The alterNatlve sigma factor σ54 is required for transcription of nitrogen fixation genes in
Klebsiella pneutnoniae and other diazotrophs. The nif genes, and other Eσ54‐dependent …

Expression of the nitrogen fixation (nif) genes in Klebsiella pneumoniae is tightly controlled
in response to oxygen and fixed nitrogen through a sophisticated hierarchy of regulatory …

The prokaryotic enhancer-binding protein NIFA is a multidomain transcriptional activator that
catalyzes the formation of open complexes at nitrogen fixation (nif) promoters by a …

In a wide variety of nitrogen-fixing organisms among the Purple Bacteria (large division of
Gram-negative bacteria) the nitrogen fixation (nif) operons are transcribed by an alternative …

The NIFA protein of Klebsiella pneumoniae is required for transcription of all nif (nitrogen
fixation) operons except the regulatory nifLA operon itself. NIFA activates transcription of nif …

The prokaryotic enhancer-binding protein NifA stimulates transcription at a distance by
binding to sequences upstream of nitrogen fixation (nif) promoters and catalyzing the …

The NIFA protein activates transcription of nitrogen fixation (nif) operons by the sigma 54-
holoenzyme form of RNA polymerase. We purified active NIFA from Klebsiella pneumoniae …

The interaction of the Klebsiella pneumoniae NifA protein, a σ 54-dependent activator, with
the nifE and nifU promoters was analysed. At these promoters NifA established contacts in …

The enhancer-binding protein NIFA is required for transcriptional activation of nif promoters
by the alternative holoenzyme form of RNA polymerase, which contains the sigma factor …

A model for the domain structure of σ54‐dependent transcriptional activators, based on
sequence data, has been tested by examining the function of truncated and chimaeric …