abstract |
A mutant strain of Aspergillus oryzae that has few accompanying mutations and could not be obtained by a conventional mutation method, for example, has a ability to produce a protease of 1,100 U / g 、 or more and produces a glutaminase of 2.0 U / g 麹 or more. Aspergillus oryzae having the ability and a gene deletion mutant (pyrG mutant) are obtained. SOLUTION: Aspergillus soya and the same oryzae are irradiated with a heavy ion beam, and the desired microbiological features are obtained by selecting the mutant jaundice from the irradiated body and its culture. A mutant strain of jaundice is obtained. [Selection figure] None |