Scientists have developed a new strategy to enhance pharmaceutical production in Chinese hamster ovary (CHO) cells, which are commonly used to manufacture protein-based drugs for treating cancer, autoimmune diseases and much more. By knocking out a gene circuit responsible for producing lactic acid -- a metabolite that makes the cells' environment toxic -- researchers eliminate a primary hurdle in developing cells that can produce higher amounts of pharmaceuticals like Herceptin and Rituximab, without compromising their growth or energy production.