The increasing worldwide demand for energy, combined with diminishing fossil fuel reserves and concerns about climate change, have stimulated intense research into the development of renewable energy sources, in particular, microbial biofuels. For a biofuel to be commercially viable, the production processes, yield, and titer have to be optimized, which can be achieved through the use of microbial cell factories. Using multidisciplinary research approaches, and through the application of diverse biotechnologies (such as enzyme engineering, metabolic engineering, systems biology, and synthetic...