Heterogeneity in extracellular nucleotide hydrolysis among clinical isolates of Trichomonas vaginalis

Trichomonas vaginalis is a parasitic protozoan that causes trichomonosis, a sexually-transmitted disease, with serious sequelae to women and men. As the host–parasite relationship is complex, it is important to investigate biochemical aspects of the parasite that contribute to our understanding of t...

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Detalles Bibliográficos
Autores: Tasca, Tiana, Bonan, Carla Denise, De Carli, Geraldo Attilio, Sarkis, João José Freitas, Alderete, John Fernando
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2005
País:Brasil
Institución:Universidade Federal do Rio Grande do Sul (UFRGS)
Repositorio:Repositório Institucional da UFRGS
Idioma:inglés
OAI Identifier:oai:www.lume.ufrgs.br:10183/27459
Acceso en línea:http://hdl.handle.net/10183/27459
Access Level:acceso abierto
Palabra clave:Hidrólise
Trichomonas vaginalis
Bioquímica
Nucleoside triphosphate diphosphohydrolase
Ecto-5k-nucleotidase
Fresh isolates
Heterogeneity
Descripción
Sumario:Trichomonas vaginalis is a parasitic protozoan that causes trichomonosis, a sexually-transmitted disease, with serious sequelae to women and men. As the host–parasite relationship is complex, it is important to investigate biochemical aspects of the parasite that contribute to our understanding of trichomonal biology and pathogenesis. Nucleoside triphosphate diphosphohydrolase 1 (NTPDase 1), which hydrolyses extracellular ATP and ADP, and ecto-5k-nucleotidase, which hyrolyses AMP, have been characterized in laboratory isolates of T. vaginalis. Here we show that the extracellular ATP:ADP hydrolysis ratio varies among fresh clinical isolates, which presented higher ATPase and ADPase activities than long-term-grown isolates. Growth of parasites in iron-replete and iron-depleted medium resulted in different, albeit minor, patterns in extracellular ATP and ADP hydrolysis among isolates. Importantly, some isolates had low or absent ecto-5k-nucleotidase activity, regardless of environmental conditions tested. For isolates with ecto-5k-nucleotidase activity, high- and low-iron trichomonads had increased and decreased levels of activity, respectively, compared to organisms grown in normal TYM-serum medium. This suggests a regulation in expression of either the enzyme amounts and/or activity under the control of iron. Finally, we found no correlation between the presence or absence of dsRNA virus infection among trichomonad isolates and NTPDase and ecto-5k-nucleotidase activities.