title: Trichomonas vaginalis: identification of soluble and membrane-associated phospholipase A1 and A2 activities with direct and indirect hemolytic effects.
abstract: A direct hemolytic activity, dependent on phospholipase A (PLA) activity, was located in the particulate subcellular fraction (P30) of Trichomonas vaginalis. We identified soluble direct and indirect hemolytic activities in the spent medium and soluble fraction (S30) of T. vaginalis strain GT-13. Spent medium showed the highest specific indirect hemolytic activity (SIHA) at pH 6.0 (91 indirect hemolytic units [HU]/mg/hr). Spent medium and P30, but not S30, showed direct hemolytic activity. PLA activity was protein dose dependent and time dependent. The highest PLA activity was observed at pH 6.0. All trichomonad preparations showed phospholipase A1 (PLA A1) and phospholipase A2 (PLA A2) activities. Indirect and direct hemolytic activity and PLA A1 and PLA A2 diminished at pH 6.0 and 8.0 with increasing concentrations of Rosenthal's inhibitor. The greatest effect was observed with 80 microM at pH 6.0 on the SIHA of S30 (83% reduction) and the lowest at pH 8.0, also on the SIHA of S30 (26% reduction). In conclusion, T. vaginalis contains particulate and soluble acidic, and alkaline direct and indirect hemolytic activities, which are partially dependent on alkaline or acidic PLA A1 and PLA A2 enzymes. These could be responsible for the contact-dependent and -independent hemolytic and cytolytic activities of T. vaginalis.
authors.affiliation: División de Biología Celular y Molecular, Centro de Investigacíon Biomédica del Noreste, Instituto Mexicano del Seguro Social, Administración de correo No. 4, Apartado postal 020-E, Colonia Independencia, Monterrey, CP 64720, Nuevo León, México.
authors.forename: Javier
authors.initials: J
authors.lastname: Vargas-Villarreal
authors.forename: Benito David
authors.initials: BD
authors.lastname: Mata-Cárdenas
authors.forename: Rebeca
authors.initials: R
authors.lastname: Palacios-Corona
authors.forename: Francisco
authors.initials: F
authors.lastname: González-Salazar
authors.forename: Elva I
authors.initials: EI
authors.lastname: Cortes-Gutierrez
authors.forename: Herminia G
authors.initials: HG
authors.lastname: Martínez-Rodríguez
authors.forename: Salvador
authors.initials: S
authors.lastname: Said-Fernández
mesh_terms: D000818:Animals; D017077:Culture Media, Conditioned / Q000494:pharmacology; D005260:Female; D006461:Hemolysis / Q000187:drug effects / Q000502:physiology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010741:Phospholipases A / Q000037:antagonists & inhibitors / Q000378:metabolism*; D054466:Phospholipases A1; D054467:Phospholipases A2; D013228:Stearates / Q000494:pharmacology; D014246:Trichomonas vaginalis / Q000201:enzymology*
chemical_list: D017077:Culture Media, Conditioned; D013228:Stearates; C015161:Rosenthal's inhibitor; D010741:Phospholipases A; D054466:Phospholipases A1; D054467:Phospholipases A2