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Krafton Matches Alumni Donations to Raise 11 Billion KRW for SW Developers
Alumni donations from the School of Computing, including Baemin and Devsisters, continue to grow Alumni from the KAIST School of Computing who are current and former developers at the leading game company Krafton, established by KAIST alumna Byung-Gyu Chang, made an agreement to help raise 11 billion KRW during a ceremony on June 4. The funds raised in the matching grant will be used to nurture software developers. Krafton Chairman Chang donated 10 billion won last January. His donation inspired other alumni working at Krafton as well as its former developers. Eleven KAIST alumni raised 5.5 billion KRW in two months and discussed the matching grant idea with Chairman Chang. The Krafton matching grant ceremony was attended by President Kwang Hyung Lee, Provost and Executive Vice President Seung Seob Lee, Vice President for Research Sang Yup Lee, Head of the School of Computing Sukyoung Ryu, Krafton Chairman Byung-gyu Chang, and KAIST alumnus from Krafton Seung-woo Shin. Other alumni donors including Krafton CEO Changhan Kim joined the ceremony online. Krafton CEO Changhan Kim said, “Just as our alma mater played an important role in growing our company, we hope that our donation could help support good developers. This will not only help our company, but advance our industry.” KAIST and Krafton also signed a business agreement to foster competitive developers. Krafton said it plans to continue giving back to society through the matching grant program. Head of the School of Computing Sukyoung Ryu thanked Chairman Chang and alumni who took part in the fund raising, saying, “To take the lead in rapidly changing computer technology, we desperately need more top students, faculty members, and facilities. We need more resources and infrastructure for interdisciplinary research.” The School of Computing has seen significant growth recently. Its number of undergraduate students has increased from 450 in 2016 to more than 900 in 2021. With this donation, the school will expand its current buildings to provide diverse educational and mentoring programs in more spacious facilities. Seung-woo Shin (Class of ’92), who joined Krafton’s matching grant, said, “I have always been thankful for the people I met and what I learned at KAIST. I was moved by the idea of giving back to the school.” Seong-jung Ryu (Class of ’97) said, “This donation reminded me of the good times I had back then. I thought it was crucial that the department’s facilities be extended, so I naturally wanted to take part.” Alumni donations, especially from the School of Computing, have also continued to grow more recently. Woowa Brothers Corp. CEO Beom-Jun Kim, the developer of the meal delivery app ‘Baemin’ donated 100 million KRW in April. Baemin became the most used app in the country during the COVID-19 pandemic. He explained, “I have been thinking about ways to give something to the next generation, rather than ‘paying back’ those who helped me in the past.” Encouraged by Baemin’s donation, alumni couple Ha-Yeon Seo and Dong-Hun Hahn from the School of Computing and eleven alumni engineers working at Devsisters Corp. also followed suit.
2021.06.09
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Ultrafast, on-Chip PCR Could Speed Up Diagnoses during Pandemics
A rapid point-of-care diagnostic plasmofluidic chip can deliver result in only 8 minutes Reverse transcription-polymerase chain reaction (RT-PCR) has been the gold standard for diagnosis during the COVID-19 pandemic. However, the PCR portion of the test requires bulky, expensive machines and takes about an hour to complete, making it difficult to quickly diagnose someone at a testing site. Now, researchers at KAIST have developed a plasmofluidic chip that can perform PCR in only about 8 minutes, which could speed up diagnoses during current and future pandemics. The rapid diagnosis of COVID-19 and other highly contagious viral diseases is important for timely medical care, quarantining and contact tracing. Currently, RT-PCR uses enzymes to reverse transcribe tiny amounts of viral RNA to DNA, and then amplifies the DNA so that it can be detected by a fluorescent probe. It is the most sensitive and reliable diagnostic method. But because the PCR portion of the test requires 30-40 cycles of heating and cooling in special machines, it takes about an hour to perform, and samples must typically be sent away to a lab, meaning that a patient usually has to wait a day or two to receive their diagnosis. Professor Ki-Hun Jeong at the Department of Bio and Brain Engineering and his colleagues wanted to develop a plasmofluidic PCR chip that could quickly heat and cool miniscule volumes of liquids, allowing accurate point-of-care diagnoses in a fraction of the time. The research was reported in ACS Nano on May 19. The researchers devised a postage stamp-sized polydimethylsiloxane chip with a microchamber array for the PCR reactions. When a drop of a sample is added to the chip, a vacuum pulls the liquid into the