To grow and multiply efficiently, bacteria must coordinate cell division with chromosome segregation. Key to this process is a protein called Nucleoid Occlusion Factor or Noc. A small and abundant molecule called Cytidine Triphosphate (CTP) is key to the functions of Noc. CTP binding enables Noc to "spread" on DNA to form a large protein complex. CTP also "switches on" the membrane-binding ability of Noc.