A research team led by Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering at KAIST developed a new technology that enables production of phenol from glucose using an Escherichia coli (E. coli) strain. On October 11, the research was published online in Biotechnology Journal.

Phenol is an important commodity chemical used as the starting material for production of various industrial chemicals. Though they are mostly produced from fossil resources, phenol’s biological production from renewable resources has been restricted due to its toxicity to microorganisms. Because of this barrier, phenol’s production was limited to less than one gram per liter (g/L).

To solve this problem, the research team simultaneously engineered 18 E. coli strains for the production of phenol using synthetic regulatory small ribonucleic acid (sRNA) technology. This resulted in a successful production of phenol from glucose. The engineered strains showed significant improvements in the production and their tolerance to phenol. Among the strains, BL21 was found to the most effective strain in the production of phenol.

In order to minimize the toxicity of phenol in E. coli cells, biphasic fermentation process was also used in the research. This produced 3.79 g/L of phenol, which is the highest amount achieved by microbial fermentation, as compared to less than 1 g/L produced by existing means.

This research is expected to provide a strong basis for the microbial production of toxic chemicals and contribute to the development of biological engineering and industrial technology in the future. Doctor Byoungjin Kim, one of the co-authors of the research, said, “Using various types of synthetic biology technology, we were able to modify E. coli cells and produce phenol of highest concentration and productivity. The research is remarkable because it showed the possibility of production of chemicals that show toxicity toward microbes.”

This research was supported by the Intelligent Synthetic Biology Center through the Global Frontier Project of the Ministry of Science, ICT and Future Planning and the National Research Foundation of Korea.