Structural Insights Into the Function of Leishmania major Adenylosuccinate Lyase.

One of several intriguing aspects of kinetoplastid biochemistry is the complete dependence on host purines and purine recycling due to the lack of a de novo purine biosynthesis pathway. Adenylosuccinate lyase (ASL, EC 4.3.2.2) is a key enzyme in the purine synthesis pathway responsible for the conversion of adenylosuccinate into adenosine monophosphate (AMP), representing a potential target for an effective drug design against leishmaniasis. Here, we report the in vitro kinetics studies and the crystal structure of the Leishmania major Friedlin adenylosuccinate lyase (LmASL). Furthermore, we characterize allosteric communication networks within the protein. We propose a phenylpiperazine derivative, itraconazole, as a promising candidate for selective interaction with the LmASL substrate-binding site by molecular docking and molecular dynamics simulations. Finally, we expand the current understanding on trypanosomatid ASL by demonstrating its requirement for the normal growth of Trypanosoma brucei procyclic form. Our data will substantiate future studies aimed at developing an effective and specific treatment against leishmaniasis.