title: Purification and characterization of an extracellular beta-glucosidase produced by Phoma sp. KCTC11825BP isolated from rotten mandarin peel.
abstract: A beta-glucosidase from Phoma sp. KCTC11825BP isolated from rotten mandarin peel was purified 8.5-fold with a specific activity of 84.5 U/mg protein. The purified enzyme had a molecular mass of 440 kDa with a subunit of 110 kDa. The partial amino acid sequence of the purified beta-glucosidase evidenced high homology with the fungal beta- glucosidases belonging to glycosyl hydrolase family 3. Its optimal activity was detected at pH 4.5 and 60 degrees C, and the enzyme had a half-life of 53 h at 60 degrees C. The Km values for p-nitrophenyl-beta-D-glucopyranoside and cellobiose were 0.3 mM and 3.2 mM, respectively. The enzyme was competitively inhibited by both glucose (Ki=1.7 mM) and glucono-delta-lactone (Ki=0.1 mM) when pNPG was used as the substrate. Its activity was inhibited by 41% by 10 mM Cu2+ and stimulated by 20% by 10 mM Mg2+.
authors: Eco Technology Center, Chungcheong Regional Division, Korea Institute of Industrial Technology, Cheonan, Chungnam, Republic of Korea.
authors: Jung-Youn
authors: JY
authors: Choi
authors: Ah-Reum
authors: AR
authors: Park
authors: Yong Jin
authors: YJ
authors: Kim
authors: Jae-Jin
authors: JJ
authors: Kim
authors: Chang-Jun
authors: CJ
authors: Cha
authors: Jeong-Jun
authors: JJ
authors: Yoon