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Two Professors Receive the Asan Medical Award
(Professor Ho Min Kim and Chair Profesor Eunjoon Kim (from far right)
Chair Professor Eunjoon Kim of the Department of Biological Sciences and Professor Ho Min Kim from the Graduate School of Medical Science & Engineering won the 11th Asan Medical Award in the areas of basic medicine and young medical scholar on March 21.
The Asan Medical Award has been recognizing the most distinguished scholars in the areas of basic and clinical medicines annually since 2007.
Chair Professor Kim won the 300 million KRW award in recognition of his research in the mechanism of synaptic brain dysfunction and its relation with neural diseases.
The young medical scholar’s award recognizes a promising scholar under the age of 40. Professor Kim won the award for identifying the key protein structure and molecular mechanism controlling immunocytes and neurons. He earned a 50 million KRW prize.
2018.03.26 View 9278 -
KAIST-KU Sign MOU on 4th Industrial Technology Development
(President Shin(second from left) poses with Khalifa University President Tod Laursen after signing an MOU in the UAE on March 25. Far left is Chairman of the NST Kwangyun Wohn and far right is the UAE Minister of Educatiion Hussain Al Hammadi.)
KAIST President Sung-Chul Shin and Khalifa University Interim President Tod Laursen signed an MOU on the Fourth Industrial Technology Development on March 25 in the UAE.
They signed the MOU during the UAE-ROK Nuclear Friendship and KAIST Alumni Night at Khalifa University co-hosted by KAIST and the Korea Atomic Energy Research Institute (KAERI). The MOU will bring new opportunities to further expand bilateral cooperation in education and training in the relevant technologies called for the era of the Fourth Industrial Revolution.
More than 100 dignitaries including Chairman of National Research Council of Science and Technology (NST) in Korea Dr. Kwangyun Wohn, President of KAERI Jaejoo Ha, the UAE Minister of Education His Excellency Hussain Al Hammadi, Minister of State for Advanced Sciences Her Excellency Sarah bint Yousef Al Amiri, and His Excellency Federal Authority for Nuclear Regulation (FANR) Director General Christopher Viktorsson attended the event. In particular, a significant number of Emirati graduates of the KUSTAR-KAIST education program and many others who completed various KAIST training programs joined the event.
The Nuclear Friendship Night was celebrating the completion of the first nuclear power plant in Barakah exported by Korea. This is the first nuclear reactor in the Middle East, which is to start operation later this year. The event also coincided with Korean President Moon Jae-In’s state visit to the UAE.
KAIST and KAERI gathered distinguished leaders from the higher education and nuclear industries at the event in response to the UAE government’s top national agenda of fostering future talents and promoting the nuclear industry in order to ensure energy security.
KAIST and Khalifa University signed an initial agreement in education and research in 2009 when the governments of Korea and the UAE signed a contract to build four nuclear power plants in Barakah. Since then, the two universities have worked together closely in the areas of nuclear engineering, bio-medical engineering, robotics, mechanical engineering, chemical engineering, and materials science. With this signing on the new MOU, the partnership between the two institutions will mark the second phase of educating high-caliber human resources in science and technology of the two countries.
The KAIST Alumni Night also brought more opportunities to appreciate the achievements that the two countries have made through collaboration in education and research, mostly represented in the field of nuclear technology between KAIST and Khalifa University. During the event, KAIST graduates also shared their experiences from the education at KAIST, followed by the welcoming speeches from the UAE Minister of Education and the UAE Minister of State for Advanced Sciences.
KAIST President Shin, in his welcoming speech at the event, said, “I look forward to more students in the UAE having the opportunity to experience the world’s top-level education and global environment that KAIST offers. The collaboration with Khalifa University and the UAE is very important for building both countries’ future growth.”
KU President Laursen said, “This MOU on research cooperation focusing on technologies for the Fourth Industrial Revolution, nuclear engineering, and other technical areas will further consolidate our partnership with KAIST and support us in developing human capital suitable to take on future challenges in the science and technology sectors. We firmly believe the talent pool of experts created by this initiative will contribute to the overall economic growth of the UAE.”
