title: Characterization of beta-glucosidase from a strain of Penicillium purpurogenum KJS506.
abstract: A novel beta-glucosidase (BGL)-producing strain was isolated and identified as Penicillium purpurogenum KJS506 based on its morphology and internal transcribed spacer (ITS) rDNA gene sequence. When rice straw and corn steep powder were used as carbon and nitrogen sources, respectively, the maximal BGL activity of 12.3 U ml(-1), one of the highest levels among BGL-producing microorganisms was observed. The optimum temperature and pH for BGL production were 32 degrees C and 4, respectively. An extracellular BGL was purified to homogeneity by sequential chromatography of P. purpurogenum culture supernatants, and the purified BGL showed higher activity (V (max) = 934 U mg protein(-1)) than most BGLs from other sources. The complete ORF of bgl3 was cloned from P. purpurogenum by a modified thermal asymmetric interlaced polymerase chain reaction. The bgl3 gene consists of a 2,571-bp ORF and encodes a putative protein containing 856 amino acids with a calculated molecular mass of 89,624 Da. The putative gene product was identified as a member of glycoside hydrolase family 3. The present results should contribute to improved industrial production of BGL by P. purpurogenum KJS506.
authors.affiliation: Department of Chemical Engineering, Konkuk University, Seoul, 143-701, South Korea.
authors.forename: Marimuthu
authors.initials: M
authors.lastname: Jeya
authors.forename: Ah-Reum
authors.initials: AR
authors.lastname: Joo
authors.forename: Kyoung-Mi
authors.initials: KM
authors.lastname: Lee
authors.forename: Manish Kumar
authors.initials: MK
authors.lastname: Tiwari
authors.forename: Kyoung-Min
authors.initials: KM
authors.lastname: Lee
authors.forename: Sang-Hwan
authors.initials: SH
authors.lastname: Kim
authors.forename: Jung-Kul
authors.initials: JK
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002244:Carbon / Q000378:metabolism; D003001:Cloning, Molecular; D004271:DNA, Fungal; D004274:DNA, Recombinant; D005285:Fermentation; D008958:Models, Molecular; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009584:Nitrogen / Q000378:metabolism; D010407:Penicillium / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D013379:Substrate Specificity; D013696:Temperature; D001617:beta-Glucosidase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D004271:DNA, Fungal; D004274:DNA, Recombinant; D002244:Carbon; D001617:beta-Glucosidase; D009584:Nitrogen