Article

Leishmania infantum chagasi: A genome-based approach to identification of excreted/secreted proteins

Department of Internal Medicine, University of Iowa, Iowa City, IA 52242, USA.
Experimental Parasitology (Impact Factor: 1.86). 12/2010; 126(4):582-91. DOI: 10.1016/j.exppara.2010.06.011
Source: PubMed

ABSTRACT The parasitic protozoan, Leishmania, survives in harsh environments within its mammalian and sand fly hosts. Secreted proteins likely play critical roles in the parasite's interactions with its environment. As a preliminary identification of the spectrum of potential excreted/secreted (ES) proteins of Leishmania infantum chagasi (Lic), a causative agent of visceral leishmaniasis, we used standard algorithms to screen the annotated L. infantum genome for genes whose predicted protein products have an N-terminal signal peptide and lack transmembrane domains and membrane anchors. A suite of 181 candidate ES proteins were identified. These included several that were documented in the literature to be released by other Leishmania spp. Six candidate ES proteins were selected for further validation of their expression and release by different parasite stages. We found both amastigote-specific and promastigote-specific released proteins. The ES proteins of Lic are candidates for future studies of parasite virulence determinants and host protective immunity.

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Available from: Selma M B Jeronimo, Nov 12, 2014
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    • "In another recently study, L. infantum chagasi-excreted/secreted proteins were predicted using a genome-based approach (DebRoy et al., 2010). This was done screening the annotated L. infantum genome for genes, whose predicted protein products have an Nterminal secretion signal peptide and lack transmembrane domains and membrane anchors. "
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    • "However, of the seven reports on Leishmania secreted proteins, only one found that a large proportion of the secreted proteins identified contained an N-terminal secretion signal peptide for classical secretion (Paape et al., 2010). In all of the remaining reports, the authors observed the opposite to be true, with a majority of secretome proteins lacking a secretion signal peptide (Revest et al., 2008; Silverman et al., 2008, 2010a; DebRoy et al., 2010; Kima et al., 2010; Hassani et al., 2011). Three of the seven reports which investigated alternative mechanisms of secretion identified vesicles secreted by Leishmania (Silverman et al., 2008, 2010a; Hassani et al., 2011). "
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