We found in the database from the S. mansoni transcriptome project an EST with partial identity to the SmATPDase1 nucleotide sequence, previously described to code for an enzyme localized on the parasite’s tegument. From this information it was possible to clone the full-length gene sequence using RACE methods and sequencing. The DNA sequence that codes for SmATPDase2 mature enzyme was cloned after PCR amplification using as template cDNA made from adult worm mRNA. In silico analyses showed that the cloned sequence will code for a 564 aa enzyme, without signal peptide and with a single transmembrane region localized at the N-terminal end, similar to human NTPDase 6. In contrast, SmATPDase1 and human NTPDase 1 have two transmembrane regions one at the N-terminal and another at the carboxy-end.  The primary structures from both ATPDases 1 and 2 have the five known conserved ATPDase domains, however they possess a region between conserved motifs 4 and 5 with very low identity between them. From this information we sub-cloned these regions and expressed them in E. coli BL21(DE3) as fusion proteins with histidine tag. The recombinant proteins purified in Ni-NTA columns were about 20 kDa each. They were dialyzed against PBS and the fragments obtained from SmATPDase 1 and 2 were injected into mice and rabbit, respectively. The anti-sera from mice and rabbit were purified by adsorption using inclusion bodies from bacteria expressing SmATPDase1 fragment against serum anti-SmATPDase2 and vice-versa. This procedure was adopted because in western blot assays both anti-sera had shown cross-reaction with the two isoforms, indicating the presence of antibodies against common epitopes and histidine tag. Adsorbed antibodies showed no cross-reactivity in Western blots. With these improved antibodies we performed immunolocalization assays using fluorescence confocal microscopy in fixed adult worm sections and miracidia and cercariae. We found that SmATPDase2 was localized on the tegument, similar to SmATPDase1. In miracidia permeabilized with detergent SmATPDase2 was found more concentrated at a region on the surface. SmATPDase2 expression analyses by Real-Time RT-PCR showed the presence of SmATPDase2 message in the egg, miracidium, cercaria, schistosomulum and adult stages.