01851nas a2200169   4500008004100000245009800041210006900139260000800208300001000216490000800226520121500234100003201449700002501481700003101506700002101537856012301558       2018                        eng d00a Integrated constraints based analysis of an engineered violacein pathway in escherichia coli0 aIntegrated constraints based analysis of an engineered violacein  cSEP  a10-190 v1713 aStrategies towards optimal violacein biosynthesis, a potential drug molecule, need systems level coordination of enzymatic activities of individual genes in a multigene operon vioABCDE. Constraints-based flux balance analysis of an extended iAF1260 model (iAF1260vio) with a reconstructed violacein module predicted growth and violacein yields in Escherichia coli accurately. Shadow price (SP) analysis identified tryptophan metabolism and NADPH as limiting. Increased tryptophan levels in Delta pgi & Delta pheA were validated using in silico gene deletion analysis. Phenotypic phase plane (PhPP) analysis highlighted sensitivity between tryptophan and NADPH for violacein synthesis at molar growth yields. A synthetic VioABCDE operon (SYNO) sequence was designed to maximize Codon Adaptive Index (CAI: 0.9) and tune translation initiation rates (TIR: 2-50 fold higher) in E. coli. All pSYN E. coli transformants produced higher violacein, with a maximum six-fold increase in yields. The rational design E. coli: Delta pheA SYN: gave the highest violacein titers (33.8 mg/I). Such integrated approaches targeting multiple molecular hierarchies in the cell can be extended further to increase violacein yields.1 aImmanuel, Selva, Rupa Chris1 aBanerjee, Deepanwita1 aRajankar, Mayooreshwar, P.1 aRaghunathan, Anu  uhttps://library.ncl.res.in/content/integrated-constraints-based-analysis-engineered-violacein-pathway-escherichia-coli