title: Enzyme, protein, carbohydrate, and phenolic contaminants in commercial tyrosinase preparations: potential problems affecting tyrosinase activity and inhibition studies.
abstract: Commercial mushroom tyrosinase contains other proteins, enzymes, carbohydrates, and phenolic material besides tyrosinase. Carbohydrate and phenolic material comprise a large percentage of the powder resuspensions derived from Agaricus bisporus. Enzyme assays identified the presence of tyrosinase, laccase, beta-glucosidase, beta-galactosidase, beta-xylosidase, cellulase, chitinase, xylanase, and mannanase in the commercial tyrosinase. Protein sequencing indicated the presence of tyrosinase, a lectin, and a putative mannanase as well as 10 unidentified protein/peptides in the commercial tyrosinase preparations. Characteristics of tyrosinase isoforms were similar in two different commercial tyrosinase sources. Inhibition studies indicated that I 50 values for some tyrosinase inhibitors were different when the crude powder was compared to a partially purified tyrosinase. The presence of these contaminants has the potential to affect studies using commercial tyrosinase.
authors.affiliation: Department of Chemistry, Indiana State University, Terre Haute, Indiana 47809, USA. wflurkeyiii@isugw.indstate.edu
authors.forename: Allison
authors.initials: A
authors.lastname: Flurkey
authors.forename: Jena
authors.initials: J
authors.lastname: Cooksey
authors.forename: Akhila
authors.initials: A
authors.lastname: Reddy
authors.forename: Kelli
authors.initials: K
authors.lastname: Spoonmore
authors.forename: Antonio
authors.initials: A
authors.lastname: Rescigno
authors.forename: Jennifer
authors.initials: J
authors.lastname: Inlow
authors.forename: William H
authors.initials: WH
authors.lastname: Flurkey
mesh_terms: D000364:Agaricus / Q000201:enzymology*; D002241:Carbohydrates / Q000032:analysis*; D004340:Drug Contamination; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004798:Enzymes / Q000032:analysis; D014442:Monophenol Monooxygenase / Q000737:chemistry* / Q000378:metabolism; D010636:Phenols / Q000032:analysis*; D011506:Proteins / Q000032:analysis* / Q000737:chemistry
chemical_list: D002241:Carbohydrates; D004791:Enzyme Inhibitors; D004798:Enzymes; D010636:Phenols; D011506:Proteins; D014442:Monophenol Monooxygenase