Cloning, expression and dynamic simulation of TRYP6 from Leishmania major (MRHO/IR/75/ER).

Leishmania, a digenetic protozoan parasite causes severe diseases in human and animals. Efficient evasion of toxic microbicidal molecules, such as reactive oxygen species and reactive nitrogen species is crucial for Leishmania to survive and replicate in the host cells. Tryparedoxin peroxidase, a member of peroxiredoxins family, is vital for parasite survival in the presence of antioxidant, hence it is one of the most important molecules in Leishmania viability and then, it may be an appropriate goal for challenging against leishmaniasis. After cloning and sub-cloning of TRYP6 from Leishmania major (MRHO/IR/75/ER), homology modeling of the LmTRYP6 was proposed to predict some functional property of this protein. The refined model showed that the core structure consists of a seven β stranded β-sheet and five α helices which are organized as a central 7-stranded β2-β1-β5-β4-β3-β6-β7 surrounded by 2-stranded β-hairpin, α helices A and D on one side, and α helices B, C and E on the other side. The peroxidatic active site is located in a pocket formed by the residue Pro45, Met46, Thr49, Val51, Cys52, Arg128, Met147 and Pro 148. The catalytic Cys52, located in the first turn of helix αB, is in van der Waals with a Pro45, a Thr49 and an Arg128 that are absolutely conserved in all known Prx sequences. In this study, an attractive molecular target was studied. These results might be used in designing of drugs to fight an important human pathogen.