1,3 propanediol production

Draft plan of report

Outline

• Basic traits of 1,3 pdiol ( background knowledge)

• Important application

• Why bioengineering

• Modern biotech methods

Compare and contrast

• Metabolic pathway

• Confined situation (made up, or based on successful industrial facts)

• Compute and compare different species’ strategy via calculating kinetics

• Specific production amount/ quantity

• conclusion

• Group 1 Project Draft : Production of 1,3-Propandiol through Metabolic Engineering(Executive Summary).

• *Group 1(heretofore referred to as we) shall apply the anaerobic fermentation of glycerol which allows the use of renewable feedstock rather than heterogeneous catalysis routes that are dependent on petrochemical feedstocks such as ethylene oxide or acrolein (because in the light of the current global climate crises,namely global-warming,we’ve got to be environmentally-friendly in our industrial applications.Furthermore, even though D-glucose fed-batch 10Litre fermentations result in the production of 1,3 –propandiol of 3.5 g/L/h,a titre of 135g/L and a weight yield of 51% ,we shall use the biological method of anaerobic fermentation of glycerol in our production of 1,3-propandiol through metabolic engineering aiming at production maximum values for rate, titer and weight-yield of 1,3-propandiol of 3.0g/L/h,78g/L titer and 55% weight-yield respectively using metabolically engineered Klebsiella pneumoniae (or Clost ridium butyricum)(because it has a higher weight yield).Thus,we intend executing production using the biological pathway as follows :-

• Glycerol + 2e- + 2H using Glycerol dehydratase from biotech-engineered Klebsiella pneumoniae to produce 1,3 –propandiol and water molecules.

• The simplicity of the bioklogical path-way is self-evident.In the anaerobic fermentation,metabolic engineering expands the range of chemical process solutions through the direct fermentation of glycerol based on natural biological routes ;expanding the glycerol-based natural process based on the lower cost carbon feed-stock uptake(transport)mechanism of the host organism,the intergeneric transfer of the complex metabolic pathways as both the design and implementation of an optimal solution to the balance of both the carbon and redox energy balance with respect to microbial growth and product formation.

• *We shall use the enzyme glycerol dehydratase from the bacteria Klebsiella pneumoniae (or Clost ridium butyricum) because detailed biochemical evaluation and molcular characterization have confirmed its B-12 independence and have also seen to the evaluation of its anaerobic processes for the production of 1,3-propandiol.Conclusively,the production of 1,3-propandiol using metabolically-engineered microorganisms involves the anaerobic (and oxidative) consumption of glycerol in order to produce cell mass as well as the collection of Acetate and reduced Nicotinamide Adenine Dinucleotide(NADH) as by-products: it is essential that the NADH is converted into NAD within the cells at a steady state.Consequently, the NAD is regenerated via the reductive conversion of glycerol to 1,3-propandiol in two steps namely:-

• Step(1.)Involving the dehydration of glycerol to form 3-hydroxypropionaldehyde(3-HPA) and is catalyzed by glycerol dehydratase encoded by the genes (dhaB1-3) .

• Step(2.)Involving the NADH-dependent reduction of 3-hydroxypropionaldehyde(3-HPA) into 1,3 -propandiol and is catalyzed by 1,3-propandiol oxidoreductase enzyme (encoded by the dha T gene).

• *In conclusion,my group (group 1)has decided to use the biochemical pathway aforementioned rather than integrating the dhaB and yqhD genes into the chromosome of Saccharomyces Cerevisiae by Agrobacterium tumefaciens –mediated transformation and then constructing the new strain W303-1A-ZR because it’s a far much more slower,cumbersome and rigorous pathway and can only produce 1,3-propandiol directly using D-glucose as a substrate and cannot utilize glycerol.