Purification and properties of Neurospora crassa laccase.
Extracellular Neurospora laccase (p-diphenol:oxygen oxidoreductase; EC 1.10.3.2) has been purified to apparent homogeneity by classical purification techniques. The enzyme, which consists of mainly one form, has a molecular weight of 64,800 and contains 11% carbohydrate. The ultraviolet, visible, and electron paramagnetic resonance spectra indicate that both type I and type II copper are present, as described for the Polyporus versicolor enzyme. With the exception of phloroglucinol, only para- and ortho-diphenols serve as effective substrates for the enzyme. Like the extracellular form, intracellular laccase is a glycoprotein as shown by its ability to bind to Concanavalin A Sepharose. Other studies, including gel filtration and ion-exchange chromatography, revealed no differences between the intracellular and extracellular enzymes, suggesting that intracellular laccase is destined for excretion by the cell.
D000596:Amino Acids / Q000032:analysis; D000645:Ammonium Sulfate; D002241:Carbohydrates / Q000032:analysis; D004156:Catechol Oxidase / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism; D011232:Chemical Precipitation; D002845:Chromatography; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D003300:Copper / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel; D006023:Glycoproteins / Q000032:analysis; D006882:Hydroxyapatites; D008970:Molecular Weight; D009491:Neurospora / Q000201:enzymology*; D009492:Neurospora crassa / Q000201:enzymology*; D010636:Phenols / Q000378:metabolism; D013056:Spectrophotometry, Ultraviolet; D014462:Ultrafiltration
D000596:Amino Acids; D002241:Carbohydrates; D006023:Glycoproteins; D006882:Hydroxyapatites; D010636:Phenols; D003300:Copper; D004156:Catechol Oxidase; D000645:Ammonium Sulfate