Metabolic Engineering of Corynebacterium Glutamicum for Biosynthesis of 5-Aminovaleric Acid

Production of bio-based polymers attracts industrial and scientific interests due to growing concerns over petroleum shortage, climate change, and human and animal health. The platform chemicals used for the synthesis of bio-polymers have been produced from renewable feedstocks using metabolically engineered strains. In particular, C5 platform chemicals such as cadaverine, 5-aminovaleric acid, and glutaric acid can be directly produced from lysine, which is readily available from a commerical fermentation process. Among these chemicals, 5-aminovaleric acid (5-AVA) is synthesized from lysine by two-step enzymatic reactions of lysine 2-monooxygenase (DavB) and delta-aminovaleramidase (DavA), and can be used for the synthesis of enineering platics such as nylon 5,6 or 5,6. In this study, we developed metabolically engineered strains of Corynebacterium glutamicum for enhanced production of 5-AVA from biosugar. The DavBA expression cassettes under the control of native or synthetic promoters with different strengths were introduced into a lysine-hyper producing C. glutamicum. The engineered C. glutamicum exhibited higher titre of 5-AVA production (10.4 g/L) than the highest value ever reported and was further evaluated in fed-batch fermentation.