Abstract
The activating factors of the inactive protease in cell-free extracts obtained from growing mycelia of Aspergillus sojae KS were studied. It was found that the several kinds of metals were involved in activation, and the role of these metals on the activation was investigated. The velocity of the activation was maximal around pH 10 as well as around pH 5. It was proved that a kinase (enzyme) capable of activating the inactive protease in alkaline solution does exist in the cell-free extract.