본문 바로가기
대메뉴 바로가기
KAIST
Newsletter Vol.25
Receive KAIST news by email!
View
Subscribe
Close
Type your e-mail address here.
Subscribe
Close
KAIST
NEWS
유틸열기
홈페이지 통합검색
-
검색
KOREAN
메뉴 열기
BIO
by recently order
by view order
Distinguished Professor Sang-Yup Lee received 2013 Amgen Biochemical Engineering Award
- Previous award winners are world-renowned scholars of biochemical engineering including James Bailey, Michael Shuler and Daniel Wang KAIST Chemical and Biomolecular Engineering Department’s Professor Sang-Yup Lee has been selected to receive the 2013 Amgen Biochemical Engineering Award. The award ceremony will take place this June at the International Biochemical and Molecular Engineering conference in Beijing, China. The Amgen Biochemical Engineering Award was established by Amgen, a world renowned American pharmaceutical company, in 1993. Amgen awards leading biochemical engineers every two years. The first Amgen award recipient was James Bailey of the California Institute of Technology (Caltech) in 1993. Since then leading engineers that are sometimes called “founding fathers of biochemical engineering” have received the award including MIT Professor Daniel Wang and Michael Shuler of Cornell University. The first nine award winners were Americans and in 2011 Jens Nielson of Chalmers University of Technology, Sweden, received the Amgen award as a non-American. Professor Sang-Yup Lee is the first Asian to receive the award. The Amgen award panel said, “Professor Lee made an incredible contribution to the fields of synthetic biology and industrial bioengineering by finding chemical material, fuel, protein and drug production and system bioengineering through metabolic engineering of microorganisms.” Professor Lee is an expert in metabolic engineering of microorganisms and contributed to the development of system metabolic engineering and system bioengineering. Furthermore, he developed various medical and chemical products and processes which were then applied to synthesise strains of succinate, plastics, butanol and nylon. Professor Lee is a fellow of the Korean Academy of Science and Technology and National Academy Engineering of Korea; an international member of National Academy of Engineering (US); a former fellow of the American Association for the Advancement of Science; a member of the American Institute of Chemical Engineers, the American Industrial Microbiology Society and American Academy of Microbiology. He is currently Head of Global Agenda Council on Biotechnology and is world renowned for his work in biotechnology field.
2013.04.30
View 8191
The new era of personalized cancer diagnosis and treatment
Professor Tae-Young Yoon - Succeeded in observing carcinogenic protein at the molecular level - “Paved the way to customized cancer treatment through accurate analysis of carcinogenic protein” The joint KAIST research team of Professor Tae Young Yoon of the Department of Physics and Professor Won Do Huh of the Department of Biological Sciences have developed the technology to monitor characteristics of carcinogenic protein in cancer tissue – for the first time in the world. The technology makes it possible to analyse the mechanism of cancer development through a small amount of carcinogenic protein from a cancer patient. Therefore, a personalised approach to diagnosis and treatment using the knowledge of the specific mechanism of cancer development in the patient may be possible in the future. Until recently, modern medicine could only speculate on the cause of cancer through statistics. Although developed countries, such as the United States, are known to use a large sequencing technology that analyses the patient’s DNA, identification of the interactions between proteins responsible for causing cancer remained an unanswered question for a long time in medicine. Firstly, Professor Yoon’s research team has developed a fluorescent microscope that can observe even a single molecule. Then, the “Immunoprecipitation method”, a technology to extract a specific protein exploiting the high affinity between antigens and antibodies was developed. Using this technology and the microscope, “Real-Time Single Molecule co-Immunoprecipitation Method” was created. In this way, the team succeeded in observing the interactions between carcinogenic and other proteins at a molecular level, in real time. To validate the developed technology, the team investigated Ras, a carcinogenic protein; its mutation statistically is known to cause around 30% of cancers. The experimental results confirmed that 30-50% of Ras protein was expressed in mouse tumour and human cancer cells. In normal cells, less than 5% of Ras protein was expressed. Thus, the experiment showed that unusual increase in activation of Ras protein induces cancer. The increase in the ratio of active Ras protein can be inferred from existing research data but the measurement of specific numerical data has never been done before. The team suggested a new molecular level diagnosis technique of identifying the progress of cancer in patients through measuring the percentage of activated carcinogenic protein in cancer tissue. Professor Yoon Tae-young said, “This newly developed technology does not require a separate procedure of protein expression or refining, hence the existing proteins in real biological tissues or cancer cells can be observed directly.” He also said, “Since carcinogenic protein can be analyzed accurately, it has opened up the path to customized cancer treatment in the future.” “Since the observation is possible on a molecular level, the technology confers the advantage that researchers can carry out various examinations on a small sample of the cancer patient.” He added, “The clinical trial will start in December 2012 and in a few years customized cancer diagnosis and treatment will be possible.” Meanwhile, the research has been published in Nature Communications (February 19). Many researchers from various fields have participated, regardless of the differences in their speciality, and successfully