dc.creator | MANO, Camila M. | |
dc.creator | BARROS, Marcelo P. | |
dc.creator | FARIA, Priscila A. | |
dc.creator | PRIETO, Tatiana | |
dc.creator | DYSZY, Fabio H. | |
dc.creator | NASCIMENTO, Otaciro R. | |
dc.creator | NANTES, Iseli L. | |
dc.creator | BECHARA, Etelvino J. H. | |
dc.date.accessioned | 2012-10-20T05:20:05Z | |
dc.date.accessioned | 2018-07-04T15:47:37Z | |
dc.date.available | 2012-10-20T05:20:05Z | |
dc.date.available | 2018-07-04T15:47:37Z | |
dc.date.created | 2012-10-20T05:20:05Z | |
dc.date.issued | 2009 | |
dc.identifier | FREE RADICAL BIOLOGY AND MEDICINE, v.47, n.6, p.841-849, 2009 | |
dc.identifier | 0891-5849 | |
dc.identifier | http://producao.usp.br/handle/BDPI/30818 | |
dc.identifier | 10.1016/j.freeradbiomed.2009.06.028 | |
dc.identifier | http://dx.doi.org/10.1016/j.freeradbiomed.2009.06.028 | |
dc.identifier.uri | http://repositorioslatinoamericanos.uchile.cl/handle/2250/1627457 | |
dc.description.abstract | The effects of nitrosative species on cyt c structure and peroxidase activity were investigated here in the presence of O(2)(center dot-) and anionic and zwitterionic vesicles. Nitrosative species were generated by 3-morpholinesydnonymine (SIN1) decomposition, using cyt c heme iron and/or molecular oxygen as electron acceptor. Far-and near-UV CD spectra of SIN1-treated cyt c revealed respectively a slight decrease of a-helix content (from 39 to 34%) and changes in the tryptophan structure accompanied by increased fluorescence. The Soret CD spectra displayed a significant decrease of the positive signal at 403 nm. EPR spectra revealed the presence of a low-spin cyt c form (S = 1/2) with g(1) = 2.736, g(2) = 2.465, and g(3) = 2.058 after incubation with SIN1. These data suggest that the concomitant presence of NO(center dot) and O(2)(center dot-) generated from dissolved oxygen, in a system containing cyt c and liposomes, promotes chemical and conformational modi. cations in cyt c, resulting in a hypothetical bis-histidine hexacoordinated heme iron. We also show that, paradoxically, O(2)(center dot-) prevents not only membrane lipoperoxidation by peroxide-derived radicals but also oxidation of cyt c itself due to the ability of O(2)(center dot-) to reduce heme iron. Finally, lipoperoxidation measurements showed that, although it is a more efficient peroxidase, SIN1-treated cyt c is not more effective than native cyt c in promoting damage to anionic liposomes in the presence of tert-ButylOOH, probably due to loss of affinity with negatively charged lipids. (C) 2009 Elsevier Inc. All rights reserved. | |
dc.language | eng | |
dc.publisher | ELSEVIER SCIENCE INC | |
dc.relation | Free Radical Biology and Medicine | |
dc.rights | Copyright ELSEVIER SCIENCE INC | |
dc.rights | restrictedAccess | |
dc.subject | Cytochrome c | |
dc.subject | Superoxide | |
dc.subject | Nitric oxide | |
dc.subject | Peroxynitrite | |
dc.subject | Peroxidase activity | |
dc.subject | Phosphatidylcholine | |
dc.subject | Phosphatidylglycerol | |
dc.title | Superoxide radical protects liposome-contained cytochrome c against oxidative damage promoted by peroxynitrite and free radicals | |
dc.type | Artículos de revistas | |