Crystallization and preliminary X-ray crystallographic analysis of tyrosinase from the mushroom Agaricus bisporus

Tyrosinase catalyzes the conversion of tyrosine to dihydroxyphenylalanine quinone, which is the main precursor for the biosynthesis of melanin. The enzyme from Agaricus bisporus, the common button mushroom, was purified and crystallized in two different space groups. Crystals belonging to space group P2₁ (unit-cell parameters a = 104.2, b = 105.0, c = 119.1 Å, β = 110.6°, four molecules per asymmetric unit) diffracted to 3.0 Å resolution. Crystals belonging to space group P2₁2₁2 (unit-cell parameters a = 104.0, b = 104.5, c = 108.4 Å, two molecules per asymmetric unit) diffracted to 2.6 Å resolution. It was essential to include 5 mM HoCl₃ in all crystallization conditions in order to obtain well diffracting crystals.