|
type |
Journal Article |
authors |
Wu, J. Y. |
title |
Purification and characterization of cysteic acid and cysteine sulfinic acid decarboxylase and L-glutamate decarboxylase from bovine brain |
journal |
Proc Natl Acad Sci U S A |
Activity |
4.1.1.29 |
ui |
83014881 |
year |
(1982) |
volume |
79 |
number |
14 |
pages |
4270-4. |
| |
keywords |
Animal |
abstract |
L-Cysteic and cysteine sulfinic acids decarboxylase (CADCase/CSADCase) and L-glutamic acid decarboxylase (GADCase), the synthetic enzymes for taurine and gamma-aminobutyric acid, respectively, have been purified to homogeneity from bovine brain. Although CADCase/CSADCase and GADCase copurified through various column procedures, these two enzymes can be clearly separated by a hydroxyapatite column. The purification procedures involve ammonium sulfate fractionation, column chromatographies on Sephadex G-200, hydroxyapatite, DEAE-cellulose, and preparative polyacrylamide gel electrophoresis. The Km values for CADCase/CSADCase are 0.22 and 0.18 mM with L-cysteic and cysteine sulfinic acids as substrates, respectively. CADCase/CSADCase cannot use L-glutamate as substrate. GADCase can use L-glutamate, L-cysteic, and cysteine sulfinic acid as substrates with Km values of 1.6, 5.4, and 5.2 mM, respectively. Antibodies against CADCase/CSADCase do not crossreact with GADCase preparations and vice versa. It is concluded that CADCase/CSADCase and GADCase are two distinct enzyme entities and they are responsible for the biosynthesis of taurine and gamma- aminobutyric acid, respectively. |
last changed |
2002/11/12 16:17 |
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