title: Some Properties of Extracellular Acetylxylan Esterase Produced by the Yeast Rhodotorula mucilaginosa.
abstract: The red yeast Rhodotorula mucilaginosa produced an esterase that accumulated in the culture supernatant on induction with triacetin. The enzyme was specific for substrates bearing an O-acetyl group, but was relatively nonspecific for the rest of the molecule, which could consist of a phenol, a monosaccharide, a polysaccharide, or an aliphatic alcohol. The esterase was more active against acetylxylan and glucose beta-d-pentaacetate than were a number of esterases from plant and animal sources, when activities on 4-nitrophenyl acetate were compared. The enzyme exhibited Michaelis-Menten kinetics and was active over a broad pH range (5.5 to 9.2), with an optimum between pH 8 and 10. In addition, the enzyme retained its activity for 2 h at 55 degrees C. The yeast that produced the enzyme did not produce xylanase and, hence, is of interest for the production of acetylxylan esterase that is free of xylanolytic activity.
authors.affiliation: Division of Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada K1A OR6.
authors.forename: H
authors.initials: H
authors.lastname: Lee
authors.forename: R J
authors.initials: RJ
authors.lastname: To
authors.forename: R K
authors.initials: RK
authors.lastname: Latta
authors.forename: P
authors.initials: P
authors.lastname: Biely
authors.forename: H
authors.initials: H
authors.lastname: Schneider