2018.03.26 View 10208 -
Professor Emeritus Jung Ki Park Won the IBA Technology Award 2018
(Professor Emeritus Jung Ki Park)
Professor Emeritus Jung Ki Park from the Department of Chemical and Biomolecular Engineering received the IBA Technology Award from the International Battery Association (IBA).
IBA 2018 was held from March 11 to 16 on Jeju Island, which was the first time it was hosted in Korea. The conference was an excellent opportunity to let the world know the level of the Korean rechargeable battery industry and its technology.
Professor Park delivered his keynote speech titled Advances in Lithium Batteries in Korea at the conference and received the IBA Technology Award as the first Korean recipient.
Professor Park is a world-renowned scholar who was a groundbreaker in the rechargeable battery industry. He was recognized by the IBA Award Committee for his contributions carrying out research and development, fostering competent people, and enhancing the lithium rechargeable battery industry in Korea over the last 30 years.
Professor Park said, “It is my great honor to receive this award, which is the best international award in the field of rechargeable batteries. I would like to share this with my colleagues and students. As competition in the rechargeable industry intensifies, systemic cooperation among industries, academia, and government is needed for the continued development of the battery industry in Korea.
2018.03.19 View 7378 -
The 8th KINC Fusion Research Awardees
The KAIST Institute for NanoCentury held the 8th KINC Fusion Research Award in order to encourage professors’ convergence studies and instill students’ willingness to research. The award ceremony took place in the KI Building at KAIST on March 13.
The KINC Fusion Research Award selects the most outstanding convergence studies among research undertaken last year, and awards researchers who participated in that research.
The 8th KINC Fusion Research Award went to Professor Yoon Sung Nam from the Department of Materials Science and Engineering and Professor Inkyu Park from the Department of Mechanical Engineering. Their research reported the spontaneous self-biomineralization of palladium (Pd) ions on a filamentous virus to form ligand-free Pd nanowires without reducing reagents or using additional surface stabilizers (Title: Virus-Templated Self-Mineralization of Ligand-Free Colloidal Palladium Nanostructures for High Surface Activity and Stability, Advanced Functional Materials (2017)).
Professor Hee-Tae Jung, the Director of KAIST Institute for the NanoCentury and the host of the KINC Fusion Research Award said, “Convergence will be the crucial keyword that will lead to revolutionary change. Hence, the importance of convergence study should be improved. We will put every effort into creating a research environment for increasing convergence study.
The KAIST Institute for the NanoCentury was established in June 2006 under the KAIST Institute with a mission of creating convergence study by tearing down boarders among departments and carrying out interdisciplinary joint research. Currently, approximately 90 professors from 14 departments participate the institute. It aims to become a hub of university institutes for nano-fusion research.
2018.03.19 View 12515 -
Scientist of March, Professor Hee-Seung Lee
(Professor Hee-Seung Lee)
Professor Hee-Seung Lee from the Department of Chemistry at KAIST received the ‘Science and Technology Award of the Month’ awarded by the Ministry of ICT and Science, and the National Research Foundation of Korea for March 2018.
Professor Lee has been recognized for successfully producing peptide-based molecular machines, which used to be made of metals.
The methodology can be translated into magnetotactic behavior at the macroscopic scale, which is reminiscent of magnetosomes in magnetotactic bacteria.
The team employed foldectures, self-assembled molecular architectures of β-peptide foldamers, to develop the peptide-based molecular machines that uniformly align with respect to an applied static magnetic field.
Professor Lee said, “Molecular machines are widely used in the field of medical engineering or material science; however, there were limitations for developing the machines using magnetic fields. By developing peptide-based molecular machines, we were able to develop body-friendly molecular machines.”
Every month, the Ministry of ICT and Science and the National Research Foundation of Korea award a cash prize worth 10,000,000 KRW to a scientist who has contributed to science and technology with outstanding research and development performance.
2018.03.15 View 9517 -
KAIST Professors Selected as Y-KAST Members
Professor YongKeun Park, Professor Bumjoon Kim, Professor Keon Jae Lee, and Professor Young Seok Ju were selected as the newest members of the Young Korean Academy of Science and Technology (Y-KAST).
The Korean Academy of Science and Technology, an academic institution of professional experts, selected 26 promising scientists under the age of 43 to join Y-KAST. and four KAIST professors were included in the list.
The newest members were conferred on February 26.
