Intergenic region between nifA and pnfA and construction of the pnfA non-polar mutant A1325. The open and filled boxes represent the putative σ54-dependent promoter and upstream activator sequences, respectively. The inverted triangle indicates the location of the mutations inserted into pnfA via homologous suicide plasmid integration.
Yan et al. BMC Genomics 2010 11:11 doi:10.1186/1471-2164-11-11