microchambers, which are positioned above glass nanopillars with gold nanoislands. Any microbubbles, which could interfere with the PCR reaction, diffuse out through an air-permeable wall. When a white LED is turned on beneath the chip, the gold nanoislands on the nanopillars quickly convert light to heat, and then rapidly cool when the light is switched off. The researchers tested the device on a piece of DNA containing a SARS-CoV-2 gene, accomplishing 40 heating and cooling cycles and fluorescence detection in only 5 minutes, with an additional 3 minutes for sample loading. The amplification efficiency was 91%, whereas a comparable conventional PCR process has an efficiency of 98%. With the reverse transcriptase step added prior to sample loading, the entire testing time with the new method could take 10-13 minutes, as opposed to about an hour for typical RT-PCR testing. The new device could provide many opportunities for rapid point-of-care diagnostics during a pandemic, the researchers say. -Publication Ultrafast and Real-Time Nanoplasmonic On-Chip Polymerase Chain Reaction for Rapid and Quantitative Molecular Diagnostics ACS Nano (https://doi.org/10.1021/acsnano.1c02154) -Professor Ki-Hun Jeong Biophotonics Laboratory https://biophotonics.kaist.ac.kr/ Department of Bio and Brain Engineeinrg KAIST
2021.06.08
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What Guides Habitual Seeking Behavior Explained
A new role of the ventral striatum explains habitual seeking behavior Researchers have been investigating how the brain controls habitual seeking behaviors such as addiction. A recent study by Professor Sue-Hyun Lee from the Department of Bio and Brain Engineering revealed that a long-term value memory maintained in the ventral striatum in the brain is a neural basis of our habitual seeking behavior. This research was conducted in collaboration with the research team lead by Professor Hyoung F. Kim from Seoul National University. Given that addictive behavior is deemed a habitual one, this research provides new insights for developing therapeutic interventions for addiction. Habitual seeking behavior involves strong stimulus responses, mostly rapid and automatic ones. The ventral striatum in the brain has been thought to be important for value learning and addictive behaviors. However, it was unclear if the ventral striatum processes and retains long-term memories that guide habitual seeking. Professor Lee’s team reported a new role of the human ventral striatum where long-term memory of high-valued objects are retained as a single representation and may be used to evaluate visual stimuli automatically to guide habitual behavior. “Our findings propose a role of the ventral striatum as a director that guides habitual behavior with the script of value information written in the past,” said Professor Lee. The research team investigated whether learned values were retained in the ventral striatum while the subjects passively viewed previously learned objects in the absence of any immediate outcome. Neural responses in the ventral striatum during the incidental perception of learned objects were examined using fMRI and single-unit recording. The study found significant value discrimination responses in the ventral striatum after learning and a retention period of several days. Moreover, the similarity of neural representations for good objects increased after learning, an outcome positively correlated with the habitual seeking response for good objects. “These findings suggest that the ventral striatum plays a role in automatic evaluations of objects based on the neural representation of positive values retained since learning, to guide habitual seeking behaviors,” explained Professor Lee. “We will fully investigate the function of different parts of the entire basal ganglia including the ventral striatum. We also expect that this understanding may lead to the development of better treatment for mental illnesses related to habitual behaviors or addiction problems.” This study, supported by the National Research Foundation of Korea, was reported at Nature Communications (https://doi.org/10.1038/s41467-021-22335-5.) -ProfileProfessor Sue-Hyun LeeDepartment of Bio and Brain EngineeringMemory and Cognition Laboratoryhttp://memory.kaist.ac.kr/lecture KAIST
2021.06.03
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KPC4IR Leads the Global Blockchain Standards Via Korea Innovation Studies
