| 초록 |
L-Tyrosine is an important compound because it is used as the precursors of drugs and the other valuable chemicals. For several decades, many attempts for L-tyrosine production by microbes were made to increase L-tyrosine production. However, these efforts were not sufficient to maximize L-tyrosine production due to metabolic flux imbalance around PEP node between L-tyrosine synthetic pathway and TCA cycle. Recently, we have developed a model to predict expression level named “UTR Designer” and we could precisely control expression level of the key enzyme. In this study, nascent genetic elements of L-tyrosine biosynthesis enzymes were replaced by synthetic promoters and 5’UTR designed for maximum expression and carbon flux around cell growth and production at PEP node was optimized by testing various expression levels of ppsA. Finally, we could obtain the strain with 1g/L titer and 30mg∙L-1∙h-1∙gDCW-1 specific productivity. This work demonstrated that L-tyrosine production pathway could be further optimized by precise expression control around the critical node using UTR Designer. |
