Energy-Dependent Transport of Urate and Xanthine in the Unicellular Green Alga Chlamydomonas Reinhardtii
Purines and purine derivatives are utilized by many organisms as sources of nitrogen and energy or as precursors in nucleic acids synthesis. Prior to their utilization these compounds must enter the cells through different transport systems depending on the type of cells. Up to now it has been very hard to distinguish between the transport process proper and the subsequent enzymatic oxidation of the transported substrate, since purines and other nucleic acids breakdown products have been observed to be utilized immediately after their transport into the cells. Thus, it is small wonder that there are so few reports in which these transport systems are distinguished from the subsequent metabolism of these compounds (Syrett, 1981; Munch-Petersen and Mygind, 1983).
KeywordsChloral Hydrate Proton Motive Force Unicellular Green Alga Xanthine Dehydrogenase Urate Oxidase
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