The Korea Policy Center for the Fourth Industrial Revolution (KPC4IR) at KAIST will play a leading role in the Global Standards Mapping Initiative (GSMI) 2.0 as the Chair of Working Group on South Korea at the Global Blockchain Business Council (GBBC). The GBBC, a Swiss-based non-profit consortium, established the GSMI to map blockchain technology ecosystem, established the GSMI to map blockchain and digital asset standards and regulation globally. The initial release of the GSMI mapped data and outputs from ons, 185 jurisdictions, nearly 400 industry groups, and over 30 technical standard-setting entities. The GSMI Working Group on South Korea is the only group that will investigate the country-level innovation of blockchain and digital asset alongside six Korean blockchain associations: The GSMI Working Group on South Korea is the only group that will investigate the country-level innovation of blockchain and digital asset alongside six Korean blockchain associations: the Korea Blockchain Association, the Korea Society of Blockchain, Blockchain & Law, the Open Blockchain and DID Association, the Korea Blockchain Startup Association, and the Korea Blockchain Industry Promotion Association. Individual members also joined from the Inter-American Development Bank, Blockchain Labs, and GOPAX. The GSMI Working Group on South Korea, chaired by KAIST, will leverage their experience in blockchain adoption to assist in setting global standards for the ecosystem. The Group will also highlight how South Korea can be a testbed for ITC adoption and open the door to a blockchain-ready world. GSMI 2.0 is spearheaded by nine working groups chaired by institutions, such as the World Economic Forum and the GBBC, Ernst & Young, HM Revenue and Customs, Accenture, and Hyperledger - Linux Foundation. Each of the Working Groups will be supported by sixteen fellows from eight fellow program partners. KAIST student Yujin Bang is the South Korea Working Group fellow. The GBBC and the WEF already published the first volume of the GSMI in October 2020 in collaboration with world-leading institutions, including KAIST, MIT Media Lab, and Accenture. Director of the KPC4IR Professor So Young Kim said, “The designation of KAIST is the result of continued collaborations with the WEF. The participation of this working group will help Korea’s global leadership with blockchain standards.”
2021.05.18
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Gut Hormone Triggers Craving for More Proteins
- Revelations from a fly study could improve our understanding of protein malnutrition in humans. - A new study led by KAIST researchers using fruit flies reveals how protein deficiency in the diet triggers cross talk between the gut and brain to induce a desire to eat foods rich in proteins or essential amino acids. This finding reported in the May 5 issue of Nature can lead to a better understanding of malnutrition in humans. “All organisms require a balanced intake of carbohydrates, proteins, and fats for their well being,” explained KAIST neuroscientist and professor Greg Seong-Bae Suh. “Taking in sufficient calories alone won’t do the job, as it can still lead to severe forms of malnutrition including kwashiorkor, if the diet does not include enough proteins,” he added. Scientists already knew that inadequate protein intake in organisms causes a preferential choice of foods rich in proteins or essential amino acids but they didn’t know precisely how this happens. A group of researchers led by Professor Suh at KAIST and Professor Won-Jae Lee at Seoul National University (SNU) investigated this process in flies by examining the effects of different genes on food preference following protein deprivation. The group found that protein deprivation triggered the release of a gut hormone called neuropeptide CNMamide (CNMa) from a specific population of enterocytes - the intestine lining cells. Until now, scientists have known that enterocytes release digestive enzymes into the intestine to help digest and absorb nutrients in the gut. “Our study showed that enterocytes have a more complex role than we previously thought,” said Professor Suh. Enterocytes respond to protein deprivation by releasing CNMa that conveys the nutrient status in the gut to the CNMa receptors on nerve cells in the brain. This then triggers a desire to eat foods containing essential amino acids. Interestingly, the KAIST-SNU team also found that the microbiome - Acetobacter bacteria - present in the gut produces amino acids that can compensate for mild protein deficit in the diet. This basal level of amino acids provided by the microbiome modifies CNMa release and tempers the flies’ compensatory desire to ingest more proteins. The research team was able to further clarify two signalling pathways that respond to protein loss from the diet and ultimately produce the CNMa hormone in these specific enterocytes. The team said that further studies are still needed to understand how CNMa communicates with its receptors in the brain, and whether this happens by directly activating nerve cells that link the gut to the brain or by indirectly activating the brain through blood circulation. Their research could provide insights into the understanding of similar process in mammals including humans. “We chose to investigate a simple organism, the fly, which would make it easier for us to identify and characterize key nutrient sensors. Because all organisms have cravings for needed nutrients, the nutrient sensors and their pathways we identified in flies would also be relevant to those in mammals. We believe that this research will greatly advance our understanding of the causes of metabolic disease and eating-related disorders,” Professor Suh added. This work was supported by the Samsung Science and Technology Foundation (SSTF) and the National Research Foundation (NRF) of Korea. Publication: Kim, B., et al. (2021) Response of the Drosophila microbiome– gut–brain axis to amino acid deficit. Nature. Available online at https://doi.org/10.1038/s41586-021-03522-2 Profile: Greg Seong-Bae Suh, Ph.D Associate Professor seongbaesuh@kaist.ac.krLab of Neural Interoception https://www.suhlab-neuralinteroception.kaist.ac.kr/Department of Biological Sciences https://bio.kaist.ac.kr/ Korea Advanced Institute of Science and Technology (KAIST) https:/kaist.ac.kr/en/ Daejeon 34141, Korea (END)
