Leishmania mexicana promastigotes secrete a protein tyrosine phosphatase

• Published in: Parasitology research (1987) 2010-07, Vol.107 (2), p.309-315
• Main Authors: Escalona-Montaño, Alma R, Pardavé-Alejandre, Daniel, Cervantes-Sarabia, Rocely, García-López, Patricia, Gutiérrez-Quiroz, Manuel, Gutiérrez-Kobeh, Laila, Becker-Fauser, Ingeborg, Aguirre-García, Maria M
• Format: Article
• Language: English
• Subjects: Antibodies; Antibodies, Monoclonal - immunology; Antibodies, Protozoan - immunology; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; Cell culture; Culture Media - chemistry; Dendritic cells; Dephosphorylation; Enzymatic activity; Fundamental and applied biological sciences. Psychology; General aspects; General aspects and techniques. Study of several systematic groups. Models; Immunology; Invertebrates; Leishmania major; Leishmania mexicana; Leishmania mexicana - enzymology; Macrophages; Medical Microbiology; Microbiology; Microorganisms; Monoclonal antibodies; Original Paper; Pathogenicity; Phosphorylation; Placenta; Promastigotes; Protein Tyrosine Phosphatases - immunology; Protein Tyrosine Phosphatases - secretion; Protein-tyrosine kinase; Protein-tyrosine-phosphatase; Protozoan Proteins - immunology; Protozoan Proteins - secretion; Serine; Threonine; Trypanosoma brucei; Virulence Factors - immunology; Virulence Factors - metabolism
• ISSN: 0932-0113; 1432-1955
• DOI: 10.1007/s00436-010-1863-5

Leishmania mexicana is an intracellular protozoan parasite that infects macrophages and dendritic cells and causes a chronic cutaneous disease. Although many enzymatic activities have been reported in this parasite, the presence of kinases and phosphatases has been poorly studied. These enzymes control the phosphorylation and dephosphorylation of proteins. Specifically, protein tyrosine kinases phosphorylate tyrosine residues and protein tyrosine phosphatases (PTPases) dephosphorylate tyrosine residues. PTPase activities have been reported as pathogenic factors in various infectious microorganisms such as viruses, bacteria, and parasites. Also, it has been shown that the induction of one or more PTPase activities in macrophages represents an important pathogenicity factor in Leishmania. Recently, we reported a membrane-bound PTPase activity in promastigotes of Leishmania major. In the present work, we give evidence that promastigotes of L. mexicana are able to secrete a PTPase into the culture medium. Two antibodies: one monoclonal against the catalytic domains of the human placental PTPase 1B and a polyclonal rabbit anti-recombinant protein Petase7 from Trypanosoma brucei cross-reacted with a 50-kDa molecule. The anti-human PTPase 1B antibody depleted the enzymatic activity present in the conditioned medium. The pattern of sensitivity and resistance to specific PTPase and serine/threonine inhibitors showed that this enzyme is a protein tyrosine phosphatase.