Faculty of Biotechnology and Food Sciences in Nitra Journal of Microbiology, Biotechnology and Food Sciences 1338-5178 vol. 5 2016 2016-04-01 2016-04-01 CHARACTERIZATION OF TYROSINASE ENZYME FROM NATIVE BACILLUS MEGATERIUM SP. STRAIN M36 465 469 EN Ebrahim Valipour Ebrahim Valipour Burhan Arikan Burhan Arikan Tyrosinase is a type 3 copper-containing enzyme that catalyzes the conversion of l-tyrosine to L-DOPA and finally to melanin. In this study tyrosinase enzyme from native Bacillus megaterium sp. strain M36, was produces, characterized and used to produce L-DOPA. The M36 tyrosinase enzyme showed optimum monophenolase and diphenolase activity at pH 7.5 and conserved its maximum activity over than 95 % at pH ranging from 6.5 to 8.0. The M36 tyrosinase enzyme showed optimum monophenolase and diphenolase activity at 40 °C also, the enzyme conserved 100% of its original activity at 4-45 °C. The M36 tyrosinase enzyme was inhibited strongly by β-mercaptoethanol and about 90% by 5mmol of EDTA (a chelating agent). Although the enzyme was activated at the presence of 1mM SDS, it was strongly inhibited at high concentration of SDS (above 15mM). In TLC analysis, the transformation of L-tyrosine to L-DOPA was conspicuously detected.