Malaria kills thousands of people every year and researchers have been constantly in search of effective treatments. Researchers may soon add one more weapon to the fight against malaria by blocking a key protein in the parasite that prevents it from completing its life-cycle.
Malaria is caused by Plasmodium parasites that are transmitted through Anopheles mosquitoes. It has a complex life cycle that requires a host (human) and a vector (something that transmits the disease, in this case a mosquito). After infection, it takes the parasite spermatozoids about 30 minutes to find and enter the human liver. The parasite then develops into thousands of merozoites, a stage in the development of the parasite. These merozoites then enter blood stream and infect cells there.
When a mosquito bites a human, the parasites are transferred into a human's bloodstream via the mosquito's saliva. Here, the parasite enters a stage where it gets the ability to invade gut walls of its host. The research team found that blocking the parasite's activity at this crucial stage could stop the parasites from spreading.
The team included researchers from University of Nottingham, University of Oxford and Imperial College, London along with other research centers in UK.
They found that removing an enzyme called, PPKL phosphatise, disrupted the activity of many proteins in the parasite.
"This is the first step in understanding the functional role of phosphatases in malaria. This enzyme is absent in humans and so it can be explored as a good target for malaria control and transmission. The control of parasite transmission is important in order to prevent the spread of malaria. Targeting PPKL can be an important player in this process," said Dr. Rita Tewari in the Centre for Genetics and Genomics in the School of Biology. Tewari is the lead author of the study.
The parasite gets the ability to invade the gut wall after it becomes an ookinete. It is in this stage where the parasite is shaped like a banana. Blocking the key enzyme stops the parasite from developing into this banana structure and as a result the parasite loses its ability to enter the gut wall.
"Transmission through the mosquito represents a bottle neck in the parasite's life cycle. Intervention strategies to target these stages will be essential for the long term goal to eradicate and finally eliminate malaria," said Tony Holder, Head of Parasitology at the MRC National Institute for Medical Research UK and one of the study authors.
The study has been published in the open-access journal PLOS Pathogens.