title: Detection and characterization of a novel extracellular fungal enzyme that catalyzes the specific and hydrolytic cleavage of lignin guaiacylglycerol beta-aryl ether linkages.
abstract: Cleavage of the arylglycerol beta-aryl ether linkage is the most important process in the biological degradation of lignin. The bacterial beta-etherase was described previously and shown to be tightly associated with the cellular membrane. In this study, we aimed to detect and isolate a new extracellular function that catalyses the beta-aryl ether linkage cleavage of high-molecular lignin in the soil fungi. We screened and isolated 2BW-1 cells by using a highly sensitive fluorescence assay system. The beta-aryl ether cleavage enzyme was produced by a newly isolated fungus, 2BW-1, and is secreted into the extracellular fraction. The beta-aryl ether cleavage enzyme converts the guaiacylglycerol beta-O-guaiacyl ether (GOG) to guaiacylglycerol and guaiacol. It requires the C alpha alcohol structure and p-hydroxyl group and specifically attacks the beta-aryl ether linkage of high-molecular mass lignins with addition of two water molecules at the C alpha and C beta positions.
authors.affiliation: Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan. y-otuka@cc.tuat.ac.jp
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Otsuka
authors.forename: Tomonori
authors.initials: T
authors.lastname: Sonoki
authors.forename: Seiichiro
authors.initials: S
authors.lastname: Ikeda
authors.forename: Shinya
authors.initials: S
authors.lastname: Kajita
authors.forename: Masaya
authors.initials: M
authors.lastname: Nakamura
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Katayama
mesh_terms: D002384:Catalysis; D016923:Cell Death; D002462:Cell Membrane / Q000378:metabolism; D002965:Classification; D004275:DNA, Ribosomal / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005658:Fungi / Q000201:enzymology*; D006140:Guaifenesin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism*; D006868:Hydrolysis; D006923:Hymecromone / Q000378:metabolism; D007202:Indicators and Reagents / Q000494:pharmacology; D008031:Lignin / Q000378:metabolism*; D013058:Mass Spectrometry; D008856:Microscopy, Fluorescence; D008956:Models, Chemical; D010802:Phylogeny; D013379:Substrate Specificity; D013997:Time Factors
chemical_list: D004275:DNA, Ribosomal; D007202:Indicators and Reagents; D006923:Hymecromone; D006140:Guaifenesin; C046052:guaiacylglycerol-beta-guaiacyl ether; D008031:Lignin