Structural and Biochemical Features of Eimeria tenella Dihydroorotate Dehydrogenase, a Potential Drug Target.

Dan Sato,Tomoyoshi Nozaki,Makoto Matsubayashi,Shigeharu Harada,Madoka Nagahama,Kiyoshi Kita,Takaya Sakura,Tomoo Shiba,Daniel Ken Inaoka,Yukina Yoshioka,Endah Dwi Hartuti,Eri Amalia,Naotoshi Tsuji

doi:10.3390/genes11121468

Abstract

Dihydroorotate dehydrogenase (DHODH) is a mitochondrial monotopic membrane protein that plays an essential role in the pyrimidine de novo biosynthesis and electron transport chain pathways. In Eimeria tenella, an intracellular apicomplexan parasite that causes the most severe form of chicken coccidiosis, the activity of pyrimidine salvage pathway at the intracellular stage is negligible and it relies on the pyrimidine de novo biosynthesis pathway. Therefore, the enzymes of the de novo pathway are considered potential drug target candidates for the design of compounds with activity against this parasite. Although, DHODHs from E. tenella (EtDHODH), Plasmodium falciparum (PfDHODH), and human (HsDHODH) show distinct sensitivities to classical DHODH inhibitors, in this paper, we identify ferulenol as a potent inhibitor of both EtDHODH and HsDHODH. Additionally, we report the crystal structures of EtDHODH and HsDHODH in the absence and presence of ferulenol. Comparison of these enzymes showed that despite similar overall structures, the EtDHODH has a long insertion in the N-terminal helix region that assumes a disordered configuration. In addition, the crystal structures revealed that the ferulenol binding pocket of EtDHODH is larger than that of HsDHODH. These differences can be explored to accelerate structure-based design of inhibitors specifically targeting EtDHODH.

Highlights

Poultry industries are among the most important animal food resources, and their global production has tripled in a quarter-century (FAO, 2015)
We recently reported that ascofuranone, an antibiotic isolated from Acremonium egiptiacum [26], and its synthetic derivatives are potent inhibitors of HsDHODH
The N-terminal extension found in Dihydroorotate dehydrogenase (DHODH) from other apicomplexan parasites, such as P. falciparum, T. gondii, and Neospora caninum, is not conserved in E. tenella DHODH (EtDHODH)

Summary

Introduction

Poultry industries are among the most important animal food resources, and their global production has tripled in a quarter-century (FAO, 2015). Pathogens infecting chickens pose serious threats to world food security because such pathogens lead to reduced productivity. Poultry coccidiosis has the greatest economic impact on productivity because of high infectivity and mortality [1], with an estimated annual worldwide economic loss of 2 billion dollars. Amongst the seven Eimeria species that are known to infect chickens, Eimeria tenella infection has the greatest impact in global agro-economics due to this pathogen’s high virulence [3]. The immune strategy can reduce the severity of diseases, it does not inhibit the infections, resulting in oocyst shedding in feces as potential sources of new infection and spread [3]. The development of new prophylactic modalities is indispensable for satisfactory prevention (or eradication) of the disease, e.g., suppressing the infections and possessing non-toxic and protozoan-specific effects

Methods

Results

Discussion

Conclusion