Reactions of nitric oxide and oxygen with the regulator of fumarate and nitrate reduction, a global transcriptional regulator, during anaerobic growth of Escherichia coli

Methods Enzymol. 2008:437:191-209. doi: 10.1016/S0076-6879(07)37011-0.

Abstract

The Escherichia coli fumarate and nitrate reductase (FNR) regulator protein is an important transcriptional regulator that controls the expression of a large regulon of more than 100 genes in response to changes in oxygen availability. FNR is active when it acquires a [4Fe-4S](2+) cluster under anaerobic conditions. The presence of the [4Fe-4S](2+) cluster promotes protein dimerization and site-specific DNA binding, facilitating activation or repression of target promoters. Oxygen is sensed by the controlled disassembly of the [4Fe-4S](2+) cluster, ultimately resulting in inactive, monomeric, apo-FNR. The FNR [4Fe-4S](2+) cluster is also sensitive to nitric oxide, such that under anaerobic conditions the protein is inactivated by nitrosylation of the iron-sulfur cluster, yielding a mixture of monomeric and dimeric dinitrosyl-iron cysteine species. This chapter describes some of the methods used to produce active [4Fe-4S] FNR protein and investigates the reaction of the [4Fe-4S](2+) cluster with nitric oxide and oxygen in vitro.

Publication types

  • Review

MeSH terms

  • Acids / pharmacology
  • Anaerobiosis / genetics
  • Escherichia coli / enzymology*
  • Escherichia coli / genetics
  • Escherichia coli / growth & development*
  • Escherichia coli / metabolism
  • Escherichia coli Proteins / chemistry
  • Escherichia coli Proteins / isolation & purification
  • Escherichia coli Proteins / metabolism*
  • Escherichia coli Proteins / physiology
  • Fumarates / metabolism*
  • Gene Expression Regulation, Bacterial
  • Iron / metabolism
  • Iron-Sulfur Proteins / chemistry
  • Iron-Sulfur Proteins / isolation & purification
  • Iron-Sulfur Proteins / metabolism*
  • Iron-Sulfur Proteins / physiology
  • Nitrates / metabolism*
  • Nitric Oxide / metabolism*
  • Oxidation-Reduction
  • Oxygen / metabolism*
  • Peroxides / analysis
  • Recombinant Proteins / isolation & purification
  • Spectrophotometry, Ultraviolet
  • Sulfides / metabolism
  • Superoxides / analysis
  • Transcription, Genetic

Substances

  • Acids
  • Escherichia coli Proteins
  • FNR protein, E coli
  • Fumarates
  • Iron-Sulfur Proteins
  • Nitrates
  • Peroxides
  • Recombinant Proteins
  • Sulfides
  • Superoxides
  • ferryl iron
  • Nitric Oxide
  • Iron
  • Oxygen