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Covalent coupling of calf brain prolidase
Author(s) -
Hui KoonSea,
Weiss Benjamin,
Hui Maria,
Lajtha Abel
Publication year - 1977
Publication title -
journal of neuroscience research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.72
H-Index - 160
eISSN - 1097-4547
pISSN - 0360-4012
DOI - 10.1002/jnr.490030306
Subject(s) - enzyme , covalent bond , chemistry , free form , sepharose , thermal stability , enzyme assay , stereochemistry , crystallography , biochemistry , organic chemistry , computer graphics (images) , computer science
Calf brain prolidase covalently bound to CNBr‐Sepharose 4B, retained about 32% of the activity of the uncoupled enzyme. The free enzyme showed slightly greater stability than the bound preparation when stored at 20°C or at 0°C. However, in either case the free and bound enzymes were more stable at the lower temperature. Greater thermal stability was shown by the free enzyme than by the bound preparation over a temperature range of 25°C–60°C. The free and bound prolidase, with and without Mn +2 , had maximal activity at pH 4.0. Although the bound enzyme showed a single maximum, the free preparation exhibited three pH maxima of 4.0, 9.0, and 66.8, in decreasing order of activity. The ions Ag + , Cu + , Hg +2 , and Zn +2 were strongly inhibitory on the free enzyme, whereas inhibition of the bound enzyme, with the exception of Zn +2 , was less. Unlike the coupled enzyme, a stimulatory effect was obtained on the free preparation with Co +3 , Mg +2 , and Mn +2 . Various other compounds were studied and their effects were noted.