Copper is an essential trace metal for both prokaryotes and eukaryotes, and is associated with various metal enzymes which play many essential roles in the living system. But excess of the metal is very toxic and even lethal for living organisms. In microorganisms the intracellular level of copper is maintained by many genes working as an operon and induced by the presence of copper in their environment. One such operon is called cus operon regulated by cusRS two component system in Klebsiella pneumoniae. This cusS (sensory region) and cusR (regulatory region) autoregulate the expression of...