title: Transcription analysis of pyranose dehydrogenase from the basidiomycete Agaricus bisporus and characterization of the recombinantly expressed enzyme.
abstract: Agaricus bisporus is a litter degrading basidiomycete commonly found in humic-rich environments. It is used as model organism and cultivated in large scale for food industry. Due to its ecological niche it produces a variety of enzymes for detoxification and degradation of humified plant litter. One of these, pyranose dehydrogenase, is thought to play a role in detoxification and lignocellulose degradation. It is a member of the glucose-methanol-choline family of flavin-dependent enzymes and oxidizes a wide range of sugars with concomitant reduction of electron acceptors like quinones. In this work, transcription of pdh in A. bisporus was investigated with real-time PCR revealing influence of the carbon source on pdh expression levels. The gene was isolated and heterologously expressed in Pichia pastoris. Characterization of the recombinant enzyme showed a higher affinity towards disaccharides compared to other tested pyranose dehydrogenases from related Agariceae. Homology modeling and sequence alignments indicated that two loops of high sequence variability at substrate access site could play an important role in modulating these substrate specificities.
authors.affiliation: Food Biotechnology Laboratory, Department of Food Sciences and Technology, University of Natural Resources and Life Sciences, Vienna, Austria.
authors.forename: Christoph
authors.initials: C
authors.lastname: Gonaus
authors.affiliation: Food Biotechnology Laboratory, Department of Food Sciences and Technology, University of Natural Resources and Life Sciences, Vienna, Austria.
authors.forename: Roman
authors.initials: R
authors.lastname: Kittl
authors.affiliation: Food Biotechnology Laboratory, Department of Food Sciences and Technology, University of Natural Resources and Life Sciences, Vienna, Austria.
authors.forename: Christoph
authors.initials: C
authors.lastname: Sygmund
authors.affiliation: Food Biotechnology Laboratory, Department of Food Sciences and Technology, University of Natural Resources and Life Sciences, Vienna, Austria.
authors.forename: Dietmar
authors.initials: D
authors.lastname: Haltrich
authors.affiliation: Food Biotechnology Laboratory, Department of Food Sciences and Technology, University of Natural Resources and Life Sciences, Vienna, Austria. Electronic address: clemens.peterbauer@boku.ac.at.
authors.forename: Clemens
authors.initials: C
authors.lastname: Peterbauer
mesh_terms: D000364:Agaricus / Q000201:enzymology*; D000595:Amino Acid Sequence; D002237:Carbohydrate Dehydrogenases / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D020134:Catalytic Domain; D005656:Fungal Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D040681:Structural Homology, Protein; D013379:Substrate Specificity; D014158:Transcription, Genetic
chemical_list: D005656:Fungal Proteins; D011994:Recombinant Proteins; D002237:Carbohydrate Dehydrogenases
keywords: Agaricus bisporus; Oxidoreductase; Pyranose dehydrogenase