Cloning Defined Regions of the pExo Megaplasmid of Rhizobium (Sinorhizobium) Meliloti

Bacteria that form nitrogen-fixing nodules on the roots of plants have been the subject of much research over the past twenty years. This has led to major breakthroughs in understanding how bacteria interact with plants and fix nitrogen. The model system most extensively studied is the interaction between the bacterium Rhizobium meliloti and alfalfa. The R. meliloti genome consists of three replicons, a chromosome of 3540 Kb and two …