produced interdisciplinary research. Professor Tae Young Yoon of the Department of Physics and Professors Dae Sik Lim and Won Do Huh of Biological Sciences at KAIST, and Professor Chang Bong Hyun of Computational Science of KIAS contributed to developing the technique. Figure 1: Schematic diagram of observed interactions at the molecular level in real time using fluorescent microscope. The carcinogenic protein from a mouse tumour is fixed on the microchip, and its molecular characteristics are observed live. Figure 2: Molecular interaction data using a molecular level fluorescent microscope. A signal in the form of spike is shown when two proteins combine. This is monitored live using an Electron Multiplying Charge Coupled Device (EMCCD). It shows signal results in bright dots. An organism has an immune system as a defence mechanism to foreign intruders. The immune system is activated when unwanted pathogens or foreign protein are in the body. Antibodies form in recognition of the specific antigen to protect itself. Organisms evolved to form antibodies with high specificity to a certain antigen. Antibodies only react to its complementary antigens. The field of molecular biology uses the affinity between antigens and antibodies to extract specific proteins; a technology called immunoprecipitation. Even in a mixture of many proteins, the protein sought can be extracted using antibodies. Thus immunoprecipitation is widely used to detect pathogens or to extract specific proteins. Technology co-IP is a well-known example that uses immunoprecipitation. The research on interactions between proteins uses co-IP in general. The basis of fixing the antigen on the antibody to extract antigen protein is the same as immunoprecipitation. Then, researchers inject and observe its reaction with the partner protein to observe the interactions and precipitate the antibodies. If the reaction occurs, the partner protein will be found with the antibodies in the precipitations. If not, then the partner protein will not be found. This shows that the two proteins interact. However, the traditional co-IP can be used to infer the interactions between the two proteins although the information of the dynamics on how the reaction occurs is lost. To overcome these shortcomings, the Real-Time Single Molecule co-IP Method enables observation on individual protein level in real time. Therefore, the significance of the new technique is in making observation of interactions more direct and quantitative. Additional Figure 1: Comparison between Conventional co-IP and Real-Time Single Molecule co-IP
2013.04.01
View 17221
Ligand Recognition Mechanism of Protein Identified
Professor Hak-Sung Kim -“Solved the 50 year old mystery of how protein recognises and binds to ligands” - Exciting potential for understanding life phenomena and the further development of highly effective therapeutic agent development KAIST’s Biological Science Department’s Professor Hak-Sung Kim, working in collaboration with Professor Sung-Chul Hong of Department of Physics, Seoul National University, has identified the mechanism of how the protein recognizes and binds to ligands within the human body. The research findings were published in the online edition of Nature Chemical Biology (March 18), which is the most prestigious journal in the field of life science. Since the research identified the mechanism, of which protein recognises and binds to ligands, it will take an essential role in understanding complex life phenomenon by understanding regulatory function of protein. Also, ligand recognition of proteins is closely related to the cause of various diseases. Therefore the research team hopes to contribute to the development of highly effective treatments. Ligands, well-known examples include nucleic acid and proteins, form the structure of an organism or are essential constituents with special functions such as information signalling. In particular, the most important role of protein is recognising and binding to a particular ligand and hence regulating and maintaining life phenomena. The abnormal occurrence of an error in recognition of ligands may lead to various diseases. The research team focused on the repetition of change in protein structure from the most stable “open form” to a relatively unstable “partially closed form”. Professor Kim’s team analysed the change in protein structure when binding to a ligand on a molecular level in real time to explain the ligand recognition mechanism. The research findings showed that ligands prefer the most stable protein structure. The team was the first in the world to identify that ligands alter protein structure to the most stable, the lowest energy level, when it binds to the protein. In addition, the team found that ligands bind to unstable partially-closed forms to change protein structure. The existing models to explain ligand recognition mechanism of protein are “Induced Custom Model”, which involves change in protein structure in binding to ligands, and the “Structure Selection Model”, which argues that ligands select and recognise only the best protein structure out of many. The academic world considers that the team’s research findings have perfectly proved the models through experiments for the first time in the world. Professor Kim explained, “In the presence of ligands, there exists a phenomenon where the speed of altering protein structure is changed. This phenomenon is analysed on a molecular level to prove ligand recognition mechanism of protein for the first time”. He also said, “The 50-year old mystery, that existed only as a hypothesis on biology textbooks and was thought never to be solved, has been confirmed through experiments for the first time.” Figure 1: Proteins, with open and partially open form, recognising and binding to ligands. Figure 2: Ligands temporarily bind to a stable protein structure, open form, which changes into the most stable structure, closed form. In addition, binding to partially closed form also changes protein structure to closed form.
