KU Newsletter june2021 A history of leadership

Prof. Hyungdon Yun’s Team Presents a Thesis on Enzyme Engineering Using Unnatural Amino Acids

A research team of Prof. Hyungdon Yun from Department of Systems Biotechnology at Konkuk Institute of Science and Technology (KIT) has published a thesis on biocatalysis research using chemical modification or expanded amino acid alphabets on April 22nd in the online edition of <Chemical Reviews, IF=52.8>. The IF of Chemical Review is known to be higher than the top three major journals, Nature, Science and Cell. (View the thesis of Prof. Yun: https://doi.org/10.1021/acs.chemrev.0c01201)

Replacing existing organic reactions using eco-friendly biocatalytic (enzyme) reactions or developing a completely new reaction process using existing organic reactions is one of the core areas of applied biotechnology. Despite the remarkable success of enzyme engineering through directed evolution (The Noble Prize in Chemistry 2018), which is a method of improvement of enzyme in nature, and rational design, its optimization is fundamentally limited to 20 standard amino acids with limited functionality. However, the limitations can be overcome with the introduction of abiological chemical group into proteins. This process can be accomplished by (i) chemical modification of standard amino acid residues, (ii) the introduction of non-canonical amino acids into proteins and (iii) chemical modification using unnatural amino acids. The thesis covers the recent research achievements by systemically organizing the relevant research areas and presents strengths and weaknesses of various approaches as well as future research directions.

This thesis is supported by Mid-Career Researcher Program of National Research Foundation of Korea. A research team of Prof. Dawson from SCRIPPS and Prof. Taehyun Yoo from Ajou University participated as co-authors, and Amol Pagar (doctorate program) and Mahesh Patil (former research professor) shared co-first authorship for the thesis.

Prof. Yun’s research team has published ‘An Integrated Cofactor/Co‐Product Recycling Cascade for the Biosynthesis of Nylon Monomers from Cycloalkylamines’, a research result regarding biocatalysis technology development for the production of nylon monomers in , the authoritative journal of multidisciplinary chemistry last February. (https://doi.org/10.1002/anie.202012658)

The research team developed a multi-enzyme system that consumes cycloalkylamine and produces nylon monomers with high atomic efficiency without by-products. The research was also supported by Mid-Career Researcher Program of National Research Foundation of Korea, and Sharad Sarak (doctorate program) in Prof. Yun’s research team participated in as the first author.