2021.05.17
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Observing Individual Atoms in 3D Nanomaterials and Their Surfaces
Atoms are the basic building blocks for all materials. To tailor functional properties, it is essential to accurately determine their atomic structures. KAIST researchers observed the 3D atomic structure of a nanoparticle at the atom level via neural network-assisted atomic electron tomography. Using a platinum nanoparticle as a model system, a research team led by Professor Yongsoo Yang demonstrated that an atomicity-based deep learning approach can reliably identify the 3D surface atomic structure with a precision of 15 picometers (only about 1/3 of a hydrogen atom’s radius). The atomic displacement, strain, and facet analysis revealed that the surface atomic structure and strain are related to both the shape of the nanoparticle and the particle-substrate interface. Combined with quantum mechanical calculations such as density functional theory, the ability to precisely identify surface atomic structure will serve as a powerful key for understanding catalytic performance and oxidation effect. “We solved the problem of determining the 3D surface atomic structure of nanomaterials in a reliable manner. It has been difficult to accurately measure the surface atomic structures due to the ‘missing wedge problem’ in electron tomography, which arises from geometrical limitations, allowing only part of a full tomographic angular range to be measured. We resolved the problem using a deep learning-based approach,” explained Professor Yang. The missing wedge problem results in elongation and ringing artifacts, negatively affecting the accuracy of the atomic structure determined from the tomogram, especially for identifying the surface structures. The missing wedge problem has been the main roadblock for the precise determination of the 3D surface atomic structures of nanomaterials. The team used atomic electron tomography (AET), which is basically a very high-resolution CT scan for nanomaterials using transmission electron microscopes. AET allows individual atom level 3D atomic structural determination. “The main idea behind this deep learning-based approach is atomicity—the fact that all matter is composed of atoms. This means that true atomic resolution electron tomogram should only contain sharp 3D atomic potentials convolved with the electron beam profile,” said Professor Yang. “A deep neural network can be trained using simulated tomograms that suffer from missing wedges as inputs, and the ground truth 3D atomic volumes as targets. The trained deep learning network effectively augments the imperfect tomograms and removes the artifacts resulting from the missing wedge problem.” The precision of 3D atomic structure can be enhanced by nearly 70% by applying the deep learning-based augmentation. The accuracy of surface atom identification was also significantly improved. Structure-property relationships of functional nanomaterials, especially the ones that strongly depend on the surface structures, such as catalytic properties for fuel-cell applications, can now be revealed at one of the most fundamental scales: the atomic scale. Professor Yang concluded, “We would like to fully map out the 3D atomic structure with higher precision and better elemental specificity. And not being limited to atomic structures, we aim to measure the physical, chemical, and functional properties of nanomaterials at the 3D atomic scale by further advancing electron tomography techniques.” This research, reported at Nature Communications, was funded by the National Research Foundation of Korea and the KAIST Global Singularity Research M3I3 Project. -Publication Juhyeok Lee, Chaehwa Jeong & Yongsoo Yang “Single-atom level determination of 3-dimensional surface atomic structure via neural network-assisted atomic electron tomography” Nature Communications -Profile Professor Yongsoo Yang Department of Physics Multi-Dimensional Atomic Imaging Lab (MDAIL) http://mdail.kaist.ac.kr KAIST
2021.05.12
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Prof. Sang Yup Lee Elected as a Foreign Member of the Royal Society
