Results
Title

Partial Purification and Characterization of a Novel Extracellular Tyrosinase from Auricularia auricula.

Authors

Zou, Yu; Hu, Wenzhong; Jiang, Aili; Ma, Kun

Abstract

Extracellular tyrosinase from Auricularia auricula RF201 was purified in a three-step procedure involving ammonium sulfate precipitation, Sephadex G-100, and DEAE-Sepharose column chromatography. The partially purified enzyme showed a single protein band of 12.6 kDa on SDS-PAGE. The optimum pH for tyrosinase activity was 7, and the enzyme was stable between pH 6 and 9. Tyrosinase has optimal activity at 40 °C and retained most of its activity between 4 and 50 °C. A. auricula tyrosinase could oxidize l-tyrosine, l-DOPA, catechol, and caffeic acid and displayed dark brown or peach color. However, the enzyme was unable to catalyze l-phenylalanine and ferulic acid. In comparison with other substrates, l-tyrosine displayed the highest affinity ( K of 0.11 mM) and the maximal reaction velocity ( V of 102.58 μmol/min). Tyrosinase activity was reduced in the presence of numerous tested compounds. Particularly SDS, it significantly inhibited enzyme activity. CuSO and NaCl showed an activation effect on enzyme activity, with the maximum activation found in the presence of CuSO.

Subjects

AURICULARIA auricula-judae; PHENOL oxidase; PRECIPITATION (Chemistry); COLUMN chromatography; POLYACRYLAMIDE gel electrophoresis; ENZYME regulation

Publication

Applied Biochemistry & Biotechnology, 2014, Vol 172, Issue 3, p1460

ISSN

0273-2289

Publication type

Academic Journal

DOI

10.1007/s12010-013-0638-8