ELECTROPHORETIC PATTERN OF HUMAN HAIRBULB TYROSINASE

[摘要] A small gel electrophoresis system was developed for the study of tyrosinase from human hairbulb melanocytes. Enzyme is released from the hairbulb with Triton X-100. Electrophoresis is run in 60 mm microcapillary pipettes with an internal diameter of 1.5 mm. With this technique, tyrosinase from normally pigmented brown, black, blond and red hairbulbs gave a single band when the gel was stained with L-dopa for enzyme activity. Tyrosinase from tyrosinase-positive oculocutaneous albino and Hermansky-Pudlak syndrome hairbulbs gave a single L-dopa band. Neuraminidase pretreatment of the tyrosinase from normal and albino hairbulbs changed the migration of the tyrosinase band to a less anodal position. Trypsin pretreatment had no effect. Human hairbulb tyrosinase is a glycoprotein. Tyrosinase-positive albino tyrosinase has no major electrophoretic difference from normal enzyme.