A pentapeptide signature motif plays a pivotal role in Leishmania DNA topoisomerase IB activity and camptothecin sensitivity

► We have performed a functional analysis of leishmanial DNA topoisomerase IB. ► Constructs were assayed on relaxation activity and sensitivity to camptothecin. ► Amino acids 175 to 180 of the small subunit play a pivotal role in enzyme activity. ► RPPVV pentapeptide motif is responsible for CPT sensitivity in the small subunit.