Zarivi Osvaldo, Bonfigli Antonella, Cesare Patrizia, Amicarelli Fernanda, Pacioni Giovanni, Miranda Michele
Department of Basic and Applied Biology, Faculty of Sciences, University of L'Aquila, Via Vetoio, I-67010 Coppito, L'Aquila, Italy.
FEMS Microbiol Lett. 2003 Mar 14;220(1):81-8. doi: 10.1016/S0378-1097(03)00065-X.
Tyrosinase is an enzyme having two copper atoms at the reactive site occurring in prokaryotic and eukaryotic organisms. In animals tyrosinase is responsible for pigmentation, in plants for protection of injured tissues or, as in fungi, to harden cell walls. Some of us have previously shown that tyrosinase is involved in truffle development and differentiation. Here we present the purification, the molecular properties and the reversible inhibition of Tuber melanosporum tyrosinase by dimethyl-sulfide and bis[methylthio]methane, the main flavour compounds of black and whitish truffles. The MW(r) is 39000. L-3,4-dihydroxyphenylalanine and L-tyrosine stain corresponding bands as expected for a true tyrosinase. Phenylthiourea, diethyldithiocarbamate and mimosine inhibit L-tyrosine and L-3,4-dihydroxyphenylalanine oxidation.
酪氨酸酶是一种在原核生物和真核生物的活性位点含有两个铜原子的酶。在动物体内，酪氨酸酶负责色素沉着；在植物中，它用于保护受伤组织；而在真菌中，它则用于硬化细胞壁。我们中的一些人之前已经表明酪氨酸酶参与松露的发育和分化。在此，我们展示了黑孢块菌酪氨酸酶的纯化、分子特性以及二甲基硫醚和双[甲硫基]甲烷（黑松露和白松露的主要风味化合物）对其的可逆抑制作用。其相对分子质量为39000。L - 3,4 - 二羟基苯丙氨酸和L - 酪氨酸能使相应条带显色，这正如真正的酪氨酸酶所预期的那样。苯基硫脲、二乙基二硫代氨基甲酸盐和含羞草碱可抑制L - 酪氨酸和L - 3,4 - 二羟基苯丙氨酸的氧化。
