Propanediol pathway

Altaras, N. E. Cameron, D. C. Metabolic engineering of a 1,2-propanediol pathway in E.coli, Appl. Environ. Microbiol., 1999, 65, 1180-1185. (b) Enhanced production of... 

Metabolic engineering of a 1, 2-propanediol pathway in Escherichia coli. Appl. Environ. Microbiol, 65, 1180-1185. 

Niimi, S., Suzuki, N., Inui, M., and Yukawa, H. (2011) Metabolic engineering of 1,2-propanediol pathways in Corynebacterium glutamicum. 

Boenigk R, Bowien S, Gottschalk G (1993) Fermentation of glycerol to PDO in continuous cultures of Citrobacter freundii. Appl Microbiol Biotechnol 38 453-457 Cameron DC, Altaras NE, Hoffman ML (1998) Metabolic engineering of propanediol pathways. Biotechnol Progr 14(116) 125... 

Cameron DC, Altaras NE, Hoffman ML, Shaw AJ. (1998). Metabolic engineering of propanediol pathways. Biotechnol Prog, 14,116-125. 

It is important that chemical engineers master an understanding of metabolic engineering, which uses genetically modified or selected organisms to manipulate the biochemical pathways in a cell to produce a new product, to eliminate unwanted reactions, or to increase the yield of a desired product. Mathematical models have the potential to enable major advances in metabolic control. An excellent example of industrial application of metabolic engineering is the DuPont process for the conversion of com sugar into 1,3-propanediol,... 

Several methods and reaction pathways have been reported for the conversion of glycerol in the literature, such as etherification, esterification [1], and oxidation [2], Via ionic dehydration acetol [3] and acrolein can be produced. The radical steps result in aldehydes, allyl alcohol, etc. [4], If the dehydration is followed by a hydrogenation step, propanediols (1,2- or 1,3-) can be obtained [5-6]. 

A palladium phosphine complex [e.g., BCPE = l,2-bis(l,5-cyclooctylenephos-phino)ethane] was also reported to produce propanediols and n-propanol from glycerol at 443 K under 6 MPa CO/H2 atmosphere in acidic conditions, n-Propanol is the dominant product, while a slight preference for the formation of propane-1,3-diol is seen in the diol fraction. Reactions were performed at different temperatures in the range 413-448 K. Since acrolein was monitored at high temperature, a reaction network was proposed following a sequential dehydration/hydrogenation pathway [20]. 

Propanediol. In its racemic form, 1,2-propanediol is a petroleum-based high-volume chemical with an aimual production of over 500,0001, mostly used to manufacture the unsaturated polyester resins, yet also featuring excellent antifreeze properties. Enantiomerically pure (/ )-1,2-propanediol accumulates along two different pathways via DAHP (3-deoxy-D-flrahmo-heptulosonic acid 7-phosphate) and methylglyoxal, which then is reduced with either... 

Acetone, in the small amounts normally present in the body, is metabolized by hydroxylation to acetol (Eq. 17-7, step a), hydroxylation and dehydration to methylglyoxal (step b), and conversion to D-lactate and pyruvate. A second pathway via 1,2-propanediol and L-lactate is also shown in Eq. 17-7. During fasting the acetone content of human blood may rise to as much as 1.6 mM. As much as two-thirds of this may be converted to glucose.65-69 Accumulation of acetone... 

This -ketoadipate pathway produces e.g., succinic acid, a compound used as monomer for the production of aliphatic polyesters. Already in 1881, the production of e.g., 1,3-propanediol by the fermentation of glycerol was reported [8],... 

Felbamate. Felbamate, chemically 2-phenyl-1,3-propanediol dicarbamate (10), is well absorbed after oral administration (68). Felbamate is distributed to all tissues and has been metabolized by several pathways in ani-... 

Cost-effective production of 1,3-propanediol, a new feedstock for polyesters, using a genetically engineered fermentation pathway (DuPont, 2003) ... 

Fig. 11. Pathways for the isomerization of 2-phospho-1,2-propane-diol to I -phospho-1,2-propanediol via (a) a cyclic intermediate or (b) pseudorotation. From Ref. 35.

The mpd genes involved in the early steps of the TBA catabolic pathway were recently isolated and characterized in M. austroafricanum lEP 2012 [38]. The enzymes encoded by these genes catalyzed the transformation of 2-methyl 1,2-propanediol (2M1, 2PD), the product of TBA oxidation, into HIBA. 

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