Sanchez-Amat A, Solano F
Department of Genetics and Microbiology, University of Murcia, Spain.
Biochem Biophys Res Commun. 1997 Nov 26;240(3):787-92. doi: 10.1006/bbrc.1997.7748.
The recently characterized marine melanogenic bacterium MMB-1 contains a pluripotent polyphenol oxidase (PPO) which catalyzes the oxidation of a very wide range of substrates considered specific for tyrosinase or laccase. This range includes monophenols such as L-tyrosine, o-diphenols such as L-dopa, p-diphenols such as hydroquinone, o-aminophenols such as 3-hydroxyanthranilic acid, activated monophenols such as 2,6-dimethoxyphenol and syringaldazine, and chromophores such as ABTS. This is the first report of an enzyme that is able to catalyze the oxidation of compounds so far considered specific for tyrosinases (L-tyrosine) or laccase (syringaldazine), showing cresolase, catechol oxidase and laccase activities. Such PPO could be a very useful model to study the structural requirements, catalytic mechanisms and involvement of the copper sites existing in non-blue and blue copper-oxidases.
最近鉴定出的海洋产黑色素细菌MMB-1含有一种多能多酚氧化酶（PPO），它能催化氧化一系列被认为是酪氨酸酶或漆酶特异性底物的物质。这些底物包括单酚类如L-酪氨酸、邻二酚类如L-多巴、对二酚类如对苯二酚、邻氨基酚类如3-羟基邻氨基苯甲酸、活性单酚类如2,6-二甲氧基苯酚和丁香醛连氮，以及发色团如ABTS。这是关于一种能够催化氧化迄今被认为是酪氨酸酶（L-酪氨酸）或漆酶（丁香醛连氮）特异性化合物的酶的首次报道，该酶具有甲酚酶、儿茶酚氧化酶和漆酶活性。这种PPO可能是研究非蓝铜和蓝铜氧化酶中铜位点的结构要求、催化机制及作用的非常有用的模型。