Research Field
Name
Natural Sciences
YongKeun Park (Dept. of Physics)
Engineering
Bumjoon Kim (Dept. of Chemical and Biomolecular Engineering)
Agricultural & Fishery Sciences
Keon Jae Lee (Dept. of Materials Science and Engineering)
Medical Sciences
Young Seok Ju (Graduate School of Medical Science and Engineering)
2018.03.05 View 9442 -
Successful Synthesis of Gamma-Lanctam Rings from Hydrocarbons
(The team of Professor Chang, far right, at the Department of Chemistry)
KAIST chemists have designed a novel strategy to synthesize ring-shaped cyclic molecules, highly sought-after by pharmaceutical and chemical industries, and known as gamma-lactams. This study describes how these five-membered rings can be prepared from inexpensive and readily available feedstock hydrocarbons, as well as from complex organic molecules, such as amino acids and steroids.
Gamma-lactams find several applications in medicinal, synthetic, and material chemistry. For example, they are included in a large number of pharmaceutically active compounds with antibiotic, anti-inflammatory, and anti-tumoral functions. This research was published in Science on March 2.
Conversion of hydrocarbons into nitrogen-containing compounds is an important area of research, where the challenge lies in breaking strong carbon-hydrogen (C−H) bonds, and converting them into carbon-nitrogen (C–N) bonds in a controlled fashion. For this reason, hydrocarbons are difficult to use as starting materials, albeit the fact that they exist in large quantities in nature.
Over the last 35 years, chemists have found ways of converting simple hydrocarbons into nitrogen-containing rings, such as indoles or pyrrolidines, but gamma-lactams proved impossible to prepare using the same approaches. Researchers hypothesized that such failure was due to alternative chemical pathways that steer the reaction away from the wanted rings: The reaction intermediate (carbonylnitrene) quickly breaks down into unsought products. Using computer models of the desired and undesired reaction pathways, the team found a strategy to completely shut down the latter in order to obtain the longed-for gamma-lactams. For the first time, these four carbons and one nitrogen cyclic molecules were obtained directly from simple feedstock chemicals.
Led by Professor Chang Sukbok at the Department of Chemistry, the team designed the winning reaction with the help of computer simulations that analyze the reaction mechanisms and calculate the energy required for the reaction to take place. According to such computer predictions, the reaction could follow three pathways, leading to the formation of either the desired gamma-lactam, an unwanted product (isocyanate), or the degradation of the catalyst caused by the substrate reacting with the catalyst backbone. Combining experimental observations and detailed computer simulations, the team designed an iridium-based catalyst, highly selective for the gamma-lactam formation. In this way, the two undesired pathways were systematically shut down, leaving the formation of the nitrogen-containing ring as the only possible outcome. Professor Chang is also in charge of the Center for Catalytic Hydrocarbon Functionalizations at the Institute for Basic Science (IBS).
“With this work we offer a brand new solution to a long-standing challenge and demonstrate the power of what we call mechanism-based reaction development,” explains Professor Baik Mu-Hyun, a corresponding author of the study.
Beyond using cheap feedstock hydrocarbons as substrates, the team was also successful in converting amino acids, steroids, and other bio-relevant molecules into gamma-lactams, which might find a variety of applications as plant insecticide, drugs against parasitic worms, or anti-aging agents. This new synthetic technology gives much easier access to these complicated molecules and will enable the development of potential drugs in a much shorter amount of time at a lower cost.
Figure 1: Selective amidation reaction using newly designed iridium (Ir) catalysts. Abundant in nature Hydrocarbons are used as substrates to synthesize nitrogen-containing ring, called gamma-lactams.
Figure 2: Three possible reaction pathways and energy barriers predicted by computational chemistry. The scientists developed new iridium-based catalysts that are highly selective for the C–H insertion pathway which leads to the desired gamma-lactam molecules.
Figure 3: Interesting gamma-lactams derived from natural and unnatural amino acids, steroids, etc., which may be used to protect plants against insects, fight parasitic worms, or as anti-aging agents.
