DNA-binding protein involved in the repression of transcription of a large number of genes, thereby arresting growth, in response to environmental changes (PubMed:14976242, PubMed:18073105). Binding sites are identified in promoters of approximately 200 transcription units, including genes involved in ATP synthesis, transmembrane transport, translation and DNA synthesis (PubMed:18073105). In the famine mode, FL11 forms dimers and acts as a repressor, leading to growth arrest (PubMed:18073105). In the feast mode, in the presence of high concentrations of lysine or arginine, four dimers assemble into an octamer and cover the fl11 and lysine biosynthesis promoters (PubMed:18073105, PubMed:19004003). This leads to the inhibition of fl11 expression and lysine biosynthesis, decrease of the FL11 concentration in the cell, derepression of the target genes and activation of the metabolism (PubMed:18073105). Homodimer (PubMed:14976242, PubMed:18073105, PubMed:19004003). Binds DNA as a dimer and an octamer (PubMed:18073105, PubMed:19004003). The octamer formed with lysine is stable in solution, but the octamer formed with arginine is unstable without DNA (PubMed:19004003). When crystallized in the absence of DNA, dimers are assembled into helical cylinders with six dimers per turn (PubMed:14976242). In solution, predominantly behaves as a dimer (PubMed:14976242).