An ecto-protein tyrosine phosphatase of Entamoeba histolytica induces cellular detachment by disruption of actin filaments in HeLa cells

• Published in: International journal for parasitology 2003-07, Vol.33 (7), p.663-670
• Main Authors: Anaya-Ruiz, M., Pérez-Santos, J.L.M., Talamás-Rohana, P.
• Format: Article
• Language: English
• Subjects: Actin Cytoskeleton - ultrastructure; Actin disruption; Animals; Antibodies, Monoclonal - metabolism; Biological and medical sciences; Cell Death; Cell detachment; Entamoeba histolytica; Entamoeba histolytica - enzymology; Entamoeba histolytica - pathogenicity; Fundamental and applied biological sciences. Psychology; HeLa Cells - parasitology; HeLa Cells - ultrastructure; Host-Parasite Interactions; Humans; Life cycle. Host-agent relationship. Pathogenesis; Placenta - enzymology; Precipitin Tests - methods; Protein Tyrosine Phosphatases - immunology; Protein Tyrosine Phosphatases - isolation & purification; Protein Tyrosine Phosphatases - metabolism; Protozoa; Protozoan Proteins - isolation & purification; Protozoan Proteins - metabolism; PTPase; Secreted acid phosphatase
• ISSN: 0020-7519; 1879-0135
• DOI: 10.1016/S0020-7519(03)00029-8

Actin cytoskeleton disruption in host cells has been demonstrated for PTPases from pathogenic microorganisms. In this work, we analysed whether the secreted acid phosphatase from Entamoeba histolytica has phosphotyrosine phosphatase activity and the possibility that this activity may participate in damaging host cells. The secreted acid phosphatase of E. histolytica, which catalyses p-nitrophenyl phosphate hydrolysis at acid pH values, was found to have phosphotyrosine phosphatase activity. The enzymatic properties of phosphotyrosine phosphatase and acid phosphatase were virtually identical and included: K m values of 10×10 −4 M, no requirement for divalent cations, and sensitivity to molybdate, vanadate, and tungstate. The phosphotyrosyl phosphatase activity caused significant levels of cell rounding and detachment correlating with disruption of the actin stress fibres in HeLa cells. Thus, our data suggest that secreted phosphotyrosine phosphatase could play a cytotoxic role during amoebic infection.