title: Purification and properties of an α-(1 → 3)-glucanase (EC 3.2.1.84) from Trichoderma harzianum and its use for reduction of artificial dental plaque accumulation.
abstract: Extracellular α-(1 → 3)-glucanase (mutanase, EC 3.2.1.84) produced by Trichoderma harzianum CCM F-340 was purified to homogeneity by ultrafiltration followed by ion exchange and hydrophobic interaction chromatography, and final chromatofocusing. The enzyme was recovered with an 18.4-fold increase in specific activity and a yield of 4.3%. Some properties of the α-(1 → 3)-glucanase were investigated. The molecular mass of the enzyme is 67 kDa, as estimated by SDS/PAGE, its isoelectric point 7.1, and the carbohydrate content 3%. The pH and temperature optima are 5.5 and 45°C, respectively. The enzyme is stable over a pH range of 4.5-6.0 and up to 45°C for 1 h. The Km and Vmax under standard assay conditions are 0.73 mg/ml and 11.39 x 10(-2) µmol/min/mg protein, respectively. The enzyme activity is stimulated by addition of Mg(2+) and Na(+), and significantly inhibited by Hg(2+). The α-(1 → 3)-glucanase preparation preferentially catalyzed the hydrolysis of various streptococcal mutans and fungal α-(1 → 3)-glucans. The 20-residue N-terminal sequence of the enzyme is identical with those of other α-(1 → 3)-glucanases from the genus Trichoderma, and highly similar to those from other fungi. The purified α-(1 → 3)-glucanase was effective in preventing artificial dental plaque formation. The easy purification from fermentation broth and high stability, and the effective inhibition of oral biofilm accumulation make this α-(1 → 3)-glucanase highly useful for industrial and medical application.
authors.affiliation: Department of Industrial Microbiology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Lublin, Poland. adrianw2@wp.pl
authors.forename: Adrian
authors.initials: A
authors.lastname: Wiater
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Pleszczyńska
authors.forename: Jerzy
authors.initials: J
authors.lastname: Rogalski
authors.forename: Lucyna
authors.initials: L
authors.lastname: Szajnecka
authors.forename: Janusz
authors.initials: J
authors.lastname: Szczodrak
mesh_terms: D000595:Amino Acid Sequence; D018441:Biofilms / Q000187:drug effects; D003773:Dental Plaque / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D005936:Glucans / Q000378:metabolism; D006026:Glycoside Hydrolases / Q000302:isolation & purification* / Q000378:metabolism* / Q000494:pharmacology; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D013379:Substrate Specificity; D014242:Trichoderma / Q000201:enzymology*
chemical_list: D005936:Glucans; D006026:Glycoside Hydrolases; C021780:exo-1,3-alpha-glucanase