title: Laccases of Pleurotus sapidus: characterization and cloning.
abstract: Peanut shells, a major waste stream of food processing, served as a renewable substrate for inducing the production of laccases by basidiomycetes. Of 46 surface cultures examined, 29 showed laccase activity under the experimental conditions. The edible fungus Pleurotus sapidus was selected as the most active producer, immobilized on the shells, and cultivated in the fed-batch mode. A continuous rise in laccase activity was found, indicating the inducibility of laccase secretion by the peanut shells and the reusability of the mycelium. Two laccase isoenzymes were purified by decoupled 2-D electrophoresis, and amino acid sequence information was obtained by electrospray ionization tandem mass spectrometry. cDNAs of the corresponding gene and another laccase were cloned and sequenced using a PCR-based screening of a synthesized P. sapidus cDNA library. Data bank searches against public databases returned laccases of P. ostreatus and P. sajor-caju as the best hits. The potential use of laccases by the food industry is discussed.
authors.affiliation: Zentrum Angewandte Chemie, Institut für Lebensmittelchemie der Universität Hannover, Wunstorfer Strasse 14, D-30453 Hannover, Germany.
authors.forename: Diana
authors.initials: D
authors.lastname: Linke
authors.forename: Henning
authors.initials: H
authors.lastname: Bouws
authors.forename: Thilo
authors.initials: T
authors.lastname: Peters
authors.forename: Manfred
authors.initials: M
authors.lastname: Nimtz
authors.forename: Ralf G
authors.initials: RG
authors.lastname: Berger
authors.forename: Holger
authors.initials: H
authors.lastname: Zorn
mesh_terms: D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D042845:Laccase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D015394:Molecular Structure; D020076:Pleurotus / Q000201:enzymology*; D016133:Polymerase Chain Reaction; D021241:Spectrometry, Mass, Electrospray Ionization; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D018076:DNA, Complementary; D007527:Isoenzymes; D042845:Laccase