2018.03.02 View 8717 -
Samsung Electronics' Chairman Kwon Becomes the First Alumnus Honorary Doctorate
(Samsung Electronics' Chairman & CEO Kwon,left, and President Shin)
The semiconductor has bred innovation in Korea, as one of the staples of economic growth. Without the success of the semiconductor industry of Korea, it is hard to imagine the high tech dominance in the global market enjoyed by Korean companies.
It is said that one in every four Ph.D.s working in the semiconductor industry of Korea graduated from KAIST. Among them, Chairman and CEO Oh-Hyun Kwon of Samsung Electronics, Class of 1977, has arrived at the epitome of this top industry.
KAIST’s class of 1977 produced many movers and shakers in Korea’s innovation efforts. Now in their mid-60s, they were the players who embodied Korea’s ICT and helped it become a global powerhouse. They are the ones who worked for and witnessed the socio-economic transformation of Korea through innovation.
In recognition of his unsurpassable entrepreneurship, which made the remarkable strides in the semiconductor and electronics industry in Korea and beyond, Chairman Kwon was honored as the first recipient of an honorary doctorate from his alma mater on February 23 during the 2018 commencement ceremony.
After completing his Master's in Electrical Engineering at KAIST in 1977, he earned his Ph.D. in Electrical Engineering from Stanford University. The first honorary degree bestowed to an alumnus was conferred by the first alumnus President of KAIST Sung-Chul Shin. President Shin said that Chairman Kwon’s exceptional leadership has inspired the KAIST community and exemplified the spirit of KAIST.
Currently serving as chairman & CEO of Samsung Electronics and Samsung Advanced Institute of Technology (SAIT), Kwon has worked for Samsung in a variety of key positions in their semiconductor division since 1985.
In the mid-1980s, Japan was leading the global semiconductor market. At Samsung, Chairman Kwon, who was in charge of the memory semiconductor team, successfully developed 4M DRAM. Later in 1992, he played a leading role in the development of the world’s first 64M DRAM.
The success of 4M DRAM and 64M DRAM led Samsung to clinch the top position in the DRAM and NAND flash business around the world. This helped Samsung emerge as a global leader in the semiconductor industry.
As a result, Samsung, as well as the national economy, could gain significant momentum to build national competitiveness and economic growth. The outstanding technological leadership of Chairman Kwon led to the development of proprietary semiconductor design and processes technologies as well as numerous patents.
He also played a leadership role in creating a mutual growth environment among conglomerates rather than merely engaging in direct competition. Chairman Kwon made every effort to establish the cornerstone of mutual growth, especially in relationships with small and medium-sized enterprises (SMEs). His win-win collaboration initiatives among conglomerates and SMEs made a significant impact on the development of the entire industry of Korea.
In his acceptance speech, he charged the graduates to embrace challenges, to collaborate with peers, and create their own future.
The full text of his speech is printed below.
Graduates and distinguished guests! I extend my sincere congratulations to my fellow graduates, as you are awarded degrees for your deep efforts, as well as to the parents and family members who have supported you.
In 1977, I received my Master’s degree in Electrical Engineering from KAIST. Today, as the first honorary doctor among KAIST graduates, I am truly honored to be here. I am deeply grateful to all of you, including President Sung-Chul Shin and the Chairman of the Board of Trustees, Jang-Moo Lee.
Today, I want to tell you about the experiences and lessons I have learned from my 40 years of corporate management experience.
First, you should lead and drive changes by yourself. In the process of realizing a dream, the situation and circumstances do not always proceed as you planned.
I started my career as a researcher. However, I had to continuously transform myself into a project leader, business team leader, and CEO. It was challenging every time, due to a lack of preparing and my insufficient ability. However, I have always accomplished the intended goal through the mindset of embracing changes and studying new things.
It is said that the survivors are not always the strongest nor the most intelligent, but the ones who are the most adaptive to changes. We can only be the last survivor if we have the character to see those small signs that signal changes are coming and cope with changes well. Take changes positively and actively and then, transform yourself to match a given situation.
In addition, it is important to understand others. When it comes to one’s career, there is nothing that you can do alone without the assistance of others. If it is not possible to do everything by yourself, you will need to supplement your efforts through the help of others. To do this, you need to understand your colleagues, bosses, and customers first.
People, who work in tech tend to cage themselves in their own silos. But in an era of destructive innovation, where boundaries of industries and technologies are collapsing at a breakneck pace, scientists also need to enhance their understanding of various areas such as culture, art, and the humanities.