2013.04.01
View 10390
Top Ten Ways Biotechnology Could Improve Our Everyday Life
The Global Agenda Council on Biotechnology, one of the global networks under the World Economic Forum, which is composed of the world’s leading experts in the field of biotechnology, announced on February 25, 2013 that the council has indentified “ten most important biotechnologies” that could help meet rapidly growing demand for energy, food, nutrition, and health. These new technologies, the council said, also have the potential to increase productivity and create new jobs. “The technologies selected by the members of the Global Agenda Council on Biotechnology represent almost all types of biotechnology.Utilization of waste, personalized medicine,and ocean agricultureare examples of the challenges where biotechnology can offer solutions,”said Sang Yup Lee, Chair of the Global Agenda Council on Biotechnology and Distinguished Professor in the Department of Chemical and Biomolecular Engineering at the Korea Advanced Institute of Science and Technology (KAIST). He also added that “the members of the council concluded that regulatory certainty, public perception, and investment are the key enablers for the growth of biotechnology.” These ideas will be further explored during “Biotechnology Week” at the World Economic Forum’s Blog (http://wef.ch/blog) from Monday, 25 February, 2013. The full list follows below: Bio-based sustainable production of chemicals, energy, fuels and materials Through the last century, human activity has depleted approximately half of the world’s reserves of fossil hydrocarbons. These reserves, which took over 600 million years to accumulate, are non-renewable and their extraction, refining and use contribute significantly to human emissions of greenhouse gases and the warming of our planet. In order to sustain human development going forward, a carbon-neutral alternative must be implemented. The key promising technology is biological synthesis; that is, bio-based production of chemicals, fuels and materials from plants that can be re-grown. Engineering sustainable food production The continuing increase in our numbers and affluence are posing growing challenges to the ability of humanity to produce adequate food (as well as feed, and now fuel). Although controversial, modern genetic modification of crops has supported growth in agricultural productivity. In 2011, 16.7 million farmers grew biotechnology-developed crops on almost 400 million acres in 29 countries, 19 of which were developing countries. Properly managed, such crops have the potential to lower both pesticide use and tilling which erodes soil. Sea-water based bio-processes Over 70% of the earth surface is covered by seawater, and it is the most abundant water source available on the planet. But we are yet to discover the full potential of it. For example with halliophic bacteria capable of growing in the seawater can be engineered to grow faster and produce useful products including chemicals, fuels and polymeric materials. Ocean agriculture is also a promising technology. It is based on the photosynthetic biomass from the oceans, like macroalgae and microalgae. Non-resource draining zero waste bio-processing The sustainable goal of zero waste may become a reality with biotechnology. Waste streams can be processed at bio-refineries and turned into valuable chemicals and fuels, thereby closing the loop of production with no net waste. Advances in biotechnology are now allowing lower cost, less draining inputs to be used, including methane, and waste heat. These advances are simplifying waste streams with the potential to reduce toxicity as well as support their use in other processes, moving society progressively closer to the sustainable goal of zero waste. Using carbon dioxide as a raw material Biotechnology is poised to contribute solutions to mitigate the growing threat of rising CO2 levels. Recent advances are rapidly increasing our understanding of how living organisms consume and use CO2. By harnessing the power of these natural biological systems, scientists are engineering a new wave of approaches to convert waste CO2 and C1 molecules into energy, fuels, chemicals, and new materials. Regenerative medicine Regenerative medicine has become increasingly important due to both increased longevity and treatment of injury. Tissue engineering based on various bio-materials has been developed to speed up the regenerative medicine. Recently, stem cells, especially the induced pluripotent stem cells (iPS), have provided another great opportunity for regenerative medicine. Combination of tissue engineering and stem cell (including iPS) technologies will allow replacements of damaged or old human organs with functional ones in the near future. Rapid and precise development and manufacturing of medicine and vaccines A global pandemic remains one of the most real and serious threats to humanity. Biotechnology has the potential to rapidly identify biological threats, develop and manufacture potential cures. Leading edge biotechnology is now offering the potential to rapidly produce therapeutics and vaccines against virtually any target. These technologies, including messenger therapeutics, targeted