title: Subcellular localization of an extracellular serine protease in Leishmania (Leishmania) amazonensis.
abstract: Extracellular proteolytic activity was detected in a Leishmania ( L.) amazonensis culture supernatant and a 56-kDa protein was purified using (NH4)2SO4 precipitation followed by affinity chromatography on aprotinin-agarose. A rabbit serum obtained against the 56-kDa extracellular serine protease was used in order to analyze its location in L. ( L.) amazonensis parasites. Immunocytochemistry studies revealed that the enzyme is mainly found in the flagellar pocket and cytoplasmic vesicles of promastigote forms, whereas in amastigotes, it is located in electron-dense structures resembling megasomes. These results indicate that the 56-kDa serine protease is released into the extracellular environment through the flagellar pocket; and its intracellular location suggests either a correlated enzymatic activity or intracellular trafficking.
authors.affiliation: Laboratório de Bioquímica de Proteínas e Peptídeos, Departamento de Bioquímica e Biologia Molecular, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, RJ, Brazil. rlopez@ioc.fiocruz.br
authors.forename: R E
authors.initials: RE
authors.lastname: Silva-Lopez
authors.forename: J A
authors.initials: JA
authors.lastname: Morgado-Díaz
authors.forename: C R
authors.initials: CR
authors.lastname: Alves
authors.forename: S
authors.initials: S
authors.lastname: Côrte-Real
authors.forename: S
authors.initials: S
authors.lastname: Giovanni-De-Simone
mesh_terms: D000818:Animals; D006790:Host-Parasite Interactions; D015151:Immunoblotting; D007892:Leishmania braziliensis / Q000201:enzymology* / Q000254:growth & development / Q000648:ultrastructure; D008247:Lysosomes / Q000201:enzymology / Q000469:parasitology; D012697:Serine Endopeptidases / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D012697:Serine Endopeptidases