Design and Assembly of a Biofactory for (2 S )-Naringenin Production in Escherichia coli : Effects of Oxygen Transfer on Yield and Gene Expression.

The molecule (2 S )-naringenin is a scaffold molecule with several nutraceutical properties. Currently, (2 S )-naringenin is obtained through chemical synthesis and plant isolation. However, these methods have several drawbacks. Thus, heterologous biosynthesis has emerged as a viable alternative to its production. Recently, (2 S )-naringenin production studies in Escherichia coli have used different tools to increase its yield up to 588 mg/L. In this study, we designed and assembled a bio-factory for (2 S )-naringenin production. Firstly, we used several parametrized algorithms to identify the shortest pathway for producing (2 S )-naringenin in E. coli , selecting the genes phenylalanine ammonia lipase ( pal ), 4-coumarate: CoA ligase ( 4cl ), chalcone synthase ( chs ), and chalcone isomerase ( chi ) for the biosynthetic pathway. Then, we evaluated the effect of oxygen transfer on the production of (2 S )-naringenin at flask (50 mL) and bench (4 L culture) scales. At the flask scale, the agitation rate varied between 50 rpm and 250 rpm. At the bench scale, the dissolved oxygen was kept constant at 5% DO (dissolved oxygen) and 40% DO, obtaining the highest (2 S )-naringenin titer (3.11 ± 0.14 g/L). Using genome-scale modeling, gene expression analysis (RT-qPCR) of oxygen-sensitive genes was obtained.