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Mechanisms for the methylation of As in biological systems

Mechanisms for the methylation of As in biological systems. Thiols and the reduction of As V --> As III. Organoarsenic. arsenous acid. methylarsonous acid. methylarsonic acid. dimethylarsinous acid. dimethylarsinic acid. trimethylarsinine. arsenic acid. trimethylarsenic oxide.

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Mechanisms for the methylation of As in biological systems

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  1. Mechanisms for the methylation of As in biological systems Thiols and the reduction of AsV --> AsIII

  2. Organoarsenic arsenous acid methylarsonous acid methylarsonic acid dimethylarsinous acid dimethylarsinic acid trimethylarsinine arsenic acid trimethylarsenic oxide Styblo et al, EHP 110, 5, 2002 Floreao et al, EHP 113, 6, 2005 Cullen et al, JBIC 21, 1984

  3. Electron Transfer GSH CYS Cullen et al, JBIC 21, 1984

  4. Reaction with thiols H2O MexAsO(OH)3-x + (5-x)RSH ---------> MexAs(SR)3-x + RSSR Cullen et al, JBIC 21, 1984

  5. Air oxidation of product lowers yield H2O MexAsO(OH)3-x + (5-x)RSH ---------> MexAs(SR)3-x + RSSR Cullen et al, JBIC 21, 1984

  6. Proposed Mechanism Cullen et al, JBIC 21, 1984

  7. Support for Mechanism Cullen et al, JBIC 21, 1984

  8. Steps in Reduction of AsV H2O MexAsVO(OH)3-x + (5-x)RSH ---------> MexAs(SR)3-x + RSSR Cullen et al, JBIC 21, 1984

  9. Organoarsenic arsenous acid methylarsonous acid methylarsonic acid dimethylarsinous acid dimethylarsinic acid trimethylarsinine arsenic acid trimethylarsenic oxide Styblo et al, EHP 110, 5, 2002 Floreao et al, EHP 113, 6, 2005 Cullen et al, JBIC 21, 1984

  10. Oxidative Methylation arsenous acid methylarsonous acid methylarsonic acid http://en.wikipedia.org/wiki/Rat Styblo et al, EHP 110, 5, 2002

  11. Required Cofactors arsenous acid methylarsonous acid methylarsonic acid dithiothreitol thioredoxin Styblo et al, EHP 110, 5, 2002 S-adenosyl-L-methionine

  12. In Vivo Mechanism of As methylation

  13. Biological methylation

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