Paper Title
Enhanced Bioethanol Production From Metabolic Engineering Of Enterobacter Aerogenes Atcc 29007

Abstract
This study investigates the enhancement of bioethanol production using a genetic engineering approach. The bioethanol-producing strain, E. aerogenes ATCC 29007, was engineered by deleting the D-lactate dehydrogenase (ldhA) gene to block the production of lactic acid. The colony PCR was used to confirm the deleted gene. Glycerol, a useful byproduct in the biodiesel industry, was employed to convert into bioethanol, using engineered E. aerogenes SUMI014. Under optimal conditions of fermentation (34 C, pH 7.5, 78 h), bioethanol production by the mutant strain was 34.54 g/L, 1.5 times greater than that produced by its wild type (13. 09 g/L). Subsequent overexpression of alcohol dehydrogenase (adhE) gene in the mutant strain; increased the production of bioethanol up to 38.32 g/L. By the combination of gene deletion and overexpression, the bioethanol yield was 0.48 g/g when employing 80 g/L glycerol. Hence, a significant enhancement in ethanol production was observed. Keywords- Alcohol dehydrogenase, D-lactate dehydrogenase, Enterobacter aerogenes ATCC29007, Enterobacter aerogenes SUMI014, Enterobacter aerogenes SUMI2008