Abstract
The biosyntheses of the main components of mycelial cell walls on Cochliobolus miyabeanus (β-glucan, β-1, 3-linked glucan having branched units connected through C-6 and C-1 ; chitin-like substance, β-1, 4-linked N-acetylglucosamine having branched units of N-acetylgalactosamine connected through C-1 by α-glycosidic linkage) were studied. The incorporation of 14C-glucose or 14C-N-acetylglucosamine from uridine diphosphate (UDP)-derivative into β-glucan or chitin-like substance was catalyzed by the particulate enzymes obtained from mycelia. The optimum conditions of these synthetic reaction were as follows : for glucan ; 0.08M Tris-HCl buffer pH 8.2 (contained 0.01M MgCl2 and 0.001M ethylenediamine tetraacetic acid (EDTA)), cell wall glucan, 0.08M UDP-14C-glucose (5 μCi/ml) and enzyme solution ; for chitin-like substance ; 0.08M Tris-HCl buffer pH 7.5 (contained 0.01M MgCl2 and 0.001M EDTA), cell wall chitodextrin, 0.08M UDP-14C-N-acetylglucosamine (5 μCi/ml) and enzyme solution.