Research Support

Establishment of a high-throughput biological assay for enhanced production of branched-chain alcohols

Project Gist

Evaluation and screening of bioproduction by sensor cells


Genome-wide screening, Alcohol tolerance, Bioassay, Co-culture, Isobutanol

Background and Purpose

To realize sustainable society, it is important how to construct microorganisms that produce useful substances efficiently. With regard to isobutanol, which is promising as a next-generation fuel, there is no method to comprehensively select cells that show high productivity. Therefore, the limited development strategies have become one of the factors that delay the progress of constructing useful microorganisms. In this project, we aimed to establish a novel bioassay system for efficiently selecting cells that produce high amount of isobutanol without the need for expensive analytical instruments.

Project Achievements

We identified yeast strains that show severe growth inhibition in the presence of isobutanol while ethanol does not cause their growth inhibition. The concentration of isobutanol can be estimated by examining the cell growth of these yeast strains as sensor cells. At the same time, we have identified a yeast strain with an interesting feature of enhanced tolerance specifically to branched-chain alcohols such as isobutanol. When isobutanol was produced in this tolerant strain by introducing enzyme genes of isobutanol biosynthesis pathway, the production amount was greatly improved as compared to wild type strain. Furthermore, one of the mechanisms underlying enhanced tolerance was also elucidated. Through this project, we were able to expand and deepen the international network.

Future Prospects

We would like to construct yeasts with further improved isobutanol production ability by high-throughput screening with the constructed sensor cells. We plan to elucidate the mechanism by which cells recognize branched-chain alcohols.


Visit to MIT, meeting on collaborative project with Prof. Stephanopoulos and Prof. Fink
Visit to Princeton University, meeting on collaborative project with Prof. Avalos

Joint Research/Academic Institutions Abroad

Massachusetts Institute of Technology, Whitehead Institute for Biomedical Research, Princeton University

Principal Investigator

KURODA Kouichi

・KURODA Kouichi
・Graduate School of Agriculture
・He received a Ph.D. in Engineering from Kyoto University. He has been working on understanding life phenomena, developing novel bio-research tools, and constructing useful microorganisms.