서강대학교

초록/요약 도움말

Now days, human beings are encountering serious environmental problems such as; sudden climate change, increasing carbon dioxide emission and rapid natural oil decrease. Such phenomenon have become threatens to the human race. However, the demand for energy and essential chemical blocks in the industrial field is rapidly increasing. As a result, bio-refinery developmental system aimed to meet industrialization and economic growth without environment damages are emerging world-widely. Many chemicals that could only be produced by chemical processes in the past can now have the potential to be generated biologically using renewable resources. 2,3-Butanediol (2,3-BDO) production shows that the microbial production can alleviate the dependence on oil supply for the production of platform chemicals. Until now, it is known that 2,3-BDO production can be only conducted by microbial production. This microbial productive 2,3-BDO is one of the promising bulk chemical due to its extensive industry applications. 2,3-BDO is essential for the synthesis of various economically valuable biosynthetic products, since it can be converted into C4 industrial chemical blocks. Dehydration can convert 2,3-BDO into methyl ethyl ketone, which can be used as a liquid fuel additive, and 2,3-BDO can also be converted into 1,3-butadiene, which is a critical building block for synthetic rubber. In preparation for this research, microorganisms were screened for high 2,3-BDO productive microorganisms, and as a result Klebsiella pneumonia (K. pneumonia) was selected as the native 2,3-BDO producing host, and Escherichia coli was selected as the non-native 2,3-BDO producing host. The objective of this research is enhancing 2,3-BDO biosynthesis by metabolic engineered Klebsiella pneumonia and Escherichia coli. Based on the genome sequencing and metabolic network analysis data, necessary genes involved in the 2,3-BDO biosynthesis were manipulated or eliminated. Especially, gene over-expression and deletion methods for K. pneumoniaKCTC2242 were developed throughout the research providing tool for gene manipulation. Furthermore, enantio-pure 2,3-BDO production was achieved by constructing a genetically modified Escherichia coli for 2,3-BDO production.