doi:10.1038/nindia.2014.42 Published online 31 March 2014
Scientists have genetically engineered a synthetic helicase — an enzyme that can unpackage genetic material such as DNA and RNA — from the malarial parasite Plasmodium falciparum. The study will advance our knowledge of the unwinding mechanism of helicases .
Helicases unwind duplex nucleic acids by utilizing the energy of nucleoside triphosphate hydrolysis. Scientists at the International Centre for Genetic Engineering and Biotechnology (ICGEB) in New Delhi had earlier reported that helicases could serve as potential novel drug targets for the control of malaria. The researchers reported the characterization of parasite-specific UvrD helicase from P. falciparum. They showed that the N-terminal and C-terminal fragments of PfUvrD contain characteristic ATPase and DNA helicase activities.
Now, the ream has reported the generation and characterization of a genetically engineered version of PfUvrD and its derivatives. The miniaturized version synthetic UvrD (sUD) helicase of ~45 kDa containing all the conserved motifs was constructed through genetic engineering. The miniature version of the naturally occurring enzyme retains all characteristic enzymatic activities.
"This synthetic enzyme and one of its smallest derivatives sUDN1N2 of ~22 kDa exhibit the ATPase and ATP-dependent 3' to 5' DNA unwinding activities. The mutants of sUD and sUDN1N2 were produced by substituting two amino acids in the conserved helicase motifs", says lead researcher Renu Tuteja.