Sundaram K S, Lev M
Department of Microbiology, CUNY Medical School, New York 10031.
Biochem Biophys Res Commun. 1990 Jun 29;169(3):927-32. doi: 10.1016/0006-291x(90)91982-x.
Previous work has shown that vitamin K regulates brain sulfotransferase activity. We now show that activity is lost after treatment with acid phosphatase and is restored with ATP. Orthophosphate activates sulfotransferase to a small degree (26%) with a maximum at 3 mM. Vitamin K1 (or menadione) + orthophosphate stimulates activity 400%; vitamin K alone is not active. ATP activates maximally at 10 mM; ATP + vitamin K increases activation 20%. Protein kinase inhibitors do not affect ATP or orthophosphate + vitamin K mediated activation. Sulfotransferase is inhibited by pyridoxal phosphate indicating modification of a lysyl residue.
先前的研究表明维生素K可调节脑磺基转移酶的活性。我们现在发现,用酸性磷酸酶处理后该活性丧失,而用ATP可使其恢复。正磷酸盐在3 mM时能使磺基转移酶活性有小幅度激活(26%),激活程度最大。维生素K1(或甲萘醌)+正磷酸盐可使活性提高400%;单独的维生素K无活性。ATP在10 mM时激活作用最大;ATP +维生素K可使激活作用增加20%。蛋白激酶抑制剂不影响ATP或正磷酸盐+维生素K介导的激活作用。磷酸吡哆醛可抑制磺基转移酶,这表明有一个赖氨酰残基发生了修饰。