Stabilization of alpha-chymotrypsin by modification with beta-cyclodextrin derivatives.
Bovine pancreatic alpha -chymotrypsin was chemically modified with two different beta -cyclodextrin derivatives, named mono-6-formyl-beta-cyclodextrin and mono-6-succinyl-6-deoxy-beta-cyclodextrin. The modified enzymes contained approx. 3-5 mol of oligosaccharide/mol of protein, and retained full proteolytic and esterolytic activity. The optimum temperature for alpha -chymotrypsin was increased by 8 degrees C and its thermostability was enhanced by about 4-6 degrees C after modification. The conjugated enzymes were also more resistant to thermal inactivation at temperatures ranging from 45 to 55 degrees C. Additionally, the modified enzymes were 7-fold more stable against incubation at pH 9.0. The possible influence of supramolecular interactions on the thermal stabilization of modified alpha -chymotrypsins was also studied.
Fernández
Michael
M
Enzyme Technology Group, Center for Biotechnological Studies, University of Matanzas, Matanzas, C.P. 44740, Cuba.
Villalonga
María de Lourdes
Mde L
Fragoso
Alex
A
Cao
Roberto
R
Villalonga
Reynaldo
R
D000818:Animals; D002417:Cattle; D002918:Chymotrypsin / Q000737:chemistry*; D003505:Cyclodextrins / Q000737:chemistry*; D004789:Enzyme Activation; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D046911:Macromolecular Substances; D010179:Pancreas / Q000201:enzymology; D011487:Protein Conformation; D012680:Sensitivity and Specificity; D013696:Temperature; D047392:beta-Cyclodextrins
D003505:Cyclodextrins; D046911:Macromolecular Substances; D047392:beta-Cyclodextrins; D002918:Chymotrypsin; C117608:alpha-chymotrypsin; C031215:betadex