Optimization of CIDR1α-PfEMP1 Gene Transformation in Eschericia coli BL21(DE3) by Heat-shock Method: Stages of Malaria Vaccine Development

Abstract

Malaria is still a world health problem, especially in developing countries. Data from the World Malaria Report 2020, malaria cases in the world in 2019 reached 229 million cases with a total death of 409,000 people. The highest mortality occurred in patients under five, which reached 272,000 people. The high mortality rate of severe malaria worldwide needs multiple approaches including the malaria vaccine. Cysteine-rich Interdomain Regions 1α-Plasmodium falciparum Erythrocyte Membrane Protein 1 (CIDR1α-PfEMP1) is a candidate for malaria vaccine due to its important role in malaria pathogenesis. The development of CIDR1α-PfEMP1-based malaria vaccine is conducted by DNA recombinant technology where transformation is a pivotal step. The study aimed to optimize the transformation of CIDR1α-PfEMP1 into Escherichia coli BL21(DE3) using heat shock method to find out the highest transformation efficiency. The variables were duration of heat shock in 30, 50, and 70 secs and plating volume of 100 µL and 200 µL. The results showed that the highest transformation efficiency was 1.9 x 102 CFU/µg, it was achieved by 50 secs heat shock and 200 µL plating volume. This was an optimum transformation condition that can be used further for cloning of CIDR1α-PfEMP1 gene to develop a malaria vaccine.