Glutamine substitution: the role it can play to enhance therapeutic protein production

Abstract

The biopharmaceutical market is driven by the steady increase in demand for therapeutic proteins produced in mammalian cells. Glutamine is a main nitrogen source and also a main energy source with glucose in mammalian cell cultures for therapeutic protein production. As a result of glutamine metabolism and the natural decomposition of glutamine, ammonia, which is known to negatively affect cell growth, protein production and sialylation of recombinant glycoprotein, is necessarily accumulated in a culture medium. This review highlights the current strategies and achievements in overcoming the negative effect of ammonia through the glutamine substitution by less ammoniagenic substrates, such as glutamate, pyruvate and a-ketoglutarate.