Mechanistic underpinnings of substrate recognition, catalysis and allostery in GMP synthetases

Abstract

This chapter introduces the reader to the glutamine amidotransferase (GAT) family of enzymes. A brief overview of the reaction catalyzed by these enzymes and the highlights of functioning are presented. This is followed by a summary of the published biochemical and structural information on nine GATs belonging to a sub-family called triad GATs. This includes an in-depth discussion on GMP synthetases (GMPS), a triad GAT investigated in this graduate work. For each enzyme, an attempt is made to highlight the current status in the understanding of various functional aspects. The objectives of this graduate work are laid out in the final section based on the many lacunae that exist in the mechanistic understanding of GMPSs.