The Glycolytic Enzyme Triosephosphate Isomerase of Trichomonas vaginalis Is a Surface-Associated Protein Induced by Glucose That Functions as a Laminin- and Fibronectin-Binding Protein

Autor: Arturo González-Robles, Mar Sarai Hernández-García, Rossana Arroyo, Jaime Ortega-López, Claudia G. Benítez-Cardoza, Jesús F. T. Miranda-Ozuna, Luis G. Brieba
Rok vydání: 2016
Předmět:
Zdroj: Infection and Immunity. 84:2878-2894
ISSN: 1098-5522
0019-9567
DOI: 10.1128/iai.00538-16
Popis: Triosephosphate isomerase of Trichomonas vaginalis ( Tv TIM) is a 27-kDa cytoplasmic protein encoded by two genes, tvtim1 and tvtim2 , that participates in glucose metabolism. Tv TIM is also localized to the parasite surface. Thus, the goal of this study was to identify the novel functions of the surface-associated Tv TIM in T. vaginalis and to assess the effect of glucose as an environmental factor that regulates its expression and localization. Reverse transcription-PCR (RT-PCR) showed that the tvtim genes were differentially expressed in response to glucose concentration. tvtim1 was overexpressed under glucose-restricted (GR) conditions, whereas tvtim2 was overexpressed under glucose-rich, or high-glucose (HG), conditions. Western blot and indirect immunofluorescence assays also showed that glucose positively affected the amount and surface localization of Tv TIM in T. vaginalis . Affinity ligand assays demonstrated that the recombinant Tv TIM1 and Tv TIM2 proteins bound to laminin (Lm) and fibronectin (Fn) but not to plasminogen. Moreover, higher levels of adherence to Lm and Fn were detected in parasites grown under HG conditions than in those grown under GR conditions. Furthermore, pretreatment of trichomonads with an anti- Tv TIMr polyclonal antibody or pretreatment of Lm- or Fn-coated wells with both recombinant proteins ( Tv TIM1r and Tv TIM2r) specifically reduced the binding of live parasites to Lm and Fn in a concentration-dependent manner. Moreover, T. vaginalis was exposed to different glucose concentrations during vaginal infection of women with trichomoniasis. Our data indicate that Tv TIM is a surface-associated protein under HG conditions that mediates specific binding to Lm and Fn as a novel virulence factor of T. vaginalis .
Databáze: OpenAIRE