title: Ecto-protein tyrosine phosphatase activity in Trypanosoma cruzi infective stages.
abstract: Live T. cruzi trypomastigotes and amastigotes possess ecto-protein tyrosine phosphatase activity as indicated by the ability of intact cells to catalyze dephosphorylation of tyrosine phosphorylated myelin basic protein, [32P]TyrRaytide, phosphotyrosine, or the phosphotyrosine analog p-nitrophenylphosphate (p-NPP). The dephosphorylation of myelin basic protein (MBP) and p-NPP was inhibited by sodium o-vanadate, zinc chloride and NaF, while dephosphorylation of [32P]TyrRaytide was insensitive to zinc chloride but sensitive to o-vanadate and NaF. In contrast, live cells were not able to dephosphorylate serine or threonine phosphorylated peptides ([32P]Kemptide) or proteins ([32P]RCM-lysozyme and [32P]MBP).
authors.affiliation: Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana 61802, USA.
authors.forename: T
authors.initials: T
authors.lastname: Furuya
authors.forename: L
authors.initials: L
authors.lastname: Zhong
authors.forename: J R
authors.initials: JR
authors.lastname: Meyer-Fernandes
authors.forename: H G
authors.initials: HG
authors.lastname: Lu
authors.forename: S N
authors.initials: SN
authors.lastname: Moreno
authors.forename: R
authors.initials: R
authors.lastname: Docampo
mesh_terms: D000818:Animals; D002384:Catalysis; D004305:Dose-Response Relationship, Drug; D006863:Hydrogen-Ion Concentration; D004676:Myelin Basic Protein / Q000378:metabolism; D009596:Nitrophenols / Q000378:metabolism / Q000494:pharmacology; D009943:Organophosphorus Compounds / Q000378:metabolism / Q000494:pharmacology; D010766:Phosphorylation; D019000:Phosphotyrosine / Q000378:metabolism / Q000494:pharmacology; D017027:Protein Tyrosine Phosphatases / Q000378:metabolism*; D014349:Trypanosoma cruzi / Q000187:drug effects / Q000201:enzymology*
chemical_list: D004676:Myelin Basic Protein; D009596:Nitrophenols; D009943:Organophosphorus Compounds; D019000:Phosphotyrosine; C008644:nitrophenylphosphate; D017027:Protein Tyrosine Phosphatases