Biosynthesis of Valerolactam by Synechococcus elongatus UTEX 2973
We are doing a two year project!
Lactams are family of cyclic amides widely used in the synthesis materials including nylon and piperidines used in drugs. Traditionally, lactams are synthesized through energy-intensive petrochemical methods. Here, we describe a method using Synechococcus elongatus UTEX 2973 as a chassis for the production of δ-valerolactam. A feedback insensitive aspartate kinase (AK) is used to achieve overproduction of lysine. Lysine is then oxidized to δ-amino-valeramide by L-Lysine monooxygenase (DavB), which is further hydrolyzed to δ-aminovalerate (5-AVA) by 5-aminovaleramide amidohydrolase (DavA). The resulting 5-AVA is cyclized to form δ-valerolactam. A shuttle vector with the feedback insensitive AK, davB and davA is integrated to S.elongatus UTEX 2973 through the INTEGRATE system, a previously described CRISPR-transposon system. Since reported cyclases for the cyclization of 5-AVA to δ-valerolactam are not efficient, an efficient cyclase is also designed using computational analysis.