Vice President for Research Distinguished Professor Sang Yup Lee was elected as a foreign member of the Royal Society in the UK. On May 6, the Society announced the list of distinguished new 52 fellows and 10 foreign members who achieved exceptional contributions to science. Professor Lee and Professor V. Narry Kim from Seoul National University are the first foreign members ever elected from Korea. The Royal Society, established in 1660, is one of the most prestigious national science academies and a fellowship of 1,600 of the world’s most eminent scientists. From Newton to Darwin, Einstein, Hawking, and beyond, pioneers and paragons in their fields are elected by their peers. To date, there are 280 Nobel prize winners among the fellows. Distinguished Professor Lee from the Department of Chemical and Biomolecular Engineering at KAIST is one of the Highly Cited Researchers (HCRs) who pioneered systems metabolic engineering and developed various micro-organisms for producing a wide range of fuels, chemicals, materials, and natural compounds. His seminal scholarship and research career have already been recognized worldwide. He is the first Korean ever elected into the National Academy of Inventors (NAI) in the US and one of 13 scholars elected as an International Member of both the National Academy of Sciences (NAS) and the National Academy of Engineering (NAE) in the US. With this fellowship, he added one more accolade of being the first non-US and British Commonwealth scientist elected into the three most prestigious science academies: the NAS, the NAE, and the Royal Society.
2021.05.07
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Professor Byungha Shin Named Scientist of the Month
Professor Byungha Shin from the Department of Materials Science and Engineering won the Scientist of the Month Award presented by the Ministry of Science and ICT (MSIT) and the National Research Foundation of Korea (NRF) on May 4. Professor Shin was recognized for his research in the field of next-generation perovskite solar cells and received 10 million won in prize money. To achieve ‘carbon neutrality,’ which many countries across the globe including Korea hope to realize, the efficiency of converting renewable energies to electricity must be improved. Solar cells convert solar energy to electricity. Since single solar cells show lower efficiency, the development of ‘tandem solar cells’ that connect two or more cells together has been popular in recent years. However, although ‘perovskite’ received attention as a next-generation material for tandem solar cells, it is sensitive to the external environment including light and moisture, making it difficult to maintain stability. Professor Shin discovered that, theoretically, adding certain anion additives to perovskite solar cells would allow the control of the electrical and structural properties of the two-dimensional stabilization layer that forms inside the film. He confirmed this through high-resolution transmission electron microscopy. Controlling the amount of anions in the additives allowed the preservation of over 80% of the initial stability even after 1000 hours of continuous exposure to sunlight. Based on this discovery, Professor Shin combined silicon with solar cells to create a tandem solar cell with 26.7% energy convergence efficiency. Considering that the highest-efficiency tandem solar cell in existence showed 29.5% efficiency, this figure is quite high. Professor Shin’s perovskite solar cell is also combinable with the CIGS (Cu(In,Ga)Se2) thin-film solar cell composed of copper (Cu), indium (In), gallium (Ga), and selenium (Se2). Professor Shin’s research results were published in the online edition of the journal Science in April of last year. “This research is meaningful for having suggested a direction for solar cell material stabilization using additives,” said Professor Shin. “I look forward to this technique being applied to a wide range of photoelectrical devices including solar cells, LEDs, and photodetectors,” he added. (END)
2021.05.07
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KAIST Teams Up with Yozma Group to Nurture Startups
KAIST has joined hands with Israeli venture capital investor Yozma Group to help campus-based startups grow and build success. The two signed a memorandum of understanding (MOU) on joint technology value creation initiatives at the signing ceremony that was held at KAIST’s main campus in Daejeon on April 8. Under the MOU, Yozma Group will make investments and implement acceleration programs for startups established by KAIST professors, graduates, and students, as well as those invested in by the university. Yozma Group already launched a $70 million fund to help grow companies in Korea and Israel. Yozma Group will use the fund as well as its global acceleration know-how and network of over 400 R&D centers across Israel to help promising KAIST startups enter overseas markets. Moreover, Yozma Group also plans to discover and support KAIST startups that need technology from the Weizmann Institute of Science, Israel’s leading multidisciplinary basic research institution in natural and exact sciences. KAIST is also in talks to locate Yozma Group’s branch office on the university’s campus to ensure seamless collaborations. KAIST President Kwang Hyung Lee explained to Yozma Group’s Founder and Chairman Yigal Erlich and Head of Asia Pacific Won-Jae Lee at the MOU signing ceremony that “startup and technology commercialization are the crucial areas where KAIST will make innovations.” “Cooperation with Yozma Group will help KAIST startups transform their ideas and technologies into real businesses and build a global presence,” he added. Yozma Group started as Yozma Fund, created in conjunction with the Israeli government in 1993 to support the globalization of Israeli startups and to foster the growth of Israel’s venture capital industry. The Fund, which was privatized in 1998, has supported 97 Israeli tech ventures joining the Nasdaq, leading Israel to become a global innovation hub that has the third-most companies listed on the Nasdaq. (END)
