Characterization of recombinant malarial RecQ DNA helicase

- The first report on the study RecQ DNA helicase from parasites.
- The PfRecQ1was cloned from multi-drug resistant Plasmodium falciparum K1.
- Recombinant, 10xHis tagged PfRecQ1 was expressed and purified from E. coli.
- PfRecQ1 is a homologue of human RECQ1 helicase.
- PfRecQ1 is highly similar to the C-terminal portion of human BLM helicase.

RecQ DNA gene of multi-drug resistant Plasmodium falciparum K1 (PfRecQ1) was cloned, and the recombinant C-terminal-decahistidine-tagged PfRecQ1 was expressed in Escherichia coli. The purified enzyme could efficiently unwind partial duplex DNA substrate in a 3′ to 5′ direction. The malarial RecQ1 could not unwind substrates with both 5′ and 3′ overhangs, those with a 5′ overhang, or blunt-ended DNA duplexes. Unwinding of DNA helicase activity was driven by the hydrolysis of ATP. The drug inhibitory effects of six compounds indicated that only doxorubicin and daunorubicin could inhibit the unwinding activity.

The first report on the study of RecQ DNA helicase from parasites. The recombinant PfRecQ1 was cloned from multi-drug resistant P. falciparum and expressed in E. coli.72