The peroxynitrite/porphyrin biomimetic system was established to investigate the effects of peroxynitrite on benzo[a]pyrene (B[a]P) metabolism. Three model systems consisting of different iron porphyrins were compared, and the results showed that the peroxynitrite/T(p-Cl)PPFeCl system was the highest catalytic efficiency in the metabolism of B[a]P. We analyzed the B[a]P metabolites produced from this system by RP-HPLC method and firstly identified the formation of nitrobenzo[a]pyrenes which are the special metabolites of B[a]P induced by peroxynitrite.
LUO Yun-jing LIN Tai-feng ZHANG Shu-fen LIU Rui ZHONG Ru-gang
NO· and ·O2-combine each other to form peroxynitrite (ONOO-) in vivo. Peroxynitrite is very cytotoxic, and it damages many biomolecules. 3-nitrotyrosine and dityrosine are two main products from the reaction of ONOO-and tyrosine. Lots of metallic ions in vivo influence the modification of tyrosine by peroxynitrite. UV-Vis and Fluorescence spectrophotometer were used to study the catalysis and inhibition of metallic ions on the production of 3-nitrotyrosine and dityrosine in vitro. Present results showed that Co?髤, Cu?髤 and Mn?髤 enhance the production of 3-nitrotyrosine, and among them Co?髤 and Mn?髤 have been reported rarely before about it. In addition, Mn?髤 inhibits the production of dityrosine to a certain extent.
