Systems Metabolic Engineering of Escherichia coli for the Efficient Production of Putrescine: A Four Carbon Diamine

Putrescine, also known as 1,4-diaminobutane, is an important nitrogen-containing platform chemical with numerous applications in industry. Particularly, putrescine is currently polycondensed with adipic acid to synthesize nylon-4,6 (Stanyl®, DSM), a superior engineering plastic because of its high melting point and mechanical strength as well as excellent solvent resistance. Current production of putrescine on industrial scale relies mainly on chemical synthesis from petrochemicals under harsh conditions. From an environmental point of view, the chemical synthesis route is undesirable.Here we show a sustainable bio-based process for putrescine production using metabolically engineered strain of Escherichia coli. The final engineered E. coli strain was able to produce 1.68 g L-1 of putrescine with a yield of 0.168 g per g glucose in a batch cultivation. Furthermore, high cell density cultivation allowed production of 24.2 g L-1 of putrescine within 32 hour. The strategy reported here should be useful for the bio-based production of putrescine from renewable resources, and also for the development of strains capable of producing other diamines, which are important as nitrogen-containing platform chemicals. [This work was supported by the Korean Systems Biology Research Project (20100002164) of the Ministry of Education, Science and Technology (MEST) through the National Research Foundation of Korea. Further support by the World Class University Program (R32-2008-000-10142-0) through the National Research Foundation of Korea funded by the MEST is appreciated.]