title: Kinetic properties of manganese peroxidase from the mushroom Stereum ostrea and its ability to decolorize dyes.
abstract: Manganese peroxidase (MnP) was isolated from the culture filtrate of the wood log mushroom Stereum ostrea (S. ostrea), grown on Koroljova medium, and then purified by ammonium sulfate [70% (w/v)] fractionation, DEAE-cellulose anion exchange chromatography, and Sephadex G-100 column chromatography, with an attainment of 88.6-fold purification and the recovery of 22.8% of initial activity. According to SDS-PAGE the molecular mass of the MnP was 40 kDa. The optimal pH and temperature were found to be 4.5 and 35 degrees C, respectively. The enzyme was stable even after exposure to a pH range of 4.5 to 6.0, and at temperatures of up to 35 degrees C at a pH of 4.5 for 1h. The K(m) and V(max) values for the substrate phenol red were found to be 8 micronm and 111.14 U/mg of protein, respectively. The MnP also oxidized other substrates such as guaiacol, DMP, and veratryl alcohol. Sodium azide, EDTA, SDS, Cu(2+), and Fe(2+), at 1-5 mM, strongly inhibited enzyme activity, whereas Ca(2+) and Zn(2+) increased enzyme activity. The participation of the purified enzyme in the decolorization of dyes suggests that S. ostrea manganese peroxidase could be effectively employed in textile industries.
authors.affiliation: Department of Microbiology, Sri Krishnadevaraya University, Anantapur-515 055, Andhra Pradesh, India.
authors.forename: K
authors.initials: K
authors.lastname: Praveen
authors.forename: K Y
authors.initials: KY
authors.lastname: Usha
authors.forename: Buddolla
authors.initials: B
authors.lastname: Viswanath
authors.forename: B Rajasekhar
authors.initials: BR
authors.lastname: Reddy
mesh_terms: D000363:Agaricales / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D004396:Coloring Agents / Q000737:chemistry / Q000378:metabolism*; D004795:Enzyme Stability; D005656:Fungal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008970:Molecular Weight; D010544:Peroxidases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D013379:Substrate Specificity; D013696:Temperature; D014934:Wood / Q000382:microbiology
chemical_list: D004396:Coloring Agents; D005656:Fungal Proteins; D010544:Peroxidases; C051129:manganese peroxidase