Historically, E. coli has been cultivated in LB Broth. Many gene expression protocols recommend this medium. LB Broth was developed in the 1950’s, nearly 20 years before the first gene was cloned and 30 years before recombinant protein expression became routine. LB Broth has proved very useful for cultivating E. coli. It was not specifically designed with the intention of maximizing the expression of recombinant proteins. LB Broth is not normally supplemented with a carbon source, nor is it buffered. Thus, the growth yields that one can obtain with LB are limited. Many proteins are not readily expressed in LB. These blends of media have proven to be the most widely applicable formulations showing consistently superior performance over the traditional medium, LB Broth. The optimum conditions for the expression of a recombinant protein requires attention to four culture-related parameters: strain employed, the medium composition, the time course of induction, and the concentration of inducing agent. Power Broth™ is a proprietary medium formulation developed by for improved expression of recombinant proteins in E. coli. This media are composed of a complex, rich mixture of amino acids, vitamins, and a carbon source at higher levels than Terrific Broth.