Structure of Fab fragment of malaria transmission blocking antibody 2A8 against P. vivax P25 protein

Comparison of native Fab2A8 structure with antigen bound Fab2A8 structure indicates the significant conformational changes in CDR-H1 and CDR-H3 regions of VH domain and CDR-L3 region of VL domain of Fab2A8. Upon complex formation, the relative orientation between VL and VH domains of Fab2A8 is conserved, while significant differences are observed in elbow angles of heavy and light chains. The combing site residues of complexed Fab2A8 exhibited the reduced temperature factor compared to native Fab2A8, suggesting a loss of conformational entropy upon antigen binding.