Conidia of aspergillus oryzae as naturally immobilized phosphatases

• Published in: Agricultural and biological chemistry Vol. 44; no. 12; pp. 2825 - 2829
• Main Authors: Kuninaka, Akira, Rokugawa, Kyuji, Yoshino, Hiroshi
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 1980
• Subjects: Aspergillus oryzae
• ISSN: 0002-1369
• DOI: 10.1080/00021369.1980.10864420

The following enzymes were detected in conidia of Aspergillus oryzae var. No. 13 that were collected from a soy sauce factory: phosphatases acting nonspecifically on nucleotides; ribosidase(s) acting on adenosine, inosine, guanosine and xanthosine; and deaminases acting on guanine, adenosine, guanosine, cytidine, AMP and GMP. Most phosphatase activity was found to be bound firmly to the conidia. Thus, when a nucleotide solution was passed through a conidia-containing column, the corresponding nucleoside was recovered as a clear and colorless solution. The bound phosphatases were rather stable at pH 4 to 9 and at temperatures below 50°C. The optimum conditions for activity were at about 45°C and at pH about 5 and 8. When UMP·Na 2 solution was passed through a column containing 5 g of the conidia, about 200 mg of substrate was hydrolyzed per 1 hr. Conidia of molds belonging to the genus Aspergillus may be industrially employed as naturally immobilized phosphatases.