This is a famous verse from a poem by Chun-Soo Kim.
Before I called his name,
He was nothing but a gesture.
When I called his name, He came to me and became a flower.
Make wonderful synergy by making your partner a flower and complementing each other. When you first notice the true value of another person and interact with them, the value of the individual will be doubled and will bring about a greater impact.
Finally, we all need to cooperate with each other. All of you here, including myself, are people who have benefited from society. We must cooperate with each other and give back to society for the best results.
A biologist once said that incremental evolution comes from competition, but fundamental evolution comes from cooperation. Great leaders should achieve results through cooperation rather than competition.
You are the future leaders with top-class knowledge. I hope you will become great leaders who have wisdom that combines external resources with your abilities.
Now, graduates of 2018 who are standing at the starting line, we often worry about an unpredictable tomorrow. However, the smartest way to predict the future is to create the future for ourselves. Moreover, we can try again even though we sometimes make mistakes. I urge you to make future you are hoping for.
Once again, I would like to thank you for this honorary doctorate and extend my sincere wishes for the endless development of KAIST and the best of luck to the futures of these graduates. Thank you.
2018.02.26 View 8198 -
The 2018 Commencement of KAIST at a Glance
KAIST awarded a total of 2, 736 degrees at the 2018 commencement ceremony on February 23. Among the honorees, Chairman and CEO of Samsung Electronics and Samsung Advanced Institute of Technology (SAIT) Oh-Hyun Kwon was recognized as the first alumnus honorary doctorate recipient of KAIST.
More than 5,000 family, friends, and graduates including distinguished guests of Minister of Science and ICT Young-Min Yu, the Member of National Assembly Kyung-Jin Kim, Chairman of the KAIST Board of Trustees Jang-Moo Lee, and the Chairperson of the KAIST Development Foundation Soo-Young Lee attended to celebrate the graduates. During the commencement, a total of 2,736 students earned degrees: 644 PhD degrees, 1,352 master’s degrees, and 740 bachelor’s degrees.
(Minister of Science and ICT Young-Min Yu)
(The Member of National Assembly Kyung-Jin Kim)
This year, Chairman and CEO of Samsung Electronics and SAIT Kwon shared the spotlight with many other graduates. Kwon received his Master’s degree in Electrical Engineering from KAIST in 1977 and completed his Ph.D. in Electrical Engineering from Stanford University in 1985. During his more than 33-year career at Samsung, he has made significant contribution to the development of 4M DRAM and the world’s first 64M DRAM. The success of 4M DRAM and 64 DRAM led Samsung to clinch the top position in the DRAM and NAND flash business around the world. This helped Samsung emerge as a global leader in the semiconductor industry.
(From left: Chairman and CEO of Samsung Electronics and SAIT Oh-Hyun Kwon and KAIST President Sung-Chul Shin)
During the commencement speech, Kwon and President Shin both highlighted the importance of collaboration instead of competition.
Kwon encouraged the graduates to understand others to make wonderful synergy. “When you first notice the true value of another person and interact with them, the value of the individual will be doubled and will bring about a greater impact,” he said.
Also, he stressed having a collaborative mindset by saying, “All of you here, including myself, are people who have benefited from society. We must cooperate with each other and give back to society for the vest results.”
While highlighting the core values of KAIST, creativity, challenge and caring, President Shin also emphasized collaboration with others. He said, “In the future, expertise in a single discipline will not lead to new inventions or discoveries. This highlights the importance of multidisciplinary, convergence research. The key to success lies in the acknowledgement of your peers as partners for mutual growth. Your partners will make up your weak areas and become your most important asset. May you expand your personal network by finding valuable partners not only within your laboratory and workplace, but beyond Korea.”
“Go out into the world and change it as a global shaper, global innovator, and global mover. I hope that each and every one of you will add benefits the world and your legacy will be remembered for generations to come. This is your obligation as a graduate of KAIST,” he said.
