Biosynthesis of Ethanol Using E.coli System

Group 11

生資所碩士班 924287 呂博凱 資工系博士班 928309 陳炯勳 資工系碩士班 924360 唐宗麟

Nov 19, 2004

Questions

• The usage of ethanol.• The metabolic pathways involved in the synthesis of ethanol.• The enzymes and genes involved in the biosynthesis pathway

of ethanol.• Is E. Coli suitable for biosynthesis of ethanol? • Propose experiments to determine the metabolic fluxes of the

network associated with ethanol .• Propose ways to maximize yield of ethanol .

The usage of ethanol

• Ethanol is a good fuel for internal combustion engines.It is less flammable than gasoline, and water is effective against ethanol fires.Its high octane rating, low pollutant emissions, and lower flammability must be weighed against its lower energy content.

• It is relatively less toxic solvent compared with hazardous solvents such as benzene and chloroform.

• It is the reactant to produce aldehyde or acid.

The metabolic pathways involved in the synthesis of ethanol

• Use KEGG website. http://www.genome.jp/kegg/

• Pick the “KEGG Table of Contents” link.

• Pick “KEGG LIGAND Database” and search ethanol ligand.

• Select “Escherichia coli K-12 MG1655” strain.

The metabolic pathways involved in the synthesis of ethanol (1)

Green background:

Enzymes can be found in E.coli K-12 MG1655 strain.

Red line:

The possible metabolic pathways involved in the biosynthesis of ethanol.

The metabolic pathways involved in the synthesis of ethanol (2)

Green background:

Enzymes can be found in E.coli K-12 MG1655 strain.

Red line:

The possible metabolic pathways involved in the biosynthesis of ethanol.

The enzymes and genes involved in the biosynthesis pathway of ethanol

(1) Enzyme name: protein-N (pi)-phosphohistidine-sugar phosphotransferase

EC: 2.7.1.69; Gene name: ptsG, glcA, umg

(2) Enzyme name: glucose-6-phosphate isomerase

EC: EC: 5.3.1.9

Gene name: pgi

The enzymes and genes involved in the biosynthesis pathway of ethanol

(3) Enzyme name:6-phosphofructokinase isozyme 2 (phosphofructokinase-2)

EC: 2.7.1.11 ; Gene name: pfkB

(4) Enzyme name: fructose-bisphosphate aldolase, class I

EC: 4.1.2.13 ; Gene name: dhnA

The enzymes and genes involved in the biosynthesis pathway of ethanol

(5) Enzyme name:glyceraldehyde-3-phosphate dehydrogenase

EC: 1.2.1.12 ; Gene name:gapC_2

(6) Enzyme name:acylphosphate phosphohydrolase

EC:2.7.2.3 ; Gene name: pgk

(6)‘ EC:3.6.1.7 ; Gene name:yccX

The enzymes and genes involved in the biosynthesis pathway of ethanol

(7) Enzyme name: phosphoglycerate mutase

EC: 5.4.2.1 ; Gene name:gpmA, gpm

(8) Enzyme name: enolase EC: 4.2.1.11 ; Gene name:eno

The enzymes and genes involved in the biosynthesis pathway of ethanol

(9) Enzyme name: pyruvate kinase I (PK-1) EC: 2.7.1.40 ; Gene name:pykF

(10) Enzyme name:pyruvate dehydrogenase E1 component

EC: 1.2.4.1 ; Gene name:aceE

The enzymes and genes involved in the biosynthesis pathway of ethanol

(11) Enzyme name:dihydrolipoamide acetyltransferase component (E2)

EC: 2.3.1.12 ; Gene name:aceF

The enzymes and genes involved in the biosynthesis pathway of ethanol

(13) Enzyme name: aldehyde dehydrogenase EC: 1.2.1.3 ; Gene name:aldH

(12) Enzyme name: acetyl-CoA synthetase

EC: 6.2.1.1 ; Gene name:acs

The enzymes and genes involved in the biosynthesis pathway of ethanol

(14) Enzyme name:alcohol dehydrogenase class III

EC: 1.1.1.1 ; Gene name:adhC

Is E. Coli suitable for biosynthesis of ethanol?

Pathway1It is necessary to find some ways that increase the flow of reaction 12.

Pathway2We can overexpression enzyme x (EC:4.1.1.1) to produce reaction 15.

Pathway 2

Pathway 1