title: Pyruvate:ferredoxin oxidoreductase (PFO) is a surface-associated cell-binding protein in Trichomonas vaginalis and is involved in trichomonal adherence to host cells.
abstract: The Trichomonas vaginalis 120 kDa protein adhesin (AP120) is induced under iron-rich conditions and has sequence homology with pyruvate:ferredoxin oxidoreductase A (PFO A), a hydrogenosomal enzyme that is absent in humans. This homology raises the possibility that, like AP120, PFO might be localized to the parasite surface and participate in cytoadherence. Here, the cellular localization and function of PFO that was expressed under various iron concentrations was investigated using a polyclonal antibody generated against the 50 kDa recombinant C-terminal region of PFO A (anti-PFO50). In Western blot assays, this antibody recognized a 120 kDa protein band in total protein extracts, and proteins with affinity to the surface of HeLa cells from parasites grown under iron-rich conditions. In addition to localization that is typical of hydrogenosomal proteins, PFOs that were expressed under iron-rich conditions were found to localize at the surface. This localization was demonstrated using immunofluorescence and co-localization assays, as well as immunogold transmission electron microscopy. In addition to describing its enzyme activity, we describe a novel function in trichomonal host interaction for the PFO localized on the parasite surface. The anti-PFO50 antibody reduced the levels of T. vaginalis adherence to HeLa cell monolayers in a concentration-dependent manner. Thus, T. vaginalis PFO is an example of a surface-associated cell-binding protein that lacks enzyme activity and that is involved in cytoadherence. Additionally, PFO behaves like AP120 in parasites grown under iron-rich conditions. Therefore, these data suggest that AP120 and PFO A are encoded by the same gene, namely pfo a.
authors: Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), México DF, Mexico.
authors: Patricia
authors: P
authors: Meza-Cervantez
authors: Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), México DF, Mexico.
authors: Arturo
authors: A
authors: González-Robles
authors: Departamento de Biotecnología y Bioingeniería, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), México DF, Mexico.
authors: Rosa Elena
authors: RE
authors: Cárdenas-Guerra
authors: Departamento de Biotecnología y Bioingeniería, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), México DF, Mexico.
authors: Jaime
authors: J
authors: Ortega-López
authors: Departamento de Bioquímica, Instituto Nacional de Cardiología, México DF, Mexico.
authors: Emma
authors: E
authors: Saavedra
authors: Departamento de Bioquímica, Instituto Nacional de Cardiología, México DF, Mexico.
authors: Erika
authors: E
authors: Pineda
authors: Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), México DF, Mexico.
authors: Rossana
authors: R
authors: Arroyo
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D004847:Epithelial Cells / Q000469:parasitology; D005260:Female; D006367:HeLa Cells; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D008856:Microscopy, Fluorescence; D016253:Microscopy, Immunoelectron; D008969:Molecular Sequence Data; D050743:Pyruvate Synthase / Q000378:metabolism*; D011817:Rabbits; D017422:Sequence Analysis, DNA; D014246:Trichomonas vaginalis / Q000201:enzymology* / Q000472:pathogenicity*
chemical_list: D008565:Membrane Proteins; D050743:Pyruvate Synthase