Genestra Marcelo, Souza Wilson J S, Guedes-Silva Damiana, Machado Gérzia M C, Cysne-Finkelstein Léa, Bezerra Rômulo José Soares, Monteiro Fabiane, Leon Leonor L
Department of Immunology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation - FIOCRUZ, Rio de Janeiro, Brazil.
Arch Microbiol. 2006 Jun;185(5):348-54. doi: 10.1007/s00203-006-0105-9. Epub 2006 Mar 31.
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.
由于一氧化氮（NO）具有多样的生理和病理生理功能且普遍存在，对其的研究已引起了极大的兴趣。在这项工作中，已证明亚马逊利什曼原虫前鞭毛体能产生NO，它是一种由一氧化氮合酶（NOS）从L-精氨酸合成的自由基。通过亲和层析（2',5'-ADP-琼脂糖）从亚马逊利什曼原虫前鞭毛体中纯化出一种可溶性NOS，在SDS-PAGE上该酶迁移为一条116.2（±6）kDa的单一蛋白带。此外，通过使用抗cNOS的间接免疫荧光和NADPH消耗试验检测到了组成型NOS的存在。目前的工作表明，在培养上清液中检测为亚硝酸盐的NO产生，在具有大量成熟循环型的前鞭毛体制剂中很突出，这表明与寄生虫的分化和感染性有关。
