Nitric oxide biosynthesis by Leishmania amazonensis promastigotes containing a high percentage of metacyclic forms.
Due to the diversity of its physiological and pathophysiological functions and general ubiquity, the study of nitric oxide (NO) has become of great interest. In this work, it was demonstrated that Leishmania amazonensis promastigotes produces NO, a free radical synthesized from L: -arginine by nitric oxide synthase (NOS). A soluble NOS was purified from L. amazonensis promastigotes by affinity chromatography (2', 5'-ADP-agarose) and on SDS-PAGE the enzyme migrates as a single protein band of 116.2 (+/-6) kDa. Furthermore, the presence of a constitutive NOS was detected through indirect immunofluorescence using anti-cNOS and in NADPH consumption assays. The present work show that NO production, detected as nitrite in culture supernatant, is prominent in promastigotes preparations with high number of metacyclic forms, suggesting an association with the differentiation and the infectivity of the parasite.
Department of Immunology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation - FIOCRUZ, Rio de Janeiro, Brazil. genestra@ioc.fiocruz.br
Marcelo
M
Genestra
Wilson J S
WJ
Souza
Damiana
D
Guedes-Silva
Gérzia M C
GM
Machado
Léa
L
Cysne-Finkelstein
Rômulo José Soares
RJ
Bezerra
Fabiane
F
Monteiro
Leonor L
LL
Leon
D000818:Animals; D002846:Chromatography, Affinity; D004591:Electrophoresis, Polyacrylamide Gel; D007894:Leishmania mexicana / Q000737:chemistry / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D008970:Molecular Weight; D009249:NADP / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000302:isolation & purification* / Q000378:metabolism
D009569:Nitric Oxide; D009249:NADP; D019001:Nitric Oxide Synthase