Chitin synthase zymogen

Chi tin synthase/chitin synthase zymogen (D 1.4.1) M Plasma membrane ... 

From fungi, so-called chitosomes, i.e., 105 S particles with a microvesicle-like morphology, were isolated which contain chitin synthase zymogen. 

The reaction is catalyzed by a single enzyme, namely, UDP-2-acetamido-2-deoxy-D-glucose chitin 2-acetamido-2-deoxy-D-glucosyltransferase (chitin synthase, EC 2.4.1.16). Particulate preparations of chitin synthase obtained from different fungi211 did not show significant differences. The enzyme exists in the cells as inactive zymogen, and can be converted into the active form by limited proteolysis.212 The zymogenic character of chitin synthase was also confirmed in solubilized preparations,213,214 as well as in preparations from other sources.211... 

Plasma membranes from Schizophyllum commune protoplasts have been stabilized against fragmentation by coating the protoplasts with concanavalin Approximately half of the chitin synthase activity is associated with the plasma membranes in the form of a zymogen and could not be detached from the membranes. It is suggested that this inactive form represents the cytoplasmic transport form of the enzyme. The nature and location of proteases of Aspergillus nidulans and the interaction of one of these with the zymogen of chitin synthetase have been described. ... 

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