Purification and characterization of thermostable α-galactosidase from Ganoderma lucidum

• Main Authors: Sripuan T., Aoki K., Yamamoto K., Tongkao D., Kumagai H.
• Format: Article
• Language: English
• Published: 2014
• Online Access: http://www.scopus.com/inward/record.url?eid=2-s2.0-2442419823&partnerID=40&md5=2d81fd7bbae1df8033661e67f49e9282; http://cmuir.cmu.ac.th/handle/6653943832/6040
• Institution: Chiang Mai University

α-Galactosidase was purified from a fresh fruiting body of Ganoderma lucidum by precipitation with ammonium sulfate and column chromatographies with DEAE-Sephadex and Con A-Sepharose. The purified enzyme was homogeneous on polyacrylamide gel electrophoresis. Its N-terminal amino acid sequence was similar to that of Mortierella vinacea α-galactosidase. The molecular mass of the enzyme was about 56 kDa by SDS-polyacrylamide gel electrophoresis, and about 249 kDa by gel filtration column chromatography. The optimum pH and temperature were 6.0 and 70°C, respectively. The enzyme was fully stable to heating at 70°C for 30 min. It hydrolyzed p-nitrophenyl-α-D- galactopyranoside (Km = 0.4 mM) but hydrolyzed little o-nitrophenyl-α-D-galactopyranoside. It also hydrolyzed melibiose, raffinose, and stachyose. The enzyme catalyzed the transgalactosylation reaction which synthesized melibiose. The product was confirmed by various analyses.