immunotherapies, conjugated nanoparticles, and structure-based engineering, have already produced candidates with substantial potential to improve human health globally. Accurate, fast, cheap, and personalized diagnostics and prognostics Identification of better targets and combining nanotechnology and information technology it will be possible to develop rapid, accurate, personalized and inexpensive diagnostics and prognostics systems. Bio-tech improvements to soil and water Arable land and fresh water are two of the most important, yet limited, resources on earth. Abuse and mis-appropriation have threatened these resources, as the demand on them has increased. Advances in biotechnology have already yielded technologies that can restore the vitality and viability of these resources. A new generation of technologies: bio-remediation, bio-regeneration and bio-augmentation are being developed, offering the potential to not only further restore these resources, but also augment their potential. Advanced healthcare through genome sequencing It took more than 13 years and $1.5 billion to sequence the first human genome and today we can sequence a complete human genome in a single day for less than $1,000. When we analyze the roughly 3 billion base pairs in such a sequence we find that we differ from each other in several million of these base pairs. In the vast majority of cases these difference do not cause any issues but in rare cases they cause disease, or susceptibility to disease. Medical research and practice will increasingly be driven by our understanding of such genetic variations together with their phenotypic consequences.
2013.03.19
View 11025
An efficient strategy for developing microbial cell factories by employing synthetic small regulatory RNAs
A new metabolic engineering tool that allows fine control of gene expression level by employing synthetic small regulatory RNAs was developed to efficiently construct microbial cell factories producing desired chemicals and materials Biotechnologists have been working hard to address the climate change and limited fossil resource issues through the development of sustainable processes for the production of chemicals, fuels and materials from renewable non-food biomass. One promising sustainable technology is the use of microbial cell factories for the efficient production of desired chemicals and materials. When microorganisms are isolated from nature, the performance in producing our desired product is rather poor. That is why metabolic engineering is performed to improve the metabolic and cellular characteristics to achieve enhanced production of desired product at high yield and productivity. Since the performance of microbial cell factory is very important in lowering the overall production cost of the bioprocess, many different strategies and tools have been developed for the metabolic engineering of microorganisms. One of the big challenges in metabolic engineering is to find the best platform organism and to find those genes to be engineered so as to maximize the production efficiency of the desired chemical. Even Escherichia coli, the most widely utilized simple microorganism, has thousands of genes, the expression of which is highly regulated and interconnected to finely control cellular and metabolic activities. Thus, the complexity of cellular genetic interactions is beyond our intuition and thus it is very difficult to find effective target genes to engineer. Together with gene amplification strategy, gene knockout strategy has been an essential tool in metabolic engineering to redirect the pathway fluxes toward our desired product formation. However, experiment to engineer many genes can be rather difficult due to the time and effort required; for example, gene deletion experiment can take a few weeks depending on the microorganisms. Furthermore, as certain genes are essential or play important roles for the survival of a microorganism, gene knockout experiments cannot be performed. Even worse, there are many different microbial strains one can employ. There are more than 50 different E. coli strains that metabolic engineer can consider to use. Since gene knockout experiment is hard-coded (that is, one should repeat the gene knockout experiments for each strain), the result cannot be easily transferred from one strain to another. A paper published in Nature Biotechnology online today addresses this issue and suggests a new strategy for identifying gene targets to be knocked out or knocked down through the use of synthetic small RNA. A Korean research team led by Distinguished Professor Sang Yup Lee at the Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), a prestigeous science and engineering university in Korea reported that synthetic small RNA can be employed for finely controlling the expression levels of multiple genes at the translation level. Already well-known for their systems metabolic engineering strategies, Professor Lee’s team added one more strategy to efficiently develop microbial cell factories for the production of chemicals and materials. Gene expression works like this: the hard-coded blueprint (DNA) is transcribed into messenger RNA (mRNA), and the coding information in