The Multiple Forms of Mushroom Tyrosinase

The Multiple Forms of Mushroom Tyrosinase

The four isozymes of mushroom tyrosinase can be partially resolved by analytical electrophoresis on acrylamide gel. Three of the four have similar sedimentation coefficients around 7.2 S, while that of or-tyrosinase is 6.7 S. The molecular weight of /34yrosinase, calculated from sedhnentation velocity and diiIusion data, is 123,800, in good agreement with other published values for mushroom tyr...

The multiple forms of mushroom tyrosinase. Purification and molecular properties of the enzymes.

We have undertaken the purification of mushroom tyrosinase to obtain homogeneous enzyme for a study of its mechanism, which is unknown. Purified mushroom tyrosinases have already been reported (l-9). Some of these preparations were homogeneous, or almost homogeneous, by either electrophoresis or ultracentrifugation; one was homogeneous by both criteria (3, 9). However, there are discrepancies a...

The inhibition effects of melon on mushroom tyrosinase activity

The  inhibition effects seed and peel of melon on diphenolase activity of mashroom tyrosinase were investigated. The IC50 values and Ki values of seed and peel of melon were evaluated. increased the Km value and decreased the Vm value so it show mixed type inhibition on mushroom tyrosinase when L-DOPA was used as a substrate.

Purification of Tyrosinase from Edible Mushroom

Peroxidase, "protyrosinase," and the multiple forms of tyrosinase in mice.

Mammalian tyrosinase as currently defined has two catalytic functions: 1) the oxidation of tyrosine to L-3,4-dihydroxyphenylalanine (dopa) and 2) the oxidation of dopa to dopa quinone (1-9). Although an imposing body of evidence has been advanced in support of this interpretation, Okun and associates have recently challenged the prevailing concept of the action of tyrosinase ( 10, 11 ). They ha...