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IMMUNOCHEMICAL STUDIES ON GLUTAMIC ACID DECARBOXYLASE (EC 4.1.1.15) FROM MOUSE BRAIN 1
Author(s) -
Matsuda T.,
Wu J.Y.,
Roberts E.
Publication year - 1973
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1111/j.1471-4159.1973.tb04235.x
Subject(s) - glutamate decarboxylase , antiserum , ouchterlony double immunodiffusion , precipitin , pyridoxal phosphate , enzyme , pyridoxal , biochemistry , chemistry , glutamic acid , specific activity , enzyme assay , microbiology and biotechnology , antibody , biology , amino acid , cofactor , immunology
Purified homogenous glutamic acid decarboxylase (GAD) from mouse brain and rabbit antiserum prepared to partially purified GAD gave only one sharp precipitin band in the Ouchterlony double diffusion test. GAD activity was inhibited partially by incubating with the antiserum. The maximal extent of inhibition was approximately 50 per cent. In the presence of antiserum all enzyme activity could be precipitated. The precipitates formed by GAD and antiserum had about 50 per cent of the enzyme activity and the K m values for both glutamic acid and pyridoxal phosphate were significantly higher than those of the control system. Pyridoxal phosphate protected GAD from inhibition only slightly, even at very high concentrations. The results suggest that the antibodies may not react with the catalytic site, but rather that the inhibition of enzyme activity is attributable to indirect effects.