## 4 Production of Plant Secondary Metabolites Using Microbial Chassis
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Compound** & **Product** & **Host** & **Engineering Strategy** & **Titer (mg/L)** & **Vessel** & **Ref.** \\ \hline \multirow{6}{*}{Artemismic acid} & \multirow{2}{*}{_S. cerevisiae_} & Down-regulation of ERG9 under & \multirow{2}{*}{25,000} & \multirow{2}{*}{Flask} & \multirow{2}{*}{[167]} \\  & & CTR3 promoter in response to & & & \\  & & copper and reductase CRP1 & & & \\ \hline \multirow{6}{*}{Differpenes} & \multirow{6}{*}{_S. cerevisiae_} & Additional introduction of CYB5, & \multirow{6}{*}{2500} & \multirow{6}{*}{Fermentor} & \multirow{6}{*}{[168]} \\  & & ADH1, and ALDH1 & & & \\ \hline \multirow{6}{*}{Diverpenes} & \multirow{6}{*}{_S. cerevisiae_} & ERG9 controlled with & \multirow{2}{*}{25} & \multirow{2}{*}{Fermentor} & \multirow{2}{*}{[169]} \\  & & promoter Pmet3 & & & \\ \hline \multirow{6}{*}{Differpenes} & \multirow{6}{*}{_S. cerevisiae_} & Rewiring central metabolism for & \multirow{2}{*}{11,400} & \multirow{2}{*}{Fermentor} & \multirow{2}{*}{[169]} \\  & & application of acetyl-CoA & & & \\  & & and NADPH & & & \\ \hline \multirow{6}{*}{Sclareol} & \multirow{6}{*}{Optimization of MVA pathway} & \multirow{6}{*}{11,400} & \multirow{6}{*}{Fermentor} & \multirow{6}{*}{[169]} \\  & & Fusion of twoiterpene synthase & & & \\  & & and maltose-binding protein & & & \\ \hline \multirow{6}{*}{Taxadiene} & \multirow{6}{*}{_E. coli_} & Knock-out regulatory factors & \multirow{6}{*}{1500} & \multirow{6}{*}{Flask} & \multirow{6}{*}{[170]} \\  & & Reconstruction of sclareol & \multirow{2}{*}{1500} & \multirow{2}{*}{Flask} & \multirow{2}{*}{[170]} \\  & & biosynthetic pathway & & & \\ \hline \multirow{6}{*}{Taxadiene} & \multirow{6}{*}{_E. coli_} & Optimally balanced expressions of & \multirow{6}{*}{1020} & \multirow{6}{*}{Fermentor} & \multirow{6}{*}{[171]} \\  & & up and downstream & & & \\ \cline{1-1}  & Pathway modules & & & & \\ \hline \multirow{6}{*}{Taxadiene} & \multirow{6}{*}{_S. cerevisiae_} & Two-phase cultivation & \multirow{6}{*}{184.2} & \multirow{6}{*}{Fermentor} & \multirow{6}{*}{[172]} \\  & & Fusion of GCPS and & \multirow{2}{*}{184.2} & \multirow{2}{*}{Fermentor} & \multirow{2}{*}{[173]} \\  & & taxadiene synthase & & & \\ \hline \multirow{6}{*}{Multiradiene} & \multirow{6}{*}{_S. cerevisiae_} & Overexpression of MVA pathway genes & \multirow{2}{*}{3500} & \multirow{2}{*}{Fermentor} & \multirow{2}{*}{[173]} \\  & & & pathway genes & & \\ \hline \multirow{6}{*}{Multiradiene} & Downregulation of transcription & \multirow{6}{*}{184} & \multirow{6}{*}{Fermentor} & \multirow{6}{*}{[172]} \\  & factor ROS1 and competing & & & & \\ \cline{1-1}  & enzyme ERG9 & & & & \\ \hline \multirow{6}{*}{Tirterpenes} & \multirow{6}{*}{_S. cerevisiae_} & Fusion of GCPP synthase and FPS; & \multirow{6}{*}{10.5} & \multirow{6}{*}{Flask} & \multirow{6}{*}{[174]} \\  & & fusion of copaly diphosphate & \multirow{6}{*}{174} & \multirow{6}{*}{Flask} & \multirow{6}{*}{[174]} \\  & & synthase and kaurene & & & \\ \cline{1-1}  & Ferruginol & & & & \\ \hline \hline \multirow{6}{*}{Tirterpenes} & \multirow{6}{*}{_S. cerevisiae_} & Semi-rational design of UGT51 & \multirow{2}{*}{300} & \multirow{2}{*}{Fermentor} & \multirow{2}{*}{[175]} \\  & & Ginresonoides & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: _Cont._  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Compound** & **Product** & **Host** & **Engineering Strategy** & **Titer (mg/L)** & **Vessel** & **Ref. ** \\ \hline \multirow{6}{*}{_S. cerevisiae_} & Modular engineering of the MVA & & & & \\  & & and optimization of P450 & 2250 & Fermentor & [176] \\  & & expression levels & & & \\ \hline \multirow{6}{*}{_S. cerevisiae_} & Increasing the copy number and & & & & \\  & expression level of UGTg45 and & & & & \\  & & direct evolution by random & & & \\  & & mutation & & & \\ \hline \multirow{6}{*}{_S.