Efficient biofuel generation using genetically modified bacteria and copper

cu15288 - Genetically engineered bacteria are promising tools for generating biofuels and commodity chemicals from carbon dioxide and iron(II). However, the product of this reaction, iron(III), is poorly soluble and has prevented bacterial biofuel generation from achieving its full potential. This technology couples bacterial iron oxidation to copper reduction-oxidation (redox) reactions to allow iron(III) to be reduced back to iron(II) in situ, increasing bioreactor energy density and improving the efficiency of the overall process. Moreover, the solid copper needed for this process can be economically extracted from low grade mineral ores using genetically modified acid-producing bacteria. This technology has the potential to reduce the cost of bioreactors and increase the rate of biofuel production. This technology is able to achieve more efficient biofuel production by using copper to reduce iron(III) to iron(II). However, a significant fraction of the earth’s copper supply is locked in the mineral chalcopyrite, from which it is not economically feasible to use traditional pyrometallurgical processes to extract copper. Here, genetically modified biomining organisms are used to produce organic acids and other compounds that can increase the dissolution of chalcopyrite and enhance the efficiency of copper extraction. Additionally, the use of copper in this approach enables this technology to seamlessly integrate with existing biomining processes that use bacteria to convert copper to cupric ions while also reducing iron(III) to iron(II). The regeneration of iron(II) during copper solubilization allows iron-oxidizing bacteria to continuously oxidize iron, fix carbon dioxide, and produce petrochemicals. This technology is fully compatible with existing bioreactor designs and can be easily incorporated into existing biomining operations. As such, the technology can help to minimize development costs while increasing bioreactor production rates. Alan West, Ph.D. Patent Pending (WO/2015/200287) Tech Ventures Reference: IR CU14270, IR CU15288