HOMEPRODUCTSSERVICESCOMPANYCONTACTFAQResearchDictionaryPharmaMobileSign Up FREE or Login

Binding of fibronectin by Trichomonas vaginalis is influenced by iron and calcium.

Abstract
We have reported that Trichomonas vaginalis, the causative agent of the most common, non-viral sexually transmitted disease, bound to cover slips coated with fibronectin (FN) (Crouch & Alderete, Microbiol 1999 145: 2835-43). In this study, we extend that observation by showing that FN binding is specific, and we present data on the requirements of FN binding by T. vaginalis. Immunofluorescence and immuno-gold labelling readily detected FN throughout the trichomonal surface. Parasites bound to(125)I-labelled FN in a time- and concentration-dependent fashion. In the absence of protease inhibitor, iodinated FN was released from the trichomonad surface. Unlabelled FN specifically competed for binding in a concentration-dependent fashion with the(125)I-labelled FN. Interestingly, the amount of FN bound by T. vaginalis organisms was dependent on iron. High-iron-grown trichomonads acquired lower numbers of molecules but with 10-fold higher affinity than low-iron-grown organisms. Further, we show that for iron-replete organisms, calcium (Ca(2+)) at physiological levels increased amounts of bound FN. The increase in binding was rapid, occurring within 5 min of Ca(2+)addition, and required de novo protein synthesis. Co-incubation of live parasites with Ca(2+)in the presence of FN was necessary to increase the amount of FN bound. Treatment of trichomonads with okadaic acid, but not other phosphatase inhibitors, resulted in a 50% decrease in binding of FN, regardless of the presence of Ca(2+), suggesting a role for phosphatase in FN association. These results indicate that depending on the iron status of T. vaginalis organisms in vivo, Ca(2+)may influence trichomonad recognition and binding to FN during host parasitism.
AuthorsM L Crouch, M Benchimol, J F Alderete
JournalMicrobial pathogenesis (Microb Pathog) Vol. 31 Issue 3 Pg. 131-44 (Sep 2001) ISSN: 0882-4010 [Print] England
PMID11500098 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)
CopyrightCopyright 2001 Academic Press.
Chemical References
  • Fibronectins
  • Protease Inhibitors
  • Okadaic Acid
  • Iron
  • Phosphoprotein Phosphatases
  • Cysteine Endopeptidases
  • Calcium
Topics
  • Animals
  • Binding, Competitive (drug effects)
  • Calcium (pharmacology)
  • Cell Adhesion (drug effects)
  • Cysteine Endopeptidases (metabolism)
  • Dose-Response Relationship, Drug
  • Female
  • Fibronectins (metabolism, pharmacology)
  • Fluorescent Antibody Technique
  • Glass
  • Humans
  • Iron (pharmacology)
  • Microscopy, Immunoelectron
  • Okadaic Acid (pharmacology)
  • Phosphoprotein Phosphatases (antagonists & inhibitors, metabolism)
  • Protease Inhibitors (pharmacology)
  • Protein Binding (drug effects)
  • Protein Biosynthesis
  • Substrate Specificity
  • Trichomonas Vaginitis (microbiology)
  • Trichomonas vaginalis (cytology, drug effects, enzymology, metabolism)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research network!


Choose Username:
Email:
Password:
Verify Password: