Probing the equatorial groove of the hookworm protein and vaccine candidate antigen, Na-ASP-2.Mason, L., Tribolet, L., Simon, A., von Gnielinski, N., Nienaber, L., Taylor, P., Willis, C., Jones, M.K., Sternberg, P.W., Gasser, R.B., Loukas, A., Hofmann, A.
(2014) Int.J.Biochem.Cell Biol. 50: 146-155
- PubMed: 24631931
- DOI: 10.1016/j.biocel.2014.03.003
- Primary Citation of Related Structures:  4NUK, 4NUN, 4NUO
- PubMed Abstract:
Hookworm activation-associated secreted proteins can be structurally classified into at least three different groups. The hallmark feature of Group 1 activation-associated secreted proteins is a prominent equatorial groove, which is inferred to form ...
Hookworm activation-associated secreted proteins can be structurally classified into at least three different groups. The hallmark feature of Group 1 activation-associated secreted proteins is a prominent equatorial groove, which is inferred to form a ligand binding site. Furthermore, a conserved tandem histidine motif is located in the centre of the groove and believed to provide or support a yet to be determined catalytic activity. Here, we report three-dimensional crystal structures of Na-ASP-2, an L3-secreted activation-associated secreted protein from the human hookworm Necator americanus, which demonstrate transition metal binding ability of the conserved tandem histidine motif. We further identified moderate phosphohydrolase activity of recombinant Na-ASP-2, which relates to the tandem histidine motif. By panning a random 12-mer peptide phage library, we identified a peptide with high similarity to the human calcium-activated potassium channel SK3, and confirm binding of the synthetic peptide to recombinant Na-ASP-2 by differential scanning fluorimetry. Potential binding modes of the peptide to Na-ASP-2 were studied by molecular dynamics simulations which clearly identify a preferred topology of the Na-ASP-2:SK3 peptide complex.
Structural Chemistry Program, Eskitis Institute, Griffith University, Brisbane, Queensland, Australia.