3P-410 : Enhancing the tyosine production from acetate in Escherichia coli by optimization of glyoxylate cycle

L-tyrosine is a commercially important amino acid in industry. We attempt to control translation-level expression and carbon flux rebalancing around phosphoenolpyruvate (PEP) node. To optimize the L-tyrosine biosynthetic pathway, a synthetic constitutive promoter and a synthetic 5′-untranslated region (5′-UTR) were introduced for each gene of interest to allow for control at both transcription and translation levels. Carbon flux rebalancing was achieved by controlling the expression level of PEP synthetase using UTR Designer. The L-tyrosine productivity of the engineered E. coli strain was increased through pathway optimization resulting in 3.0g/L of L-tyrosine titer, 0.0354g L-tyrosine/h/g DCW of productivity, and 0.102g L-tyrosine/g glucose yield. Thus, this work demonstrates that pathway optimization by 5′ -UTR redesign is an effective strategy for the development of L-tyrosine-producing bacteria.