Two-electron reduction of nitroaromatic compounds by Enterobacter cloacae NAD(P)H nitroreductase: Description of quantitative structure-activity relationships

Henrikas Nivinskas, Ronald L. Koder, Žilvinas Anusevičius, Jonas Šarlauskas, Anne Frances Miller, Narimantas Čenas

Research output: Contribution to journalArticlepeer-review

18 Scopus citations

Abstract

Enterobacter cloacae NAD(P)H: nitroreductase catalyzes the reduction of a series of nitroaromatic compounds with steady-state bimolecular rate constants (kcat/Km) ranging from 104 M-1s-1 to 107 M-1s-1, and oxidizing 2 moles NADH per mole mononitrocompound. Oxidation of excess NADH by polynitrobenzenes including explosives 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitrophenyl-N-methylnitramine (tetryl), has been observed as a slower secondary process, accompanied by O2 consumption. This type of 'redox cycling' was not related to reactions of nitroaromatic anion-radicals, but was caused by the autoxidation of relatively stable reaction products. The logs kcat/Km of all the compounds examined exhibited parabolic dependence on their enthalpies of single-electron- or two-electron (hydride) reduction, obtained by quantum mechanical calculations. This type of quantitative structure-activity relationships shows that the reactivity of nitroaromatics towards E. cloacae nitroreductase depends mainly on their hydride accepting properties, but not on their particular structure, and does not exclude the possibility of multistep hydride transfer.

Original languageEnglish
Pages (from-to)941-949
Number of pages9
JournalActa Biochimica Polonica
Volume47
Issue number4
DOIs
StatePublished - 2000

Keywords

  • Electron transfer
  • Explosive
  • HMX
  • Nitroreductase
  • Pentryl
  • RDX
  • TNT
  • Tetryl

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology (all)

Fingerprint

Dive into the research topics of 'Two-electron reduction of nitroaromatic compounds by Enterobacter cloacae NAD(P)H nitroreductase: Description of quantitative structure-activity relationships'. Together they form a unique fingerprint.

Cite this