Probing the steric requirements of the γ-aminobutyric acid aminotransferase active site with fluorinated analogues of vigabatrin
作者:Jose I. Juncosa、Andrew P. Groves、Guoyao Xia、Richard B. Silverman
DOI:10.1016/j.bmc.2012.12.009
日期:2013.2
We have synthesized three analogues of 4-amino-5-fluorohexanoic acids as potential inactivators of gamma-aminobutyric acid aminotransferase (GABA-AT), which were designed to combine the potency of their shorter chain analogue, 4-amino-5-fluoropentanoic acid (AFPA), with the greater enzyme selectivity of the antiepileptic vigabatrin (Sabril (R)). Unexpectedly, these compounds failed to inactivate or inhibit the enzyme, even at high concentrations. On the basis of molecular modeling studies, we propose that the GABA-AT active site has an accessory binding pocket that accommodates the vinyl group of vigabatrin and the fluoromethyl group of AFPA, but is too narrow to support the extra width of the distal methyl group in the synthesized analogues. (C) 2012 Elsevier Ltd. All rights reserved.