Reciprocal regulation of the lrpA1 and the aspB3 gene expression. LrpA1 binds together with aspartate to the aspB3 promoter in order to prevent aspB3 gene expression (A). Once aspartate is metabolized in the medium LrpA1 no longer has the ability to bind to the aspB3 promoter. Instead, aspB3 gene expression will be activated to generate aspartate from glutamate. Without aspartate LrpA1 binds to the lrpA1 promoter to repress lrpA1 gene expression (B).
Schwaiger et al. BMC Molecular Biology 2010 11:40 doi:10.1186/1471-2199-11-40