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Metabolic Engineering of Escherichia coli for Production of Mixed-Acid Fermentation End Products.

Förster AH, Gescher J - Front Bioeng Biotechnol (2014)

Bottom Line: Mixed-acid fermentation end products have numerous applications in biotechnology.This is probably the main driving force for the development of multiple strains that are supposed to produce individual end products with high yields.The process of engineering Escherichia coli strains for applied production of ethanol, lactate, succinate, or acetate was initiated several decades ago and is still ongoing.

View Article: PubMed Central - PubMed

Affiliation: Institute of Applied Biosciences, Karlsruhe Institute of Technology , Karlsruhe , Germany.

ABSTRACT
Mixed-acid fermentation end products have numerous applications in biotechnology. This is probably the main driving force for the development of multiple strains that are supposed to produce individual end products with high yields. The process of engineering Escherichia coli strains for applied production of ethanol, lactate, succinate, or acetate was initiated several decades ago and is still ongoing. This review follows the path of strain development from the general characteristics of aerobic versus anaerobic metabolism over the regulatory machinery that enables the different metabolic routes. Thereafter, major improvements for broadening the substrate spectrum of E. coli toward cheap carbon sources like molasses or lignocellulose are highlighted before major routes of strain development for the production of ethanol, acetate, lactate, and succinate are presented.

No MeSH data available.


Related in: MedlinePlus

Anaerobic fermentative metabolism in Escherichia coli. Chemical structures are shown for all mixed-acid fermentation products and pyruvic acid. Bold gray arrows: glucose transport systems; thin black arrows: glycolysis; bold black arrows: fermentative reactions; dashed, green arrows: TCA cycle, only anabolic functions, completely active under oxic conditions. Genes: malEFG (maltose ABC transporter), galP (galactose:H+ symporter), ptsG (fused glucose-specific PTS enzyme: IIB and IIC component), manXYZ (mannose PTS permease), glk (glucokinase), pgi (glucose-6-phosphate isomerase), pfk (6-phosphofructokinase), fba (fructose-bisphosphate aldolase), tpi (triosephosphate isomerase), gap (glyceraldehyde 3-phosphate dehydrogenase), pgk (phosphoglycerate kinase), gpm (phosphoglycerate mutase), eno (enolase), pyk (pyruvate kinase), ppc (phosphoenolpyruvate carboxylase), ldhA (lactate dehydrogenase), pfl (pyruvate formate lyase), aceEF (pyruvate dehydrogenase complex), adhE (alcohol dehydrogenase), pta (phosphate acetyltransferase), ack (acetate kinase), gltA (citrate synthase), acnB (aconitase), icd (isocitrate dehydrogenase), sucA (2-oxoglutarate decarboxylase), sucB (2-oxoglutarate dehydrogenase), sucCD (succinyl-CoA synthetase), sdhABCD (succinate dehydrogenase), fumB (fumarate hydratase), frd (fumarate reductase), and mdh (malate dehydrogenase).
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Figure 1: Anaerobic fermentative metabolism in Escherichia coli. Chemical structures are shown for all mixed-acid fermentation products and pyruvic acid. Bold gray arrows: glucose transport systems; thin black arrows: glycolysis; bold black arrows: fermentative reactions; dashed, green arrows: TCA cycle, only anabolic functions, completely active under oxic conditions. Genes: malEFG (maltose ABC transporter), galP (galactose:H+ symporter), ptsG (fused glucose-specific PTS enzyme: IIB and IIC component), manXYZ (mannose PTS permease), glk (glucokinase), pgi (glucose-6-phosphate isomerase), pfk (6-phosphofructokinase), fba (fructose-bisphosphate aldolase), tpi (triosephosphate isomerase), gap (glyceraldehyde 3-phosphate dehydrogenase), pgk (phosphoglycerate kinase), gpm (phosphoglycerate mutase), eno (enolase), pyk (pyruvate kinase), ppc (phosphoenolpyruvate carboxylase), ldhA (lactate dehydrogenase), pfl (pyruvate formate lyase), aceEF (pyruvate dehydrogenase complex), adhE (alcohol dehydrogenase), pta (phosphate acetyltransferase), ack (acetate kinase), gltA (citrate synthase), acnB (aconitase), icd (isocitrate dehydrogenase), sucA (2-oxoglutarate decarboxylase), sucB (2-oxoglutarate dehydrogenase), sucCD (succinyl-CoA synthetase), sdhABCD (succinate dehydrogenase), fumB (fumarate hydratase), frd (fumarate reductase), and mdh (malate dehydrogenase).

Mentions: Under fermentative conditions, a mixture of succinate, formate, acetate, lactate, and ethanol is produced to maintain redox balance (Clark, 1989). Ethanol formation is established using alcohol dehydrogenase (adhE), which catalyzes the reaction from acetyl-CoA to ethanol with the consumption of two NADH molecules. The production of lactate is catalyzed by the soluble lactate dehydrogenase (ldhA) via reduction of pyruvate (consumption of one NADH molecule). Succinate formation starts with the carboxylation of phosphoenolpyruvate to oxaloacetate by PEP-carboxylase (ppc), and is subsequently achieved via the activity of malate dehydrogenase (mdh), fumarase (fumB), and fumarate reductase (frd) (Figure 1).


