FIRST FABP FROM NEMATODES WITH SOLVED STRUCTURE, REVEALS NOVEL MODIFICATIONS AMONG THE LBP SUPERFAMILY

IBAÑEZ SHIMABUKURO M; REY BURUSCO F; COOPER A; KENNEDY MW; SMITH BO; B. CÓRSICO

La Plata

Congreso; 8th International Conference on Lipid Binding Proteins (8ICLBP); 2013

LBPS

As-p18 is produced and secreted by larvae of the parasitic nematode Ascaris suum as they develop within their eggs [1]. The protein is a member of the fatty acid binding protein (FABP) family found in a wide range of eukaryotes, but is distinctive in that it possesses a secretory signal, determining its secretion from the synthesizing cell; and has predicted structural features not previously seen in other FABPs. As-p18 and similar proteins found only in nematodes have therefore been designated ?nemFABPs?. Solution NMR structure was established for the 155 amino acid recombinant protein (18.3 kDa) in complex with oleic acid, using a series of three-dimensional heteronuclear experiments [2]. Although the overall structure was found to be in accordance with the canonical FABP fold, As-p18 presented extended loops that have not been observed in other FABPs whose structures have so far been solved. We also present a phylogenetic analysis and ligand-binding properties of this nemFABP highlighting the exclusive features which could be relevant for understanding this protein´s role in A. suum infective eggs, and more generally the nemFABP cluster.