Characterization and validation of Entamoeba histolytica pantothenate kinase as a novel anti-amebic drug target

Publication date: Available online 1 March 2018 Source:International Journal for Parasitology: Drugs and Drug Resistance Author(s): Arif Nurkanto, Ghulam Jeelani, Takehiro Yamamoto, Yoshiko Naito, Takako Hishiki, Mihoko Mori, Makoto Suematsu, Kazuro Shiomi, Tetsuo Hashimoto, Tomoyoshi Nozaki Coenzyme A (CoA), as a cofactor involved in >100 metabolic reactions, is essential to the basic biochemistry of life. Here, we investigated the CoA biosynthetic pathway of Entamoeba histolytica (E. histolytica), an enteric protozoan parasite responsible for human amebiasis. We identified four key enzymes involved in the CoA pathway: pantothenate kinase (PanK, EC 2.7.1.33), bifunctional phosphopantothenate-cysteine ligase/decarboxylase (PPCS-PPCDC), phosphopantetheine adenylyltransferase (PPAT) and dephospho-CoA kinase (DPCK). Cytosolic enzyme PanK, was selected for further biochemical, genetic, and phylogenetic characterization. Since E. histolytica PanK (EhPanK) is physiologically important and sufficiently divergent from its human orthologs, this enzyme represents an attractive target for development of novel anti-amebic chemotherapies. Epigenetic gene silencing of PanK resulted in a significant reduction of PanK activity, intracellular CoA concentrations, and growth retardation in vitro, reinforcing the importance of this gene in E. histolytica. Furthermore, we screened the Kitasato Natural Products Library for inhibitors of recombinant EhPanK, and identified 14 such...
Source: International Journal for Parasitology: Drugs and Drug Resistance - Category: Parasitology Source Type: research