Comparative genomics for the identification of recq dna helicases in protozoan parasites

DNA helicases are essential enzymes that catalyze the unwinding of DNA substrates in an energy-dependent manner, participating in all the molecular processes involving DNA. They are characterized by the presence of a conserved helicase domain with eight well defined motifs including motif 0, as well as RecQ-Ct and HDRC domains. The conservation of these domains through evolutionary scale can be successfully used in a bioinformatics approach to identify new homologues in any genome sequence database. In this chapter, we focused on the fully sequenced genome of Entamoeba histolytica, Giardia lamblia, Trichomonas vaginalis and Plasmodium falciparum protozoan parasites, which cause high morbidity and mortality in many developed and developing countries. The identification of parasite RecQ DNA helicases and their further functional characterization will provide new insights into the molecular biology of these major human pathogens.