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标题：Ascorbic acid sulfate sulfohydrolase (C2 sulfatase): the modulator of cellular levels of L-ascorbic acid in rainbow trout
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作者：L V Benitez ; J E Halver
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1982
卷号：79
期号：18
页码：5445-5449
DOI：10.1073/pnas.79.18.5445
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The enzyme L-ascorbic acid 2-sulfate sulfohydrolase (C2 sulfatase) was purified from rainbow trout liver. The enzyme catalyzes the hydrolysis of L-ascorbic acid 2-sulfate and has a pH optimum at 6.0. It has a molecular weight of about 117,500 at pH 5.0 and is inhibited by a number of sulfhydryl blocking agents including L-ascorbic acid. C2 sulfatase activity was observed in most metabolic organs of rainbow trout. These findings suggest that the physiologic role of the enzyme is to maintain adequate cellular concentrations of L-ascorbic acid in the fish. The activity of the enzyme is controlled by L-ascorbic acid through feedback inhibition. Comparison of kinetic constants and inhibition patterns suggests that C2 sulfatase is structurally identical to human arylsulfatase A. However, unlike C2 sulfatase, human arylsulfatase A may not be involved in ascorbate metabolism. Its physiologic substrate is reported to be cerebroside-3-sulfate, not L-ascorbic acid 2-sulfate. A scheme is proposed to account for the functional divergence of these two structurally identical enzymes.