2021.04.20
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COVID-Update: KAIST on High Alert amid Spring Resurgence
COVID-19 Task Force responds 24-7 and ISSS provides returning international students with a comfort package during 14-day mandatory quarantine In response to the upsurge of COVID-19 cases in the proximate college districts in Daejeon, KAIST announced the enforcement of stricter health and safety regulations. Korean health authorities expected another surge of COVID-19 cases this spring as Korea’s daily new COVID-19 cases have rebounded to the high 600s and over 700 in April, which is the most in over three months. New guidelines issued on April 5 banned faculty, staff, and students from engaging in off-campus activities and utilizing external public facilities. Such facilities include, but are not limited to, bars, cafes, clubs, gyms, karaoke rooms, PC rooms, restaurants, and other crowded indoor spaces. All class and research activities, work meetings, and school events were moved exclusively online, and working from home and flexible working hours were highly encouraged in order to minimize face-to-face interactions on campus. In particular, having meals outside of KAIST cafeterias in groups of two or more was prohibited, while food delivery and take-outs were allowed. Executive Vice President and Provost Seung Seob Lee said in a letter to the KAIST community on April 5 that “the school considers the risk of the current situation to be very high, likely the highest since the outbreak of COVID-19.” Provost Lee then called for more team efforts to contain the current phase of the pandemic and asked everyone to do their part. The school installed new temperature scanners equipped with hand sanitizer dispensers in front of the dormitory entrances to further control the spread of the disease on campus, following confirmed COVID-19 cases among dormitory residents. As the COVID-19 pandemic continues with no clear end in sight, the Task Force for the Prevention of COVID-19 and the International Scholar and Student Services (ISSS) Team at KAIST are working around the clock to reduce the risk of infection spread not only within the campus, but also coming from outside the campus. Under strict health and safety guidelines, KAIST has allowed international students to come back to campus. Currently about 600 international students, mostly graduate students reside on campus. All returning students should complete the mandatory 14-day self-quarantine required by the Korean government at their own expense. The KAIST COVID-19 Task Force is in charge of enacting on-campus health and safety guidelines, responding to reports and inquiries from the KAIST community 24-7, and controlling outsider access, among other responsibilities. The ISSS Team requires returning international students to fill out an entry authorization form and receive approval from the KAIST COVID-19 Task Force prior to returning to campus from their home countries. Once students arrive at their designated quarantine facility, the KAIST ISSS Team sends care packages, which includes some toiletries, instant food, a multipot, a thermometer, and other daily necessities. During the quarantine period, returning students are also advised to follow the directions given by government officials and to coordinate with the ISSS Team. The team also provides useful Korean phrases for international students to help them with communication. The self-quarantine period ends at 12 p.m. 14 days after arrival. Within two days of finishing the 14 days of self-isolation, these students are required to undergo a polymerase chain reaction (PCR) test for COVID-19 at the nearest health center. After confirmed negative, they are allowed to move into on-campus accommodations. KAIST will maintain the current method of remote education and distancing methods until further notice. (END)
2021.04.16
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Microbial Production of a Natural Red Colorant Carminic Acid
