D-l,3-Glucanases

Glucoamylases.—Although the molecular weight and the carbohydrate content of Aspergillus awamori glucoamylase were reduced on treatment with subtilisin, most of the enzymic activity was retained. The modified enzyme was less stable and its ability to hydrolyse starch was diminished. 

Reduction and carboxymethylation of A. niger glucoamylase resulted in complete loss of enzymic activity, whereas O-acetylation of three of the 13 tyrosyl residues resulted in loss of 20% of the enzymic activity. The tryptophanyl residues of Rhizopus niveus glucoamylase have been modified by treatment with A-bromosuccinimide so that the subsite structure of the enzyme could be studied.  

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