A SPECIFIC TETRAHYDROBIOPTERIN BINDING DOMAIN ON TYROSINASE CONTROLS MELANOGENESIS

被引：62

作者：

WOOD, JM ^{[1
]}

SCHALLREUTERWOOD, KU ^{[1
]}

LINDSEY, NJ ^{[1
]}

CALLAGHAN, S ^{[1
]}

GARDNER, MLG ^{[1
]}

机构：

[1] UNIV HAMBURG,DEPT DERMATOL,HAMBURG,GERMANY

来源：

BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS | 1995年 / 206卷 / 02期

关键词：

D O I：

10.1006/bbrc.1995.1068

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

(6R)5,6,7,8-tetrahydrobiopterin (6-BH4) directly regulates tyrosinase activity by specifically binding to a putative 13 amino acid domain. This domain has sequence homology to 6-BH4 binding sites already identified on phenylalanine hydroxylase and 4a-carbinolamine dehydratase. Furthermore, this binding sequence appears to have been conserved during the evolution of tyrosinase as it has also been identified in the frog, mouse and human enzymes. 6-BH4 controls tyrosinase activity by an uncompetitive mechanism requiring the presence of L-tyrosine for effective down-regulation. When L-dopa is substrate, 6-BH4 does not inhibit the enzyme implicating separate binding sites for L-dopa and L-tyrosine on tyrosinase. Dihydropterin and 6-biopterin, the oxidation products of 6-BH4, do not inhibit tyrosinase significantly, indicating that melanin biosynthesis is controlled by a 6-BH4/6-biopterin redox-switch mechanism which can be initiated by photo-oxidation of 6-BH4. (C) 1995 Academic Press, Inc.

引用

页码：480 / 485

页数：6

共 10 条

[1] 7-TETRAHYDROBIOPTERIN, A NATURALLY-OCCURRING ANALOG OF TETRAHYDROBIOPTERIN, IS A COFACTOR FOR AND A POTENTIAL INHIBITOR OF THE AROMATIC AMINO-ACID HYDROXYLASES [J].