An NAD(P)H-nicotine blue oxidoreductase is part of the nicotine regulon and may protect Arthrobacter nicotinovorans from oxidative stress during nicotine catabolism

Appl Environ Microbiol. 2007 Apr;73(8):2479-85. doi: 10.1128/AEM.02668-06. Epub 2007 Feb 9.

Abstract

An NAD(P)H-nicotine blue (quinone) oxidoreductase was discovered as a member of the nicotine catabolic pathway of Arthrobacter nicotinovorans. Transcriptional analysis and electromobility shift assays showed that the enzyme gene was expressed in a nicotine-dependent manner under the control of the transcriptional activator PmfR and thus was part of the nicotine regulon of A. nicotinovorans. The flavin mononucleotide-containing enzyme uses NADH and, with lower efficiency, NADPH to reduce, by a two-electron transfer, nicotine blue to the nicotine blue leuco form (hydroquinone). Besides nicotine blue, several other quinones were reduced by the enzyme. The NAD(P)H-nicotine blue oxidoreductase may prevent intracellular one-electron reductions of nicotine blue which may lead to semiquinone radicals and potentially toxic reactive oxygen species.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arthrobacter / enzymology
  • Arthrobacter / genetics
  • Arthrobacter / physiology*
  • Cloning, Molecular
  • Coenzymes / pharmacology
  • Electron Spin Resonance Spectroscopy
  • Flavin Mononucleotide / pharmacology
  • Gene Expression Regulation, Bacterial / physiology
  • Hydroquinones / metabolism
  • Models, Biological
  • NAD / metabolism
  • NADP / metabolism
  • Nicotine / metabolism*
  • Oxidation-Reduction
  • Oxidative Stress*
  • Quinone Reductases / genetics*
  • Quinone Reductases / isolation & purification
  • Quinone Reductases / metabolism*
  • Quinone Reductases / physiology
  • RNA, Bacterial / biosynthesis
  • RNA, Bacterial / genetics
  • RNA, Messenger / biosynthesis
  • RNA, Messenger / genetics
  • Regulon*
  • Substrate Specificity

Substances

  • Coenzymes
  • Hydroquinones
  • RNA, Bacterial
  • RNA, Messenger
  • NAD
  • NADP
  • Nicotine
  • Flavin Mononucleotide
  • Quinone Reductases
  • hydroquinone