Table 1 Metabolic engineering approaches to improve biobutanol production by bacteria
Bacteria and engineering technique | Fuel concentration | Productivity | Reference |
|---|---|---|---|
g/L | g/LÂ h | ||
Clostridium acetobutylicum not engineered | B: 8.3 | nr | [17] |
Clostridium beijerinckii engineered to use liquefied corn flour + product recovery | ABE: 81.3 | nr | [18] |
Hyper butanol producing strain of Clostridium pasteurianum isolated by chemical mutagenesis and optimized to produce butanol from glycerol in bach culture | B: 17.8 | B: 0.43 | [19] |
Idem to previous in continuous culture | nr | ABE: 8.30 | [19] |
B: 7.80 | |||
Clostridium ljungdahlii engineered to use a mixture of hydrogen and carbon monoxide | butanol produced, but only detectable during middle growth phase, then it is metabolized to butyrate | [20] | |
Clostridium acetobutylicum engineered by inactivation of the adc gene, encoding the acetoacetate decarboxylase and necessary for acetone synthesis. | B: 14.8 | nr | [21] |
BE: 18.1 | |||
Clostridium acetobutylicum engineered with a synthetic operon for obtaining isopropanol from acetone | IBE: 35.6 | IBE 0.83 | [22] |
Clostridium acetobutylicum engineered for obtaining isopropanol from acetone | IBE: 27.9 | nr | [23] |
Clostridium ljungdahlii transformed with a plasmid, carrying the C. acetobutylicum butanol synthesis pathway genes | B: 0.15* | [24] | |
Escherichia coli engineered to produce isopropanol and butanol with genes from C. acetobutylicum and others | I: 4.9 | I: 0.4 B: nr | [25] |
B: 0.5 | |||
Escherichia coli engineered to produce butanol with genes from C. acetobutylicum | B: 0.20-0.58 | nr | [26] |
Pseudomonas putida engineered to produce butanol with genes from C. acetobutylicum | B: 0.12 | nr | [26] |
Bacillus subtilis engineered to produce butanol with genes from C. acetobutylicum | B: 0.02 | nr | [26] |
Lactobacillus brevis engineered to produce butanol with genes from C. acetobutylicum | B: 0.30 | nr | [17] |
Synthetic butanol pathway expressed in Escherichia coli | B: 4.65 | nr | [27] |
Modified Escherichia coli by the 2-keto-acid pathway | B: 20 | B: 0.18 | [25] |
Modified Corynebacterium glutamicum by the 2-keto-acid pathway | B: 4.9 | nr | [28] |