Reconstruction of Metabolic Pathways for the Setaria digitata Whole Genome

Abstract

INTRODUCTION AND OBJECTIVES: Setaria digitata is a Wolbachia-free filarial parasite that resides in the abdominal cavity of ungulates. It can cause cerebrospinal nematodiasis (CNS) in unnatural hosts such as sheep, goats, which causes a serious threat to livestock farming. Furthermore, S. digitata can also infect humans causing several conditions showing a gradual adaption to humans. METHODS: Despite, to date, complete a metabolic pathway reconstruction of S. digitata has not been undertaken and therefore, in this study the latter analyses were carried out using BLAST2GO software. RESULTS: Metabolic pathway analysis based on Kyoto Encyclopedia of Genes and Genomes (KEGG) database identified 111 enzymes found in total of 246 contigs that involve in 95 metabolic pathways, in which the most over-represented pathways are Biosynthesis of antibiotics, Phosphatidylinositol signaling system and Purine metabolism. Since S. digitata does not harbor Wolbachia endosymbiont, it was theorized that the S. digitata genome must encodes genes to carryout haem, riboflavin and nucleotides pathways, otherwise encoded by Wolbachia genome, potentially through lateral transfer of Wolbachia to an ancestor of S.digitata. Here, KEGG analysis identified 16 enzyme coding genes involve in nucleotide biosynthesis and one enzyme involve in riboflavin biosynthesis pathway. Although studies have revealed that FAD and glutathione pathways are complete in all nematode genomes, the genes encoding FAD and glutathione pathways were not found in the S. digitata. Moreover, complete nucleotide synthesis pathway and haem synthesis pathway were not found. CONCLUSION: This suggests that S. digitata may have evolved its own sequences to encode those biosynthetic pathways and hence calling for investigations to undertake characterization of genes involved in these pathways.