Metabolic engineering E. coli

Aim Metabolic engineering E. coli phaCRc + ORFZck Poly(4HB) [90]... 

Zhu, M. M. Lawman, P. D. Cameron, D. C. Improving 1,3-propanediol production from glycerol in a metabolically engineered E.coli by reducing accumulation of glycerol-3-phosphate, Biotechnol. Prog., 2002, 18, 694-699. 

Further examples for the production of oHgosaccharides on the gram scale with metabolically engineered E. coli cells are summarized in Table 5.3 and Scheme 5.9. 

In this article, we review the development of processes for the production of RHAs in natural PHA-producing bacteria and metabolically engineered E. coli strains. 

There have been many successful cases of the development of metabolically engineered E. coli strains for the production of P(3HB), which is one of the best characterized PHAs. P(3HB) synthesis is initiated by condensation of two acetyl-CoA molecules into acetoacetyl-CoA, subsequently followed by reduction to 3-hydroxybutyryl-CoA using NADPH as a cofactor, and finally 3-hydroxybutyryl-CoA is incorporated into the growing chain of P(3HB) (Lee 1996). Because the P(3HB) synthesis pathway competes with inherent metabolic pathways needing acetyl-CoA, it is very important to increase the acetyl-CoA pool available for the P(3HB) synthesis reaction, resulting in increased P(3HB) yield and productivity. 

Isopropanol is currently synthesized via three different methods indirect hydration of propylene (also called the sulfuric acid process), direct hydration of propylene, and catalytic hydrogenation of acetone. Efforts have been made to produce isopropanol by utilizing the TA76 strain of metabolically engineered E. coli. After the alcohol accumulates in the culture, production drastically decreases. Isopropanol removal by gas stripping allows for the continuation of the conversion process. Further development of this process may result in an alternative route to propylene by the dehydration of bioisopropanol. 

Simkhada D, Knrumbang NP, Lee HC, Sohng JK (2010) Exploration of glycosylated flavonoids from metabolically engineered E. coli. Biotechnol Bioprocess Eng 15 754-760... 

Little is known about the current production levels of L-Phe, but in the early days of metabolic engineering 50 g L-1 of L-Phe, with a yield on glucose of 0.27 mol mol-1, was produced by an engineered E. coli [92]. This is near the theoretical limit [91] and one would surmise that in the starting species used by these authors some PEP-conserving mutations had been introduced via classical strain improvement. 

Antoine T, Priem B, Heyraud A, Greffe L, Gilbert M, Wakarchuk WW, Lam JS, Samain E. Large-scale in vivo synthesis of the carbohydrate moieties of gangliosides GMl and GM2 by metabolically engineered Escherichia coli. ChemBioChem 2003 4 406-412. 

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