Purification and characterization of a B-glucosidase from the phytopathogenic fungus Fusarium oxysporum f.sp. melonis

ALCONADA TERESA; MARTÍNEZ, MARÍA JESÚS

LETTERS IN APPLIED MICROBIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 1996 vol. 22 p. 106 - 110

0266-8254

1996. Fusarium oxysporum f. sp. melonas produces cellulase and P-glucosidase activities in a medium with glucose and avicel as carbon source. A P-glucosidase from this crude material was purified by gel filtration and ion exchange chromatography successively. This enzyme is a unique band of protein in SDSPAGE and isoelectric focussing. It had a molecular weight of 66 000 and a PI of 5. Using p-nitrophenyl-P-D-glucopyranoside as substrate P-glucosidase shows a K, of 210 pmol 1-I, an optimum pH of 5.5 and an optimum reaction temperature of 60°C, being stable in a pH range of 5-7 for 48 h at room temperature.