Thermal stabilization of trypsin by enzymic modification with beta-cyclodextrin derivatives.
Streptoverticillum sp. transglutaminase was used as catalyst for the attachment of several beta-cyclodextrin derivatives to the glutamine residues in bovine pancreatic trypsin. The modifying agents used were mono-6-ethylenediamino-6-deoxy-beta-cyclodextrin, mono-6-propylenediamino-6-deoxy-beta-cyclodextrin, mono-6-butylenediamino-6-deoxy-beta-cyclodextrin and mono-6-hexylenediamino-6-deoxy-beta-cyclodextrin. The transformed trypsin preparations contained about 3 mol of oligosaccharides/mol of protein. The specific esterolytic activity of trypsin was increased by about 4-21% after conjugation. The K (m) values for cyclodextrin-trypsin complexes represented about 58-87% of that corresponding to the native enzyme. The optimum temperature for esterolytic activity of trypsin was increased by about 5-10 degrees C after enzymic modification with the cyclodextrin derivatives. The thermostability was increased by 16 degrees C for the modified trypsin. Thermal inactivation at different temperatures ranging from 45 to 60 degrees C was markedly increased for the oligosaccharide-trypsin complexes. This modification also protected the enzyme against autolysis at alkaline pH.
Villalonga
Reynaldo
R
Enzyme Technology Group, Center for Biotechnological Studies, University of Matanzas, Autopista a Varadero km 3 1/2, Matanzas, C.P. 44740, Cuba. reynaldo.villalonga@umcc.cu
Fernández
Michael
M
Fragoso
Alex
A
Cao
Roberto
R
Mariniello
Loredana
L
Porta
Raffaele
R
D000818:Animals; D002417:Cattle; D003505:Cyclodextrins / Q000138:chemical synthesis / Q000737:chemistry*; D004789:Enzyme Activation; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010179:Pancreas / Q000201:enzymology; D012680:Sensitivity and Specificity; D013696:Temperature; D014357:Trypsin / Q000737:chemistry*; D047392:beta-Cyclodextrins
D003505:Cyclodextrins; D047392:beta-Cyclodextrins; D014357:Trypsin; C031215:betadex