT, xanthine phosphoribosyltransferase HGPRT, hypoxanthine-guaninephosphoribosyltransferase ADSS, adenylosuccinate synthetase ASL, adenylosuccinate lyase IMPDH, inosine monophosphate dehydrogenase GMPS, gua-nosine monophosphate synthase GDA, guanine deaminase AMPDA, adenosine monophosphate deaminase GMPR, guanosine monophosphate reductase APRT, adenine phosphoribosyltransferase AK, adenosine kinase. Enzymes that have been localized are shown in black and those that are predicted to be in the denoted locations are depicted in gray.

Hydrolases identified include amylases, lipases, esterases, proteinases and phosphatases. Proteinase inhibitors have also been found. Important oxidoreductases in milk are aldehyde dehydrogenase (xanthine oxidase), lactoperoxidase and catalase. A general idea of the occurrence and localization of enzymes in boving milk is given in Table 10.24... 

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