Autor: |
Hopkins MH; Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113., Bichler KA, Su T, Chamberlain CL, Silverman RB |
Jazyk: |
angličtina |
Zdroj: |
Journal of enzyme inhibition [J Enzyme Inhib] 1992; Vol. 6 (3), pp. 195-9. |
DOI: |
10.3109/14756369209020169 |
Abstrakt: |
It is hypothesized that buffers capable of forming a Schiff base with the PLP of gamma-aminobutyric acid aminotransferase (GABA-AT) may lead to denaturation and inactivation of the enzyme. On the basis of this hypothesis three new methods for the selective destruction of GABA-AT in GABAse (a commercial bacterial source of a mixture of GABA-AT and succinic semialdehyde dehydrogenase [SSDH]) and from pig brain are described: (1) dialysis against a primary or secondary amine buffer; (2) gel filtration with a primary or secondary amine buffer as eluent; (3) inactivation with gabaculine followed by dialysis or gel filtration with pyrophosphate buffer. The SSDH activity in GABAse, which remains unchanged by all of these methods, may then be used in a coupled assay to measure the activity of GABA-AT from different sources. These results also suggest that the use of primary and secondary amine buffers should be avoided when inhibitors are being tested with GABA-AT. |
Databáze: |
MEDLINE |
Externí odkaz: |
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