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Cerebral hydroxylases: stimulation by a new factor.

E M Gàl·A E Roggeveen
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Abstract

Cerebral tryptophan 5-hydroxylase and tyrosine hydroxylase are stimulated by a solution of lyophilized, protein-free 30,000g supernatant of brain homogenates (concentrate 1). This preparation can be further purified by passage through Sephadex G-75 and phosphocellulose columns to yield concentrate 2. Unlike concentrate 1, concentrate 2 is unstable after several days of storage even at -27 degrees C. Neither preparation is active without the presence of a reduced pteridine cofactor. The stimulating factor appears to be thermostable, alkali-labile, dialyzable, and light-sensitive.

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AlkaliesAnimalsBorohydridesBrainBrain ChemistryCarbon IsotopesChromatography, GelDialysisDopamineEnzyme InductionHot TemperatureMercaptoethanolMixed Function OxygenasesPhotolysisPteridinesPterinsRatsTissue ExtractsTryptaminesTryptophan HydroxylaseTyrosine 3-MonooxygenaseJournal Article

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E M Gàl, A E Roggeveen. 1973-02-23. Cerebral hydroxylases: stimulation by a new factor.. https://doi.org/10.1126/science.179.4075.809

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