Metabolic engineering and computer-simulated enzyme engineering led to the production of carminic acid, a natural red colorant, from bacteria for the first time A research group at KAIST has engineered a bacterium capable of producing a natural red colorant, carminic acid, which is widely used for food and cosmetics. The research team reported the complete biosynthesis of carminic acid from glucose in engineered Escherichia coli. The strategies will be useful for the design and construction of biosynthetic pathways involving unknown enzymes and consequently the production of diverse industrially important natural products for the food, pharmaceutical, and cosmetic industries. Carminic acid is a natural red colorant widely being used for products such as strawberry milk and lipstick. However, carminic acid has been produced by farming cochineals, a scale insect which only grows in the region around Peru and Canary Islands, followed by complicated multi-step purification processes. Moreover, carminic acid often contains protein contaminants that cause allergies so many people are unwilling to consume products made of insect-driven colorants. On that account, manufacturers around the world are using alternative red colorants despite the fact that carminic acid is one of the most stable natural red colorants. These challenges inspired the metabolic engineering research group at KAIST to address this issue. Its members include postdoctoral researchers Dongsoo Yang and Woo Dae Jang, and Distinguished Professor Sang Yup Lee of the Department of Chemical and Biomolecular Engineering. This study entitled “Production of carminic acid by metabolically engineered Escherichia coli” was published online in the Journal of the American Chemical Society (JACS) on April 2. This research reports for the first time the development of a bacterial strain capable of producing carminic acid from glucose via metabolic engineering and computer simulation-assisted enzyme engineering. The research group optimized the type II polyketide synthase machinery to efficiently produce the precursor of carminic acid, flavokermesic acid. Since the enzymes responsible for the remaining two reactions were neither discovered nor functional, biochemical reaction analysis was performed to identify enzymes that can convert flavokermesic acid into carminic acid. Then, homology modeling and docking simulations were performed to enhance the activities of the two identified enzymes. The team could confirm that the final engineered strain could produce carminic acid directly from glucose. The C-glucosyltransferase developed in this study was found to be generally applicable for other natural products as showcased by the successful production of an additional product, aloesin, which is found in aloe leaves. “The most important part of this research is that unknown enzymes for the production of target natural products were identified and improved by biochemical reaction analyses and computer simulation-assisted enzyme engineering,” says Dr. Dongsoo Yang. He explained the development of a generally applicable C-glucosyltransferase is also useful since C-glucosylation is a relatively unexplored reaction in bacteria including Escherichia coli. Using the C-glucosyltransferase developed in this study, both carminic acid and aloesin were successfully produced from glucose. “A sustainable and insect-free method of producing carminic acid was achieved for the first time in this study. Unknown or inefficient enzymes have always been a major problem in natural product biosynthesis, and here we suggest one effective solution for solving this problem. As maintaining good health in the aging society is becoming increasingly important, we expect that the technology and strategies developed here will play pivotal roles in producing other valuable natural products of medical or nutritional importance,” said Distinguished Professor Sang Yup Lee. This work was supported by the Technology Development Program to Solve Climate Changes on Systems Metabolic Engineering for Biorefineries of the Ministry of Science and ICT (MSIT) through the National Research Foundation (NRF) of Korea and the KAIST Cross-Generation Collaborative Lab project; Sang Yup Lee and Dongsoo Yang were also supported by Novo Nordisk Foundation in Denmark. Publication: Dongsoo Yang, Woo Dae Jang, and Sang Yup Lee. Production of carminic acid by metabolically engineered Escherichia coli. at the Journal of the American Chemical Society. https://doi.org.10.1021/jacs.0c12406 Profile: Sang Yup Lee, PhD Distinguished Professor leesy@kaist.ac.kr http://mbel.kaist.ac.kr Metabolic &Biomolecular Engineering National Research Laboratory Department of Chemical and Biomolecular Engineering KAIST
2021.04.06
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Streamlining the Process of Materials Discovery
