Kinetic characterization of GABA-transaminase from cultured neurons and astrocytes
- 1 November 1990
- journal article
- Published by Springer Nature in Neurochemical Research
- Vol. 15 (11) , 1073-1077
- https://doi.org/10.1007/bf01101706
Abstract
The enzymatic mechanism and the kinetic parameters of GABA-transaminase extracted from cultured mouse cerebral cortex neurons and astrocytes were studied. Neuronal as well as astrocytic GABA-transaminase obeyed a bi bi ping-pong reaction mechanism. The estimated Km-values for α-ketoglutarate and GABA were significantly lower for astroglial GABA-transaminase compared to the neuronal enzyme suggesting a possible existence of cell specific isozymes of GABA-transaminase. The observed enzymatic mechanism and the magnitude of the estimated kinetic parameters imply that GABA-transaminase synthesized in the two types of cultured neural cells is mechanistically and kinetically equivalent to the enzyme synthesized in the brainin vivo.Keywords
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