Metabolic Engineering of Escherichia coli for Production of Mixed-Acid Fermentation End Products.

Förster AH, Gescher J - Front Bioeng Biotechnol (2014)

Anaerobic fermentative metabolism in Escherichia coli. Chemical structures are shown for all mixed-acid fermentation products and pyruvic acid. Bold gray arrows: glucose transport systems; thin black arrows: glycolysis; bold black arrows: fermentative reactions; dashed, green arrows: TCA cycle, only anabolic functions, completely active under oxic conditions. Genes: malEFG (maltose ABC transporter), galP (galactose:H+ symporter), ptsG (fused glucose-specific PTS enzyme: IIB and IIC component), manXYZ (mannose PTS permease), glk (glucokinase), pgi (glucose-6-phosphate isomerase), pfk (6-phosphofructokinase), fba (fructose-bisphosphate aldolase), tpi (triosephosphate isomerase), gap (glyceraldehyde 3-phosphate dehydrogenase), pgk (phosphoglycerate kinase), gpm (phosphoglycerate mutase), eno (enolase), pyk (pyruvate kinase), ppc (phosphoenolpyruvate carboxylase), ldhA (lactate dehydrogenase), pfl (pyruvate formate lyase), aceEF (pyruvate dehydrogenase complex), adhE (alcohol dehydrogenase), pta (phosphate acetyltransferase), ack (acetate kinase), gltA (citrate synthase), acnB (aconitase), icd (isocitrate dehydrogenase), sucA (2-oxoglutarate decarboxylase), sucB (2-oxoglutarate dehydrogenase), sucCD (succinyl-CoA synthetase), sdhABCD (succinate dehydrogenase), fumB (fumarate hydratase), frd (fumarate reductase), and mdh (malate dehydrogenase).
© Copyright Policy - open-access
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4126452&req=5

Figure 1: Anaerobic fermentative metabolism in Escherichia coli. Chemical structures are shown for all mixed-acid fermentation products and pyruvic acid. Bold gray arrows: glucose transport systems; thin black arrows: glycolysis; bold black arrows: fermentative reactions; dashed, green arrows: TCA cycle, only anabolic functions, completely active under oxic conditions. Genes: malEFG (maltose ABC transporter), galP (galactose:H+ symporter), ptsG (fused glucose-specific PTS enzyme: IIB and IIC component), manXYZ (mannose PTS permease), glk (glucokinase), pgi (glucose-6-phosphate isomerase), pfk (6-phosphofructokinase), fba (fructose-bisphosphate aldolase), tpi (triosephosphate isomerase), gap (glyceraldehyde 3-phosphate dehydrogenase), pgk (phosphoglycerate kinase), gpm (phosphoglycerate mutase), eno (enolase), pyk (pyruvate kinase), ppc (phosphoenolpyruvate carboxylase), ldhA (lactate dehydrogenase), pfl (pyruvate formate lyase), aceEF (pyruvate dehydrogenase complex), adhE (alcohol dehydrogenase), pta (phosphate acetyltransferase), ack (acetate kinase), gltA (citrate synthase), acnB (aconitase), icd (isocitrate dehydrogenase), sucA (2-oxoglutarate decarboxylase), sucB (2-oxoglutarate dehydrogenase), sucCD (succinyl-CoA synthetase), sdhABCD (succinate dehydrogenase), fumB (fumarate hydratase), frd (fumarate reductase), and mdh (malate dehydrogenase).
Mentions: Under fermentative conditions, a mixture of succinate, formate, acetate, lactate, and ethanol is produced to maintain redox balance (Clark, 1989). Ethanol formation is established using alcohol dehydrogenase (adhE), which catalyzes the reaction from acetyl-CoA to ethanol with the consumption of two NADH molecules. The production of lactate is catalyzed by the soluble lactate dehydrogenase (ldhA) via reduction of pyruvate (consumption of one NADH molecule). Succinate formation starts with the carboxylation of phosphoenolpyruvate to oxaloacetate by PEP-carboxylase (ppc), and is subsequently achieved via the activity of malate dehydrogenase (mdh), fumarase (fumB), and fumarate reductase (frd) (Figure 1).

Bottom Line: Mixed-acid fermentation end products have numerous applications in biotechnology.This is probably the main driving force for the development of multiple strains that are supposed to produce individual end products with high yields.The process of engineering Escherichia coli strains for applied production of ethanol, lactate, succinate, or acetate was initiated several decades ago and is still ongoing.

View Article: PubMed Central - PubMed

Affiliation: Institute of Applied Biosciences, Karlsruhe Institute of Technology , Karlsruhe , Germany.

ABSTRACT
Mixed-acid fermentation end products have numerous applications in biotechnology. This is probably the main driving force for the development of multiple strains that are supposed to produce individual end products with high yields. The process of engineering Escherichia coli strains for applied production of ethanol, lactate, succinate, or acetate was initiated several decades ago and is still ongoing. This review follows the path of strain development from the general characteristics of aerobic versus anaerobic metabolism over the regulatory machinery that enables the different metabolic routes. Thereafter, major improvements for broadening the substrate spectrum of E. coli toward cheap carbon sources like molasses or lignocellulose are highlighted before major routes of strain development for the production of ethanol, acetate, lactate, and succinate are presented.

No MeSH data available.


Related in: MedlinePlus