A nitric oxide synthase was partially purified from soluble extracts of Trypanosoma cruzi epimastigote forms. The conversion of L-arginine to citrulline by this enzyme activity required NADPH and was blocked by EGT(A). The reaction was activated by Ca2+, calmodulin, tetrahydrobiopterin, and FAD, and inhibited by N(ω)-methyl-L-arginine. L-Glutamate and N-methyl-D- aspartate stimulated in vivo conversion of L-arginine to citrulline by epimastigote cells. These stimulations could be blocked by EGTA, MK-801, and ketamine and enhanced by glycine. A sodium nitroprusside-activated guanylyl cyclase activity was detected in cell-free, soluble preparations of T. cruzi epimastigotes. L-Glutamate, N-methyl-D-aspartate, and sodium nitroprusside increased epimastigote cyclic GMP levels. MK-801 bound specifically to T. cruzi epimastigote cells. This binding was competed by ketamine and enhanced by glycine or L-serine. Evidence thus indicates that in T. cruzi epimastigotes, L-glutamate controls cyclic GMP levels through a pathway mediated by nitric oxide.
Documento: | Artículo |
Título: | The nitric oxide transduction pathway in Trypanosoma cruzi |
Autor: | Paveto, C.; Pereira, C.; Espinosa, J.; Montagna, A.E.; Farber, M.; Esteva, M.; Flawia, M.M.; Torres, H.N. |
Filiación: | INGEBI, Obligado 2490, Buenos Aires 1428, Argentina |
Palabras clave: | 2 amino 5 phosphonovaleric acid; amino acid derivative; arginine; calcium; calmodulin; citrulline; cyclic gmp; dizocilpine; egtazic acid; flavine adenine nucleotide; glutamic acid; glycine; guanylate cyclase; ketamine; n methyl dextro aspartic acid; n(g) methylarginine; nitric oxide; nitric oxide synthase; nitroprusside sodium; reduced nicotinamide adenine dinucleotide phosphate; serine; tetrahydrobiopterin; article; cell free system; controlled study; enzyme activity; epimastigote; nonhuman; priority journal; receptor binding; signal transduction; trypanosoma cruzi; Amino Acid Oxidoreductases; Animal; Arginine; Citrulline; Cyclic GMP; Dizocilpine Maleate; Guanylate Cyclase; Nitric Oxide; Nitric-Oxide Synthase; Receptors, N-Methyl-D-Aspartate; Support, Non-U.S. Gov't; Trypanosoma cruzi |
Año: | 1995 |
Volumen: | 270 |
Número: | 28 |
Página de inicio: | 16576 |
Página de fin: | 16579 |
DOI: | http://dx.doi.org/10.1074/jbc.270.28.16576 |
Título revista: | Journal of Biological Chemistry |
Título revista abreviado: | J. BIOL. CHEM. |
ISSN: | 00219258 |
CODEN: | JBCHA |
CAS: | 2 amino 5 phosphonovaleric acid, 76726-92-6; arginine, 1119-34-2, 15595-35-4, 7004-12-8, 74-79-3; calcium, 7440-70-2; citrulline, 372-75-8; cyclic GMP, 7665-99-8; dizocilpine, 77086-21-6; egtazic acid, 67-42-5; flavine adenine nucleotide, 146-14-5; glutamic acid, 11070-68-1, 138-15-8, 56-86-0, 6899-05-4; glycine, 56-40-6, 6000-43-7, 6000-44-8; guanylate cyclase, 9054-75-5; ketamine, 1867-66-9, 6740-88-1, 81771-21-3; n methyl dextro aspartic acid, 6384-92-5; n(g) methylarginine, 156706-47-7, 17035-90-4; nitric oxide synthase, 125978-95-2; nitric oxide, 10102-43-9; nitroprusside sodium, 14402-89-2, 15078-28-1; reduced nicotinamide adenine dinucleotide phosphate, 53-57-6; serine, 56-45-1, 6898-95-9; tetrahydrobiopterin, 17528-72-2; Amino Acid Oxidoreductases, EC 1.4.; Arginine, 74-79-3; Citrulline, 372-75-8; Cyclic GMP, 7665-99-8; Dizocilpine Maleate, 77086-22-7; Guanylate Cyclase, EC 4.6.1.2; Nitric Oxide, 10102-43-9; Nitric-Oxide Synthase, EC 1.14.13.39; Receptors, N-Methyl-D-Aspartate |
Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00219258_v270_n28_p16576_Paveto |