Formation of peroxynitrite from S-nitrosothiols and hydrogen peroxide

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Paul J. Coupe and D. Lyn H. Williams


Abstract

S-Nitrosocysteine reacts with hydrogen peroxide in aqueous buffer in the presence of EDTA to form the peroxynitrite anion. Spectral measurements show that at high pH (13.1) the peroxynitrite formed is relatively stable whereas at low pH (7.4) its decomposition rate is such that no peroxynitrite is observable. At an intermediate pH (11.6) it is possible to see both its formation and decay. Measured rate constants increase with the pH of the medium suggesting that reaction occurs by nucleophilic attack by the hydroperoxide ion at the nitroso nitrogen atom. By judicious choice of wavelength for rate measurements it is possible to obtain (in the pH range 10–13), both the second order rate constant for peroxynitrite formation and the first order rate constant for peroxynitrite decomposition. The latter is in reasonable agreement with the literature value. Other S-nitrosothiols behave similarly.


References

  1. J. S. Stamler, O. Jaraki, J. Osborne, D. I. Simon, J. Keaney, J. Vita, D. Singel, C. R. Valeri and J. Loscalzo, Proc. Natl. Acad. Sci. USA, 1992, 89, 7674 CAS.
  2. A. P. Dicks, H. R. Swift, D. L. H. Williams, A. R. Butler, H. H. Al-Sadoni and B. G. Cox, J. Chem. Soc., Perkin Trans. 2, 1996, 481 RSC.
  3. A. P. Dicks and D. L. H. Williams, Chem. Biol., 1996, 3, 655 CrossRef CAS.
  4. D. J. Barnett, A. M. Rios and D. L. H. Williams, J. Chem. Soc., Perkin Trans. 2, 1995, 1279 RSC.
  5. A. J. Holmes and D. L. H. Williams, Chem. Commun., 1998, 1711 RSC.
  6. A. P. Munro and D. L. H. Williams, unpublished work.
  7. M. N. Hughes and H. G. Nicklin, J. Chem. Soc. A, 1968, 450 RSC.
  8. T. Logager and K. Sehested, J. Phys. Chem., 1993, 97, 6664 CrossRef.
  9. J. O. Edwards and R. C. Plumb, Prog. Inorg. Chem., 1994, 41, 599 CAS.
  10. E. Halfpenny and P. L. Robinson, J. Chem. Soc., 1952, 928 RSC.
  11. J. R. Leis, M. E. Pena and A. Rios, J. Chem. Soc., Perkin Trans. 2, 1995, 587 RSC.
  12. J. S. Beckman, T. W. Beckman, J. Chen, P. A. Marshall and B. A. Freeman, Proc. Natl. Acad. Sci. USA, 1990, 87, 1620 CAS.
  13. J. M. Fukuto and L. J. Ignarro, Acc. Chem. Res., 1997, 30, 149 CrossRef CAS.
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