The materials platform M3I3 reduces the time for materials discovery by reverse engineering future materials using multiscale/multimodal imaging and machine learning of the processing-structure-properties relationship Developing new materials and novel processes has continued to change the world. The M3I3 Initiative at KAIST has led to new insights into advancing materials development by implementing breakthroughs in materials imaging that have created a paradigm shift in the discovery of materials. The Initiative features the multiscale modeling and imaging of structure and property relationships and materials hierarchies combined with the latest material-processing data. The research team led by Professor Seungbum Hong analyzed the materials research projects reported by leading global institutes and research groups, and derived a quantitative model using machine learning with a scientific interpretation. This process embodies the research goal of the M3I3: Materials and Molecular Modeling, Imaging, Informatics and Integration. The researchers discussed the role of multiscale materials and molecular imaging combined with machine learning and also presented a future outlook for developments and the major challenges of M3I3. By building this model, the research team envisions creating desired sets of properties for materials and obtaining the optimum processing recipes to synthesize them. “The development of various microscopy and diffraction tools with the ability to map the structure, property, and performance of materials at multiscale levels and in real time enabled us to think that materials imaging could radically accelerate materials discovery and development,” says Professor Hong. “We plan to build an M3I3 repository of searchable structural and property maps using FAIR (Findable, Accessible, Interoperable, and Reusable) principles to standardize best practices as well as streamline the training of early career researchers.” One of the examples that shows the power of structure-property imaging at the nanoscale is the development of future materials for emerging nonvolatile memory devices. Specifically, the research team focused on microscopy using photons, electrons, and physical probes on the multiscale structural hierarchy, as well as structure-property relationships to enhance the performance of memory devices. “M3I3 is an algorithm for performing the reverse engineering of future materials. Reverse engineering starts by analyzing the structure and composition of cutting-edge materials or products. Once the research team determines the performance of our targeted future materials, we need to know the candidate structures and compositions for producing the future materials.” The research team has built a data-driven experimental design based on traditional NCM (nickel, cobalt, and manganese) cathode materials. With this, the research team expanded their future direction for achieving even higher discharge capacity, which can be realized via Li-rich cathodes. However, one of the major challenges was the limitation of available data that describes the Li-rich cathode properties. To mitigate this problem, the researchers proposed two solutions: First, they should build a machine-learning-guided data generator for data augmentation. Second, they would use a machine-learning method based on ‘transfer learning.’ Since the NCM cathode database shares a common feature with a Li-rich cathode, one could consider repurposing the NCM trained model for assisting the Li-rich prediction. With the pretrained model and transfer learning, the team expects to achieve outstanding predictions for Li-rich cathodes even with the small data set. With advances in experimental imaging and the availability of well-resolved information and big data, along with significant advances in high-performance computing and a worldwide thrust toward a general, collaborative, integrative, and on-demand research platform, there is a clear confluence in the required capabilities of advancing the M3I3 Initiative. Professor Hong said, “Once we succeed in using the inverse “property−structure−processing” solver to develop cathode, anode, electrolyte, and membrane materials for high energy density Li-ion batteries, we will expand our scope of materials to battery/fuel cells, aerospace, automobiles, food, medicine, and cosmetic materials.” The review was published in ACS Nano in March. This study was conducted through collaborations with Dr. Chi Hao Liow, Professor Jong Min Yuk, Professor Hye Ryung Byon, Professor Yongsoo Yang, Professor EunAe Cho, Professor Pyuck-Pa Choi, and Professor Hyuck Mo Lee at KAIST, Professor Joshua C. Agar at Lehigh University, Dr. Sergei V. Kalinin at Oak Ridge National Laboratory, Professor Peter W. Voorhees at Northwestern University, and Professor Peter Littlewood at the University of Chicago (Article title: Reducing Time to Discovery: Materials and Molecular Modeling, Imaging, Informatics, and Integration).This work was supported by the KAIST Global Singularity Research Program for 2019 and 2020. Publication: “Reducing Time to Discovery: Materials and Molecular Modeling, Imaging, Informatics and Integration,” S. Hong, C. H. Liow, J. M. Yuk, H. R. Byon, Y. Yang, E. Cho, J. Yeom, G. Park, H. Kang, S. Kim, Y. Shim, M. Na, C. Jeong, G. Hwang, H. Kim, H. Kim, S. Eom, S. Cho, H. Jun, Y. Lee, A. Baucour, K. Bang, M. Kim, S. Yun, J. Ryu, Y. Han, A. Jetybayeva, P.-P. Choi, J. C. Agar, S. V. Kalinin, P. W. Voorhees, P. Littlewood, and H. M. Lee, ACS Nano 15, 3, 3971–3995 (2021) https://doi.org/10.1021/acsnano.1c00211 Profile: Seungbum Hong, PhD Associate Professor seungbum@kaist.ac.kr http://mii.kaist.ac.kr Department of Materials Science and Engineering KAIST (END)
2021.04.05
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