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Due to global warming and rising price of fossil fuel, microbial production of bio-fuel from organic byproducts has acquired significance in recent years. Over the few years ethanol has been trusted as an alternate fuel for the future. The ethanologenic pathway in Z. mobilis (Zymomonas mobilis), like that of Saccharomyces cerevisiae, consist of two essential activities, pyruvate decarboxylase (pdc) and alcohol dehydrogenase (adh). E. coli was able to ferment sugars into ethanol by inserting Z. mobilis genes encoding pyruvate decarboxylase and alcohol dehydrogenase II. These two enzymes produces 30 to 50% of the soluble proteins which activates the glycolysis pathway in Z. mobilis. In this study expression vector carrying pdc and adhB genes were constructed by using pSTV28 vector. Ethanol productivity of E. coli strains were thoroughly affected by the expression of pdc gene along with adhB genes. By successful gene mutation we will establish in constructing new E. coli strains that produces ethanol efficiently. Also to confirm the production of ethanol, fermentation experiment of recombinant ethanolic E. coli MG1655 and E. coli W3110 are going to be performed in aerobic conditions. Also to increase the ethanol productivity, galP (D-galactose transporter) gene and glk (glucokinase) gene in both E. coli strains were over-expressed by the expression vector ptrc99a. To confirm the production of ethanol in these new recombinant E. coli strains, fermentation experiment in aerobic conditions are also going to be performed. Pretreatment of marine algae were also going to be used as the culture medium of the aerobic fermentation experiments preformed by mutated E. coli strains as above.