title: Purification and characterization of a carbohydrate: acceptor oxidoreductase from Paraconiothyrium sp. that produces lactobionic acid efficiently.
abstract: A carbohydrate:acceptor oxidoreductase from Paraconiothyrium sp. was purified and characterized. The enzyme efficiently oxidized beta-(1-->4) linked sugars, such as lactose, xylobiose, and cellooligosaccharides. The enzyme also oxidized maltooligosaccharides, D-glucose, D-xylose, D-galactose, L-arabinose, and 6-deoxy-D-glucose. It specifically oxidized the beta-anomer of lactose. Molecular oxygen and 2,6-dichlorophenol indophenol were reduced by the enzyme as electron acceptors. The Paraconiothyrium enzyme was identified as a carbohydrate:acceptor oxidoreductase according to its specificity for electron donors and acceptors, and its molecular properties, as well as the N-terminal amino acid sequence. Further comparison of the amino acid sequences of lactose oxidizing enzymes indicated that carbohydrate:acceptor oxidoreductases belong to the same group as glucooligosaccharide oxidase, while they differ from cellobiose dehydrogenases and cellobiose:quinone oxidoreductases.
authors.affiliation: Osaka Municipal Technical Research Institute, 6-50 Morinomiya 1-chome, Osaka 536-8553, Japan. kiryu@omtri.city.osaka.jp
authors.forename: Takaaki
authors.initials: T
authors.lastname: Kiryu
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Nakano
authors.forename: Taro
authors.initials: T
authors.lastname: Kiso
authors.forename: Hiromi
authors.initials: H
authors.lastname: Murakami
mesh_terms: D000429:Alcohol Oxidoreductases; D002237:Carbohydrate Dehydrogenases / Q000302:isolation & purification* / Q000378:metabolism*; D004187:Disaccharides / Q000096:biosynthesis*; D004795:Enzyme Stability; D005656:Fungal Proteins / Q000302:isolation & purification* / Q000378:metabolism; D007785:Lactose / Q000378:metabolism*
chemical_list: D004187:Disaccharides; D005656:Fungal Proteins; C005608:lactobionic acid; D000429:Alcohol Oxidoreductases; D002237:Carbohydrate Dehydrogenases; C072250:glucooligosaccharide oxidase; D007785:Lactose