By Ryan Meek

Faculty Mentor: Dr. Randall Reif, Ph.D.

Abstract

Tyrosinase is the chief active agent in the production of melanin and in the browning of fruits and vegetables. The reaction it catalyzes produces a pigmented product whose production can be easily measured in a spectrophotometer. For this reason, the Biochemistry I Lab at the University of Mary Washington conducts a multi-week project utilizing tyrosinase to study enzyme kinetics. This study sought to contribute to the biochemistry lab by identifying new types of inhibitors for tyrosinase to allow students to experimentally determine different types of inhibitors. This was done by running a series of enzyme assays with two different inhibitors, benzyl alcohol and cyanide, and performing Lineweaver-Burke analysis to determine Vmax and Km. The studies showed both benzyl alcohol and cyanide to be competitive inhibitors with Vmax’s of 0.1145 – 0.246 µmol/sec and 0.0548 – 0.1012 µmol/sec respectively. The Km values for benzyl alcohol and cyanide were determined to be 0.2818 M (uninhibited), 1.6947 M (50% activity), and 11.1973 M (10% activity), and 0.5039 M (uninhibited), 0.4183 M (50% activity), and 3.5259 M (10% activity) respectively. This data did not identify any new types of inhibitors that were not already available for the biochemistry lab but expanded the options of inhibitors available to the students.