mRNA is read to produce protein by ribosomes. Conventional genetic engineering approaches have often targeted modification of the blueprint itself (DNA) to alter organism’s physiological characteristics. Again, engineering the blueprint itself takes much time and effort, and in addition, the results obtained cannot be transferred to another organism without repeating the whole set of experiments. This is why Professor Lee and his colleagues aimed at controlling the gene expression level at the translation stage through the use of synthetic small RNA. They created novel RNAs that can regulate the translation of multiple messenger RNAs (mRNA), and consequently varying the expression levels of multiple genes at the same time. Briefly, synthetic regulatory RNAs interrupt gene expression process from DNA to protein by destroying the messenger RNAs to different yet controllable extents. The advantages of taking this strategy of employing synthetic small regulatory RNAs include simple, easy and high-throughput identification of gene knockout or knockdown targets, fine control of gene expression levels, transferability to many different host strains, and possibility of identifying those gene targets that are essential. As proof-of-concept demonstration of the usefulness of this strategy, Professor Lee and his colleagues applied it to develop engineered E. coli strains capable of producing an aromatic amino acid tyrosine, which is used for stress symptom relief, food supplements, and precursor for many drugs. They examined a large number of genes in multiple E. coli strains, and developed a highly efficient tyrosine producer. Also, they were able to show that this strategy can be employed to an already metabolically engineered E. coli strain for further improvement by demonstrating the development of highly efficient producer of cadaverine, an important platform chemical for nylon in the chemical industry. This new strategy, being simple yet very powerful for systems metabolic engineering, is thus expected to facilitate the efficient development of microbial cell factories capable of producing chemicals, fuels and materials from renewable biomass. Source: Dokyun Na, Seung Min Yoo, Hannah Chung, Hyegwon Park, Jin Hwan Park, and Sang Yup Lee, “Metabolic engineering of Escherichia coli using synthetic small regulatory RNAs”, Nature Biotechnology, doi:10.1038/nbt.2461 (2013)
2013.03.19
View 9354
New BioFactory Technique Developed using sRNAs
Professor Sang Yup Lee - published on the online edition of Nature Biotechnology. “Expected as a new strategy for the bio industry that may replace the chemical industry.”- KAIST Chemical & Biomolecular engineering department’s Professor Sang Yup Lee and his team has developed a new technology that utilizes the synthetic small regulatory RNAs (sRNAs) to implement the BioFactory in a larger scale with more effectiveness. * BioFactory: Microbial-based production system which creates the desired compound in mass by manipulating the genes of the cell. In order to solve the problems of modern society, such as environmental pollution caused by the exhaustion of fossil fuels and usage of petrochemical products, an eco-friendly and sustainable bio industry is on the rise. BioFactory development technology has especially attracted the attention world-wide, with its ability to produce bio-energy, pharmaceuticals, eco-friendly materials and more. For the development of an excellent BioFactory, selection for the gene that produces the desired compounds must be accompanied by finding the microorganism with high production efficiency; however, the previous research method had a complicated and time-consuming problem of having to manipulate the genes of the microorganism one by one. Professor Sang Yup Lee’s research team, including Dr. Dokyun Na and Dr. Seung Min Yoo, has produced the synthetic sRNAs and utilized it to overcome the technical limitations mentioned above. In particular, unlike the existing method, this technology using synthetic sRNAs exhibits no strain specificity which can dramatically shorten the experiment that used to take months to just a few days. The research team applied the synthetic small regulatory RNA technology to the production of the tyrosine*, which is used as the precursor of the medicinal compound, and cadaverine**, widely utilized in a variety of petrochemical products, and has succeeded developing BioFactory with the world’s highest yield rate (21.9g /L, 12.6g / L each). *tyrosine: amino acid known to control stress and improve concentration **cadaverine: base material used in many petrochemical products, such as polyurethane Professor Sang Yup Lee highlighted the significance of this research: “it is expected the synthetic small regulatory RNA technology will stimulate the BioFactory development and also serve as a catalyst which can make the chemical industry, currently represented by its petroleum energy, transform into bio industry.” The study was carried out with the support of Global Frontier Project (Intelligent Bio-Systems Design and Synthesis Research Unit (Chief Seon Chang Kim)) and the findings have been published on January 20th in the online edition of the worldwide journal Nature Biotechnology.
