Gp63-like molecules in Phytomonas serpens: possible role in the insect interaction.
In this study, we demonstrated that metallopeptidase inhibitors (EDTA, EGTA, and 1,10-phenanthroline) were able to arrest Phytomonas serpens growth in distinct patterns. This parasite released exclusively metallopeptidases to the extracellular environment, whereas in cellular extracts only cysteine peptidases were detected. In addition, an extracellular polypeptide of 60 kDa reacted in Western blotting probed with polyclonal antibody raised against gp63 of Leishmania amazonensis. In the cellular parasite extract, this antibody recognized bands migrating at 63 and 52 kDa, which partitioned on both aqueous and membrane-rich fractions. Flow cytometry and fluorescence microscopy analyses showed that the gp63-like molecules have a surface location. Moreover, phospholipase C (PLC)-treated parasites reduced the number of gp63-positive cells. The anti-cross-reacting determinant (CRD) and anti-gp63 antibodies recognized the 60-kDa band in the supernatant from PLC-treated cells, suggesting that this protein is glycosylphosphatidylinositol-anchored to the plasma membrane. This is the first report on the presence of gp63-like molecules in members of the Phytomonas genus. The pretreatment of the parasites with anti-gp63 antibody significantly diminished their adhesion index to explanted salivary glands of the phytophagous insect Oncopeltus fasciatus, suggesting a potential involvement of the gp63-like molecules in the adhesive process of this plant trypanosomatid.
d'Avila-Levy
Claudia M
CM
Departamento de Microbiologia Geral, Instituto de Microbiologia Prof. Paulo de Góes, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Ilha do Fundão, Rio de Janeiro, RJ, 21941-590, Brazil.
Santos
Lívia O
LO
Marinho
Fernanda A
FA
Dias
Felipe A
FA
Lopes
Angela H
AH
Santos
André L S
AL
Branquinha
Marta H
MH
D000818:Animals; D020062:Heteroptera / Q000469:parasitology*; D006790:Host-Parasite Interactions / Q000502:physiology; D007303:Insect Vectors / Q000502:physiology; D008666:Metalloendopeptidases / Q000032:analysis / Q000276:immunology; D045726:Metalloproteases / Q000378:metabolism; D015800:Protozoan Proteins / Q000502:physiology*; D014345:Trypanosoma / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*
D015800:Protozoan Proteins; D045726:Metalloproteases; D008666:Metalloendopeptidases; C055146:glycoprotein gp63, Leishmania