Purification and properties of β-1,3-glucanase from Arthrobacter sp NHB-10 -: Note

A beta-1,3-glucanase [EC 3.2.1.39] was purified from the culture filtrate of arthrobacter sp. NHB-10, which lyses the cell wall of Aspergillus nip-er and Aspergillus japonicus, by column chromatographies on DEAE-Sepharose, Superose 12, and Mono Q. The enzyme preparation showed a single band with a molecular mass of about 73,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and with an isoelectric point of 3.0 on thin-layer agarose gel in electrofocusing. The purified enzyme specifically hydrolyzed laminarin and its oligosaccharides (laminaritriose to laminariheptaose) by an endo-type action, but not laminaribiose and lichenan. The optimum pH and temperature for the enzyme activity were 6.5 and 50 degrees C. The enzyme was stable in a pH range from 4.0 to 11.0 and up to 45 degrees C. The N-terminal amino acid sequence of the purified enzyme was determined to be EPAPDPDLGPNVVFIDD.