title: Interference of laccase in determination of cellobiose dehydrogenase activity of Pleurotus ostreatus (Florida) using dichlorophenol indophenol as the electron acceptor.
abstract: Pleurotus ostreatus (Florida), ITCC 3308 produces approximately 9.0 U/ml extracellular cellobiose dehydrogenase (CDH) in cellulose medium after 7 days of growth. However, no activity could be detected if the assay was done with cellobiose as the substrate and 2,6-dichlorophenol indophenol (DPIP) as the electron acceptor in absence of any laccase inhibitor. Kinetic study showed that V(max)/K(m) value was very high for rDPIP (reduced 2,6-dichlrophenol indophenol) oxidation by laccase. Oxygen consumption rate of rDPIP oxidation by the enzyme was found to be highest among all the tested substrates. The present study indicated that rDPIP was a good substrate for laccase. Therefore, caution is needed to measure CDH activity by monitoring DPIP reduction in a system where laccase is likely to be present.
authors.affiliation: Indian Institute of Chemical Biology, 4 Raja SC Mullick Road, Calcutta 700 032, India.
authors.forename: Tanima
authors.initials: T
authors.lastname: Saha
authors.forename: Tapas Kumar
authors.initials: TK
authors.lastname: Chakraborty
authors.forename: Rina
authors.initials: R
authors.lastname: Saha
authors.forename: Nirmalendu
authors.initials: N
authors.lastname: Das
authors.forename: Mina
authors.initials: M
authors.lastname: Mukherjee
mesh_terms: D015086:2,6-Dichloroindophenol; D002237:Carbohydrate Dehydrogenases / Q000032:analysis* / Q000378:metabolism; D002482:Cellulose; D003470:Culture Media; D007700:Kinetics; D042845:Laccase / Q000032:analysis / Q000037:antagonists & inhibitors / Q000378:metabolism; D020076:Pleurotus / Q000254:growth & development / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D003470:Culture Media; D002482:Cellulose; D015086:2,6-Dichloroindophenol; D002237:Carbohydrate Dehydrogenases; C019859:cellobiose-quinone oxidoreductase; D042845:Laccase