Learning new tricks from an old dog -: MaIT of the Escherichia coli maltose system is part of a complex regulatory network

The regulation of the maltose system in Escherichia coli has traditionally been viewed as a simple positive feedback loop. Today, we know that there are cross connections to several, seemingly unrelated, metabolic pathways. MalT, the central activator of the mal genes, is the key element in this complex regluatory network and integrates the different signals to give an appropriate transcriptional response.