EXPRESSION AND CHARACTERIZATION OF RECOMBINANT β-GLUCOSIDASES FROM ASPERGILLUS NIDULANS AN2227

Authors

  • R. Auta Department of Biochemistry, Kaduna State University, Tafawa Balewa Way, Kaduna
  • A.D. Wusu Cellular, Molecular and Environmental Unit. Department of Biochemistry, Faculty of Science, Lagos State University, Ojo, Lagos Nigeria.
  • I. Radecka Department of Biology, Chemistry and Forensic Science, School of Science and Engineering, University of Wolverhampton, WV1 1LY, United Kingdom.
  • P. Hooley Department of Biology, Chemistry and Forensic Science, School of Science and Engineering, University of Wolverhampton, WV1 1LY, United Kingdom.

Abstract

Recombinant β-glucosidase (EC 3.2.1.21) from Aspergillus nidulans AN2227 was expressed using Buffered Methanol Complex Medium (BMMY). Purification was conducted using ammonium sulphate precipitation and anion exchange chromatography on DEAE-Sephadex A-50 column. The enzyme was purified 2.58 fold from the crude extract. β-glucosidase was purified to electrophoretic homogeneity and had a relative molecular weight of 100 kDa as determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme had an optimum pH and temperature of 6.0 and 40 oC respectively. The most striking characteristics of this enzyme are the dramatically broad pH and temperature profile. The enzyme also had a Km of 0.42 mM for 4-Nitrophenyl-β-D-glucopyranoside (pNPG). The activity of the enzyme was inhibited by HgCl2 and slightly activated by CoCl2, FeCl3, CaCl2, FeCl2 and ZnCl2 suggesting that the enzyme may not be a metalloprotein and therefore does not require metal ions for optimum activity.  

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Published

2016-07-24

Issue

Vol. 11 No. 2 (2016)

Section

ARTICLES