In the course of a study on glutaminase of koji mold, we found that the enzyme purified from koji mold, Aspergillus oryzae MA-27-IM, could catalyze the y-glutamyltranspeptidation (GGT) reaction.!) This was the first reported case of a filamentous fungus, though GGT reactions in animals and bacteria have been reported2-S) In this reaction, the y-glutamyl moiety of Ly- glutamyl-p-nitroanilide was transferred to a peptide, glycylglycine, to yield y- ...