Click here to view the full text of President Sung-Chul Shin’s address to the graduates
+ List of academically outstanding undergraduate degree recipients who received honors during the Commencement 2018 of KAIST
Award
Department
Winner
Minister of Science and ICT Award
Dept. of Mathematical Sciences
Seong-Hyeok Park
KAIST Board Chairperson Award
School of Computing
Hyeong-Seok Kim
KAIST President Award
Dept. of Chemistry
Hoi-Min Cheong
KAIST Development Foundation Chairperson Award
Dept. of Biological Sciences
Gi-Song Kim
Dept. of Industrial & Systems Engineering
Seung-Hun Lee
2018.02.23 View 11648 -
Professor Il-Doo Kim Recevies the Song-gok Award
Professor Il-Doo Kim from the Department of Materials Science and Engineering at KAIST received the 20th Song-gok Science and Technology Award from Korea Institute of Science and Technology (KSIT).
The Song-gok Science and Technology Award was established to praise the accomplishments of the first president, Hyung-seop Choi, whose penname is Song-gok. The award selects a recipient in the field of materials and technology every other year.
Professor Kim, in recognition of his outstanding research and contributions to materials science in Korea, received the award during the 52nd anniversary ceremony of KIST on February 9.
Professor Kim focuses on developing nanofiber gas sensors for diagnosing disease in advance by analyzing exhaled biomarkers with electrospinning technology.
He has published more than 211 papers and has recorded more than 9,650 citations and 50 h-index.
Professor Kim has registered 107 patents and applied 38 patents in Korea while registering 29 patents and applying 16 patents overseas. Also, he transferred four technologies in 2017.
Professor Kim is recognized as one of the researchers who is leading nanofiber technology. On January 17, he made a keynote speech at the 5th International Conference on Electrospinning, which was his fourth keynote speech at that conference.
Moreover, he received the Technology Innovation Award at the College of Engineering, KAIST on December 19, 2017.
Professor Kim said, “It is my great honor to receive the Song-gok Science and Technology Award. I would like to bring distinction to KAIST by taking the lead in the commercializing a nanofiber-based highly sensitive nanosensors, diversifying and commercializing technology using nanofiber.”
2018.02.13 View 8673 -
Finding Human Thermal Comfort with a Watch-type Sweat Rate Sensor
(from left: Professor Young-Ho Cho and Researcher SungHyun Yoon)
KAIST developed a watch-type sweat rate sensor. This subminiature device can detect human thermal comfort accurately and steadily by measuring an individual’s sweat rate.
It is natural to sweat more in the summer and less in the winter; however, an individual’s sweat rate may vary in a given environment. Therefore, sweat can be an excellent proxy for sensing core body temperature.
Conventional sweat rate sensors using natural ventilation require bulky external devices, such as pumps and ice condensers. They are usually for physiological experiments, hence they need a manual ventilation process or high power, bulky thermos-pneumatic actuators to lift sweat rate detection chambers above skin for continuous measurement. There is also a small sweat rate sensor, but it needs a long recovery period.
To overcome these problems, Professor Young-Ho Cho and his team from the Department of Bio and Brain Engineering developed a lightweight, watch-type sweat sensor. The team integrated miniaturized thermos-pneumatic actuators for automatic natural ventilation, which allows sweat to be measured continuously.
This watch-type sensor measures sweat rate with the humidity rising rate when the chamber is closed during skin contact. Since the team integrated thermos-pneumatic actuators, the chamber no longer needs to be separated manually from skin after each measurement in order for the chamber to ventilate the collected humidity.
Moreover, this sensor is wind-resistant enough to be used for portable and wearable devices. The team identified that the sensor operates steadily with air velocity ranging up to 1.5m/s, equivalent to the average human walking speed.
Although this subminiature sensor (35mm x 25mm) only weighs 30 grams, it operates continuously for more than four hours using the conventional wrist watch batteries.
The team plans to utilize this technology for developing a new concept of cognitive air-conditioning systems recognizing Human thermal status directly; while the conventional air-conditioning systems measuring air temperature and humidity.
Professor Cho said, “Our sensor for human thermal comfort monitoring can be applied to customized or smart air conditioners. Furthermore, there will be more demands for both physical and mental healthcare, hence this technology will serve as a new platform for personalized emotional communion between humans and devices.”
This research, led by researchers Jai Kyoung Sim and SungHyun Yoon, was published in Scientific Reports on January 19, 2018.
