Fermentative production of lysine by Corynebacterium glutamicum: transmembrane transport and metabolic flux analysis

Since the 1950s the production of amino acids by fermentative methods has become a very important aspect of industrial microbiology, leading to numerous studies to understand and improve the metabolic conditions driving to amino acid overproduction. In this review, in addition to a brief historic background of Coryneform bacteria, the various strategies used for strain improvement, such as and the use of auxotrophic strains and regulatory mutants, are discussed. Metabolic pathways involved in the production of l-lysine by Corynebacterium glutamicum and the mechanisms mediating its efflux and secretion are discussed. Metabolic flux analysis, which is considered to be a very powerful tool providing valuable information regarding bottlenecks in the production of desired metabolites, is also covered in relation to lysine secretion in conjunction with the significance of transport mechanisms.