Gabaculine transaminase

The proposed mechanism of inactivation is depicted in Figure 13. It is reminiscent of that proposed for the inactivation of 7 aminobutyric acid transaminase by gabaculine or cycloserine. ... 

Fig. 7. Mechanism proposed for inactivation of GABA transaminase by gabaculine (8).

Bernasconi R, Maitre L, Martin P, and Raschdorf F (1982) The use of inhibitors of GABA-transaminase for the determination of GABA turnover in mouse brain regions an evaluation of ammooxyacetic acid and Gabaculine. / Neurochem. 38, 57-66. 

Matsui Y. and Deguchi T (1977) Effects of Gabaculine, a new potent inhibitor of gamma-ammobutyrate transaminase, on the bram gam-ma-aminobutyrate content and convulsions in mice Life Sci 20, 1291-1296... 

Rando R. R and Bangerter F. W (1977) The in vivo inhibition of GABA transaminase by Gabaculine. Biochem Biophys Res Commun 76, 1276-1281. 

This molecule specifically and irreversibly inhibits y-aminobutyrate-a-ketoglutarate transaminase. The Ki for this molecule is 2.8 ixM, some three orders of magnitude lower than the Km for the natural substrate, y-aminobutyrate. The ti/2 for inactivation of the bacterial enzyme is 9 min at 0.3 fuM gabaculine. As expected, gabaculine is not an irreversible inhibitor of the enzyme in the pyridoxamine form, and the mechanism of the irreversible inhibition by gabaculine is completely in accord with the hypothesis that enzymic conversion before inhibition. The possible mechanisms proposed for the inhibition are those in Eq. (5). ... 

Gabaculine, see l,3-Cyclohexadienyl-5-aminocarboxylic acid GABA transaminase, see v-Aminobuty-rate-a-ketoglutarate transaminase D-Galaotal, 26... 

Gabaculine (3-amino-2,3-dihydrobenzoic acid) is a potent mechanism-based inhibitor of certain pyridoxal phosphate-linked enzymes. " " In plants, it is a potent inhibitor of chlorophyll biosynthesis the inhibition can be reversed by Gabaculine and another transaminase... 

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