title: A further proteomic study on the effect of iron in the human pathogen Trichomonas vaginalis.
abstract: Iron is an essential element to support the growth and survival of Trichomonas vaginalis. It plays a critical role in the host-parasite interaction, and modulates the expression of virulence factors in this protozoan. In this work, parasites grown in iron-rich and iron-depleted media were analyzed by (i) light and scanning electron microscopy and (ii) 2-DE and MS. Withdrawal of iron from the culture medium resulted in dramatic changes in both the morphology and in the proteome pattern of T. vaginalis. Trophozoites underwent transformation from ellipsoid or amoeboid forms to rounded cells, whose flagella and axostyle were internalized. Forty-five proteins differentially expressed in parasites cultivated in the absence of iron were identified. In iron-depleted parasites, enzymes involved in energetic metabolism, proteolysis and hydrogenosomal iron-sulfur (Fe-S) proteins were down-regulated or even suppressed. Among up-regulated proteins, six isoforms of actin were detected. In addition, phosphoenolpyruvate carboxykinase, putative lactate dehydrogenase, and putative adenosine triphosphatase were also up-regulated or were exclusively observed in gels related to iron-depleted parasites. Our data demonstrate that iron has a pivotal role in the regulation of the morphological transformation of T. vaginalis and modulates the expression of both Fe-S and non-Fe-S proteins in the parasite.
authors.affiliation: Departamento de Bioquímica e Biologia Molecular, Instituto Oswaldo Cruz-FIOCRUZ, Rio de Janeiro, RJ, Brasil. jbj@ioc.fiocruz.br
authors.forename: Jose Batista
authors.initials: JB
authors.lastname: De Jesus
authors.forename: Patrícia
authors.initials: P
authors.lastname: Cuervo
authors.forename: Magno
authors.initials: M
authors.lastname: Junqueira
authors.forename: Constança
authors.initials: C
authors.lastname: Britto
authors.forename: Fernando Costa E
authors.initials: FC
authors.lastname: Silva-Filho
authors.forename: Maurílio Jose
authors.initials: MJ
authors.lastname: Soares
authors.forename: Elisa
authors.initials: E
authors.lastname: Cupolillo
authors.forename: Octavio
authors.initials: O
authors.lastname: Fernandes
authors.forename: Gilberto Barbosa
authors.initials: GB
authors.lastname: Domont
mesh_terms: D000818:Animals; D048430:Cell Shape / Q000187:drug effects / Q000502:physiology; D015180:Electrophoresis, Gel, Two-Dimensional; D005407:Flagella / Q000648:ultrastructure; D006801:Humans; D007501:Iron / Q000494:pharmacology*; D008855:Microscopy, Electron, Scanning; D020543:Proteome / Q000187:drug effects / Q000378:metabolism*; D015800:Protozoan Proteins / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013455:Sulfur / Q000494:pharmacology; D014246:Trichomonas vaginalis / Q000378:metabolism*
chemical_list: D020543:Proteome; D015800:Protozoan Proteins; D013455:Sulfur; D007501:Iron