Identification of a new Schistosoma mansoni membrane-bound protein through bioinformatic analysis.

Progress in schistosome genome research has enabled investigators to move rapidly from genome sequences to vaccine devel- opment. Proteins bound to the surface of parasites are potential vaccine candidates, or they can be used for diagnosis. We analyzed 4342 pro- teins deduced from the Schistosoma mansoni transcriptome with bioinformatic computer programs. Thirty-four proteins had membrane- bound motifs. Within this group, we selected the Sm29 protein to be further characterized by in silico analysis. Sm29 was found to have a signal peptide made up of 26 amino acids, with a cleavage site between Ser26 and Val27. The glycosylation site search revealed three threonines (39, 132 and 133) with high probability of O-glycosylation and two as- paragines (58 and 115) with high probability of N-glycosylation. Only one transmembrane helix was found in the C-terminal region of the pro- tein from Leu169 to Lis191. The search for similarities and conserved motifs show that Sm29 is a protein with high identity to proteins present in S. japonicum (53, 52, 49, and 37% of identity) and it possesses disul- fide-rich conserved domains. Apparently, Sm29 is a membrane bound