The FNR Modulon and FNR-Regulated Gene Expression

  • John R. Guest
  • Jeffrey Green
  • Alistair S. Irvine
  • Stephen Spiro


In recent years it has been realized that the elaborate network of interacting metabolic processes operating in living bacteria is not maintained simply by controlling enzyme activities in response to specific metabolites (substrates, end-products and allosteric effectors) or by controlling enzyme synthesis via specific regulatory proteins that activate or repress relevant transcriptional units (genes, operons or regulons) in response to the corresponding metabolites (coeffectors). There is yet another tier of complexity imposed by global regulators which control families of transcriptional units in response to general metabolic or environmental factors. These families have been called regulatory networks or modulons. By belonging to one or more such modulons, the pattern of gene expression can be adapted to that required for a specific metabolic mode or physiological state. A major current challenge is to understand how multiple regulatory factors exert their various effects on a single transcriptional unit, and whether such interactions are sufficient to establish and maintain the complex coordinated metabolic networks operating under diverse physiological conditions, or whether other factors such as the regulation of regulatory gene expression, make a significant contribution to the overall process.


Aerobic Respiration Anaerobic Respiration Sensory Domain Fumarate Reductase Nitrate Respiration 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© R.G. Landes Company 1996

Authors and Affiliations

  • John R. Guest
  • Jeffrey Green
  • Alistair S. Irvine
  • Stephen Spiro

There are no affiliations available

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