(A) Alignment of P. berghei and P. yoelii P36 protein sequences. Identical, similar and different amino acids are shaded in black, grey and red, respectively. The tandem 6-cys domains D1 and D2 are indicated with blue and green lines, respectively, above the protein sequences. The six cysteine residues of each domain are indicated below the protein sequences. (B) Schematic representation of the tandem D1 and D2 6-cys domains of P36, showing the disulfide bond arrangement. The position of the ‘inter-cys loop’, located between the third and fourth cysteine residues of D2, is indicated as a red line. (C) Alignment of P. falciparum, P. vivax, P. berghei and P. yoelii inter-cys loop sequences. Identical and similar amino acids are shaded in black and grey, respectively.