[Modification of the carboxyl and amine groups of the cellulolytic enzymes of Aspergillus awamori].
The activity and stability of some enzymes of Asp. awamori cellulolytic complex were studied as affected by chemical modification of carboxylic groups with N,N'-dicyclohexyl carbodiimide (DCCD) and amine groups with glutaric aldehyde. The carboxylic groups are established to be necessary for manifestation of the activities of C1- and C2-cellulases, Cx-exo- and Cx-endoglucanases. Their role is negligible in the action of beta-glucosidase. The activity of individual cellulases was studied as affected by nucleophilic substitution of DCCD-activated COOH-groups by various reagents (glycine amide, leucine amide, tyrosine amide and N-benzoyl-l-arginine-methyl ether-hydrochloride). Tyrosine amide is the least inacting reagent for all the enzymes, glycine amide is somewhat more activating. Essential differences are shown in the chemical and catalytic properties of Cx-exoglucanase and beta-glucosidase. It is found (under the effect of glutaric aldehyde) that amino groups are significant for manifestation of the activities of C1- and C2-cellulases and Cx-endoglucanase and to a less extent for that of Cs-exoglucanase and beta-glucosidase. It is supposed that electrostatic interactions of the carbolytic and amine groups might be an essential factor for stability of C1- and C2-cellulases and Cx-endoglucanase.
D000588:Amines / Q000378:metabolism; D001230:Aspergillus / Q000201:enzymology*; D002480:Cellulase / Q000378:metabolism*; D004024:Dicyclohexylcarbodiimide / Q000494:pharmacology; D004355:Drug Stability; D004789:Enzyme Activation / Q000187:drug effects; D005959:Glucosidases / Q000378:metabolism*; D006026:Glycoside Hydrolases / Q000378:metabolism*; D013329:Structure-Activity Relationship
D000588:Amines; D004024:Dicyclohexylcarbodiimide; D005959:Glucosidases; D006026:Glycoside Hydrolases; D002480:Cellulase
Modyfikatsiia karboksyl'nykh ta aminnykh hrup tseliulolitychnykh fermentiv z Aspergillus awamori