title: Cysteine Proteases Inhibitors with Immunoglobulin-Like Fold in Protozoan Parasites and their Role in Pathogenesis.
abstract: The number of protein folds in nature is limited, thus is not surprising that proteins with the same fold are able to exert different functions. The cysteine protease inhibitors that adopt an immunoglobulin- like fold (Ig-ICPs) are inhibitors encoded in bacteria and protozoan parasites. Structural studies indicate that these inhibitors resemble the structure of archetypical proteins with an Ig fold, like antibodies, cadherins or cell receptors. The structure of Ig-ICPs from four different protozoan parasites clearly shows the presence of three loops that form part of a protein-ligand interaction surface that resembles the antigen binding sites of antibodies. Thus, Ig-ICPs bind to different cysteine proteases using a tripartite mechanism in which their BC, DE and FG loops are responsible for the main interactions with the target cysteine protease. Ig-ICPs from different protozoan parasites regulate the enzymatic activity of host or parasite's proteases and thus regulate virulence and pathogenesis.
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 629, CP 36821, Irapuato, Guanajuato. Mexico.
authors.forename: Pedro
authors.initials: P
authors.lastname: Jimenez-Sandoval
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 629, CP 36821, Irapuato, Guanajuato. Mexico.
authors.forename: Laura Margarita
authors.initials: LM
authors.lastname: Lopez-Castillo
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 629, CP 36821, Irapuato, Guanajuato. Mexico.
authors.forename: Carlos H
authors.initials: CH
authors.lastname: Trasviña-Arenas
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 629, CP 36821, Irapuato, Guanajuato. Mexico.
authors.forename: Luis G
authors.initials: LG
authors.lastname: Brieba
mesh_terms: D001665:Binding Sites; D015853:Cysteine Proteinase Inhibitors / Q000737:chemistry* / Q000378:metabolism; D004748:Entamoeba histolytica / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D015870:Gene Expression; D007136:Immunoglobulins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D007894:Leishmania mexicana / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D008024:Ligands; D010963:Plasmodium falciparum / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D011485:Protein Binding; D000072756:Protein Conformation, alpha-Helical; D000072757:Protein Conformation, beta-Strand; D017510:Protein Folding; D054730:Protein Interaction Domains and Motifs; D015800:Protozoan Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D014349:Trypanosoma cruzi / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D014774:Virulence
chemical_list: D015853:Cysteine Proteinase Inhibitors; D007136:Immunoglobulins; D008024:Ligands; D015800:Protozoan Proteins
keywords: Immunoglobulin fold; cysteine protease inhibitors; cysteine proteases; evolution; parasites; pathogenesis