HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Watt, W. B. Search for Related Content PubMed PubMed Citation Articles by Watt, W. B. Social Bookmarking                      What's this?

Xanthine Dehydrogenase and Pteridine Metabolism in Colias Butterflies

From the ¹ From the Department of Biological Sciences, Stanford University, Stanford, California 94305

It is shown that an enzyme from Colias butterflies, oxidizing the yellow pteridine xanthopterin to the colorless pteridine leucopterin, is in fact xanthine dehydrogenase. Methods for the partial purification of the enzyme are given. The enzyme oxidizes a number of purines and pteridines effectively, with NAD⁺ as cosubstrate. It is inhibited competitively by its products of reaction, leucopterin and uric acid, and by the precursor of xanthopterin, 7,8-dihydroxanthopterin. A model is constructed for the regulation of portions of the Colias pteridine pathway during ontogeny, incorporating both product and "feed forward" inhibition of xanthine dehydrogenase as shown here.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?