Efficiently Producing 2,3-Butanediol Via Genetic Modifications for Industrial Applications

Abstract

2,3-butanediol (BDO) is a chemical that is effective in the production of insecticides, plastic coatings, and intermediates in pharmaceuticals and its (2R,3R)-BDO isomer has various potential applications by the US Department of Energy [2, 4]. Despite the various industries that the chemical could be used in, methods of producing 2,3-BDO and its isomers are too expensive for manufacturing, making production inefficient [3]. This problem has led scientists to explore more economical methods of production for industrial use. Currently, genetic modification is the leading solution to solving this problem. Microbiologists can now take isolated colonies of Bacillus licheniformis, a bacterium that is known to naturally produce 2-3-BDO, and carry out UV-random mutagenesis to remove its mucoid forming features, increasing the production of bacillus plasmids and the efficiency of fermentation. This UV mutant strain is able to produce 2,3-BDO faster than the non-mutant parent strain, however, both strains produce (2R,3R)-BDO and (2R,3S)-BDO isomers in a 1:1 ratio. This has resulted in recent progress in experimentation for isomer selectivity. Non-mucoid strains of B. lichenformis can undergo gene deletion in order to guarantee stereospecific isomers produced during fermentation. This genetically modified strain does not produce as much overall 2,3-BDO but is able to selectively produce the intended isomer. This revolutionary method of modifying bacteria shows the potential that genetic modification has on bringing an effective chemical back to the market in an economical and efficient way, but lacks evidence supporting a way to selectively mass produce the stereospecific isomers.