Ethanol genetic manipulation

Efforts for the isolation or genetic manipulation of ethanol-resistant strains, which are less sensitive to alcohol inhibition 19), are being made. The selection of thermotolerant and thermophilic strains is feasible 20). 

The activities of XR and XDH decreased with the increase in oxygen limitation (Fig. 4a), which indicated that an increase in XR and XDH activities could lead to the increase in xylose metabolic rate. Karhumaa et al. [30] increased XR and XDH activities in Saccharomyces cerevisiae by genetic manipulation, which significantly increased ethanol but decreased xylitol productions. Not only XR and XDH activities but also the XR/XDH... 

Ethanol precipitation is used to purify and concentrate the genetic manipulation plasmids prior to electroporation. The following procedure is performed in micro-centrifuge tubes. Reagents should be prepared with sterile deionized... 

Due to their prokaryotic nature the genetic manipulation of bacteria is much easier than that of yeasts. Nevertheless, much effort has been undertaken in the last years to manipulate the more ethanol tolerant yeasts towards the ability to metabolize C-5 sugars, especially xylose and arabinose. Further, ethanol yields of about 20-30 gL are still too low to make these organisms industrially profitable. 

Luo LH, Seo P, Seo J, Heo S, Kim D. (2009). Improved ethanol tolerance in Escherichia coli by changing the cellular fatty acids composition through genetic manipulation. Biotechnol Lett,3, 1867-1871. 

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