title: Cell-associated and extracellular proteinases in Blastocrithidia culicis: influence of growth conditions.
abstract: The proteinase profile of Blastocrithidia culicis was analyzed, as well as how different growth conditions influenced its expression by gelatin-SDS-PAGE and the use of specific proteinase inhibitors. Multiple cell-associated proteinases with molecular masses corresponding to 33, 55, 60 kDa (cysteine proteinases) and 77, 80, 90, and 108 kDa (metalloproteinases) were detected using these methods. All the metalloproteinases identified were partitioned into the detergent phase after Triton X-114 extract, suggesting that they are membrane-bound, while all cysteine proteinases were partitioned into the aqueous phase. The proteolytic zymograms were similar when three different media were used for variable times of incubation. However, few quantitative and qualitative changes were observed. The secreted proteinase profile showed an heterogeneous pattern of enzymatic activities whose expression was dependent on time of growth and medium composition. However, the extracellular proteinase activities were abolished by 1,10-phenanthroline, suggesting that all of them are zinc-metalloproteinases.
authors.affiliation: Departamento de Microbiologia Geral, Instituto de Microbiologia Professor Paulo de Góes, Centro de Ciências da Saúde, Bloco I, Universidade Federal do Rio de Janeiro, Ilha do Fundão, 21941-590, Rio de Janeiro, RJ, Brazil.
authors.forename: A L
authors.initials: AL
authors.lastname: dos Santos
authors.forename: C M
authors.initials: CM
authors.lastname: Abreu
authors.forename: L M
authors.initials: LM
authors.lastname: Batista
authors.forename: C S
authors.initials: CS
authors.lastname: Alviano
authors.forename: R M
authors.initials: RM
authors.lastname: de Araújo Soares
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000201:enzymology; D003470:Culture Media; D003546:Cysteine Endopeptidases / Q000737:chemistry / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D008666:Metalloendopeptidases / Q000737:chemistry / Q000378:metabolism*; D008970:Molecular Weight; D010618:Phenanthrolines / Q000494:pharmacology; D011480:Protease Inhibitors / Q000494:pharmacology; D014351:Trypanosomatina / Q000201:enzymology* / Q000254:growth & development
chemical_list: D003470:Culture Media; D010618:Phenanthrolines; D011480:Protease Inhibitors; D003546:Cysteine Endopeptidases; D008666:Metalloendopeptidases; C025205:1,10-phenanthroline