@article {45413,
	title = { Integrated constraints based analysis of an engineered violacein pathway in escherichia coli},
	journal = {Biosystems },
	volume = {171},
	year = {2018},
	month = {SEP},
	pages = {10-19},
	type = {Article},
	abstract = {Strategies 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.},
	doi = {10.1016/j.biosystems.2018.06.002},
	author = {Immanuel, Selva Rupa Christinal and Banerjee, Deepanwita and Rajankar, Mayooreshwar P. and Raghunathan, Anu}
}