Figure1. The fabricated watch-type sweat rate sensor for human thermal comfort monitoring
Figure 2. Views of the watch-type sweat rate sensor
Figure 3. Operation of the watch-type sweat rate sensor
2018.02.08 View 8657 -
Structural Insight into the Molecular Mechanism of PET Degradation
A KAIST metabolic engineering research team has newly suggested a molecular mechanism showing superior degradability of poly ethylene terephthalate (PET).
This is the first report to simultaneously determine the 3D crystal structure of Ideonella sakaiensis PETase and develop the new variant with enhanced PET degradation.
Recently, diverse research projects are working to address the non-degradability of materials. A poly ethylene terephthalate (PET)-degrading bacterium called Ideonella sakaiensis was recently identified for the possible degradation and recycling of PET by Japanese team in Science journal (Yoshida et al., 2016). However, the detailed molecular mechanism of PET degradation has not been yet identified.
The team under Distinguished Professor Sang Yup Lee of the Department of Chemical and Biomolecular Engineering and the team under Professor Kyung-Jin Kim of the Department of Biotechnology at Kyungpook National University conducted this research. The findings were published in Nature Communications on January 26.
This research predicts a special molecular mechanism based on the docking simulation between PETase and a PET alternative mimic substrate. Furthermore, they succeeded in constructing the variant for IsPETase with enhanced PET-degrading activity using structural-based protein engineering.
It is expected that the new approaches taken in this research can be background for further study of other enzymes capable of degrading not only PET but other plastics as well.
PET is very important source in our daily lives. However, PET after use causes tremendous contamination issues to our environment due to its non-biodegradability, which has been a major advantage of PET. Conventionally, PET is disposed of in landfills, using incineration, and sometimes recycling using chemical methods, which induces additional environmental pollution. Therefore, a new development for highly-efficient PET degrading enzymes is essential to degrade PET using bio-based eco-friendly methods.
Recently, a new bacterial species, Ideonella sakaiensis, which can use PET as a carbon source, was isolated. The PETase of I. sakaiensis (IsPETase) can degrade PET with relatively higher success than other PET-degrading enzymes. However, the detailed enzyme mechanism has not been elucidated, hindering further studies.
The research teams investigated how the substrate binds to the enzyme and which differences in enzyme structure result in significantly higher PET degrading activity compared with other cutinases and esterases, which make IsPETase highly attractive for industrial applications toward PET waste recycling.
Based on the 3D structure and related biochemical studies, they successfully predicted the reasons for extraordinary PET degrading activity of IsPETase and suggested other enzymes that can degrade PET with a newly-classified phylogenetic tree. The team proposed that 4 MHET moieties are the most properly matched substrates due to a cleft on structure even with the 10-20-mers for PET. This is meaningful in that it is the first docking simulation between PETase and PET, not its monomer.
Furthermore, they succeeded in developing a new variant with much higher PET-degrading activity using a crystal structure of this variant to show that the changed structure is better to accommodate PET substrates than wild type PETase, which will lead to developing further superior enzymes and constructing platforms for microbial plastic recycling.
Professor Lee said, “Environmental pollution from plastics remains one of the greatest challenges worldwide with the increasing consumption of plastics. We successfully constructed a new superior PET-degrading variant with the determination of a crystal structure of PETase and its degrading molecular mechanism. This novel technology will help further studies to engineer more superior enzymes with high efficiency in degrading. This will be the subject of our team’s ongoing research projects to address the global environmental pollution problem for next generation.”
This work was supported by the Technology Development Program to Solve Climate Changes on Systems Metabolic Engineering for Biorefineries (NRF-2012M1A2A2026556 and NRF-2012M1A2A2026557) from the Ministry of Science and ICT through the National Research Foundation of Korea. Further Contact: Dr. Sang Yup Lee, Distinguished Professor, KAIST, Daejeon, Korea (leesy@kaist.ac.kr, +82-42-350-3930)
(Figure: Structural insight into the molecular mechanism of poly(ethylene terephthalate) degradation and the phylogenetic tree of possible PET degrading enzymes. This schematic diagram shows the overall conceptualization for structural insight into the molecular mechanism of poly (ethylene terephthalate) degradation and the phylogenetic tree of possible PET degrading enzymes.)
2018.01.31 View 9373