The DBL2β-PfEMP1 is an adhesive domain of Plasmodium falciparum, which is important for malaria pathogenesis. In this study, the DBL2β-PfEMP1 from the Indonesian isolate of Plasmodium falciparum was cloned and the protein structure prediction of the DBL2β recombinant protein as well as its ligand binding sites was carried out. The DBL2β recombinant protein consists of 1674 nucleotides which are translated into 558 amino acids. Analysis using Expasy ProtParam tool showed that the protein had a MW of 64.69 kDa with an isoelectric point of 8.82. It had 83 negatively charged residues (Asp + Glu) and 98 positively charged residues (Arg + Lys). It was classified as an unstable protein because it had an instability index of 40.01. Protein structure prediction of the DBL2β recombinant protein and its binding sites was carried out using the I-TASSER program. It showed that the DBL2β recombinant protein had the highest significant alignment with the DBLβ domain of PF11_0521 PfEMP1, which is bound to the human ICAM-1, but the protein had the closest structural similarity with the of EBA-175 Region II (RII) of P. falciparum, where the protein functions as the cell invasion molecule. The highest C-score of ligand-binding site was 0.10 for the PEPTIDE ligand (GLN, LEU, ASP, PHE, GLU, ASP, VAL, TRP, ASN, SER, SER, TYR), and the ligand-binding site residues were at 84, 87, 88, 91, 92, 95, 99, 196, 199, 200, 203, 206. It is likely that the DBL2β recombinant protein has the major function as an adhesion molecule for invasion to the host. Further studies on its role in in vivo models are needed to develop a definite conclusion.
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