2013.02.21
View 9967
High Efficiency Bio-butanol production technology developed
KAIST and Korean Company cooperative research team has developed the technology that increases the productivity of bio-butanol to equal that of bio-ethanol and decreases the cost of production. Professor Lee Sang Yeop (Department of Biological-Chemical Engineering) collaborated with GS Caltex and BioFuelChem Ltd. to develop a bio-butanol production process using the system metabolism engineering method that increased the productivity and decreased the production cost. Bio-butanol is being widely regarded as the environmentally friendly next generation energy source that surpasses bio-ethanol. The energy density of bio-butanol is 29.9MJ (mega Joule) per Liter, 48% larger than bio-ethanol (19.6MJ) and comparable to gasoline (32MJ). Bio-butanol is advantageous in that it can be processed from inedible biomass and is therefore unrelated to food crises. Especially because bio-butanol shows similar characteristics especially in its octane rating, enthalpy of vaporization, and air-fuel ratio, it can be used in a gasoline engine. However barriers such as difficulty in gene manipulation of producer bacterium and insufficient information prevented the mass production of bio-butanol. Professor Lee’s team applied the system metabolism engineering method that he had invented to shift the focus to the production pathway of bio-butanol and made a new metabolism model. In the new model the bio-butanol production pathway is divided into the hot channel and the cold channel. The research team focused on improving the efficiency of the hot channel and succeeded in improving the product yield of 49% (compared to theoretical yield) to 87%. The team furthered their research and developed a live bio-butanol collection and removal system with GS Caltex. The collaboration succeeded in producing 585g of butanol using 1.8kg of glucose at a rate of 1.3g per hour, boasting world’s highest concentration, productivity, and rate and improving productivity of fermentation by three fold and decreasing costs by 30%. The result of the research was published in world renowned ‘mBio’ microbiology journal.
2012.12.21
View 8551
Ph.D. students Hyowon Park and Won Ma receive Grand Prizes in Mathematics and Biology respectively.
Researchers in KAIST received best paper awards in two out of three fields at this year’s award ceremony for the “Second Annual Best Thesis Paper Award” held collectively by the Korea University Presidents’ Federation (with Chairman DaeSoon Lee) and the Korean Academy of Science and Technology (with Director GilSang Jung). Two researchers from KAIST, Hyowon Park (Department of Mathematics) and Won Ma (Department of Biology) received best paper awards. This prize, given by the both the Korea University Presidents’ Federation and the Korean Academy of Science and Technology since last year, is awarded to researchers and assistant professors who write the most outstanding thesis papers in the field of basic sciences. Park, who received the best paper award this year, did research on graph braid groups. He was supervised by Professor Kihyung Ko, who received the best supervisor reward. Ma, who received the best paper award in the field of biological science, researched about the Attention Deficit/Hyperactivity Disorder due to deficiency of the GIT1 synapse protein. His supervising professor also received the supervisor award. The award ceremony was held in the auditorium of the S-OIL headquarters in Seoul on November 30. Meanwhile, NASA researcher Jaehwa Lee received the best paper award in the field of earth science, and his supervising professor, Professor Jun Kim from Yonsei University who studies atmospheric science, received the best supervisor award.
2012.12.21
View 9567
Liver Damage Mechanism of Hepatitis C Proven
KAIST researchers found mechanics behind a Hepatitis C virus, thereby taking a step closer to the development of a cure for Hepatitis C. Professor Choi Chul Hui (Department of Biological and Brain Engineering) and Professor Shin Eui Chul (Graduate School of Medical Sciences) proved, for the first time in the world, the mechanism behind liver damage of a patient with Hepatitis C. It is anticipated that this discovery will allow for the development of a Hepatitis C cure that has no side effects and little Liver damage. Hepatitis C is an immune response of the body to the Hepatitis C virus and causes liver irritation. Around 170million people are infected with Hepatitis C worldwide including 1% of the Korean population. Once infected, most cases turn into chronic cases and may lead to liver cancer. However it was impossible to infect Hepatitis C within a test tube cell environment until 2005 and up till then Chimpanzees were used to study the virus which proved to be a huge barrier to research. The research team used cells infected with Hepatitis C virus and found out that the virus works by increasing the destruction of cells by the TNF-a protein responsible for the cell’s immune response. In addition the protein structure of the virus that causes this reaction was successfully found. Conventionally the Hepatitis C medication focused on the suppressing the growth of the virus and therefore had many side effects. The experimental results allow new medication aimed at suppressing the actual mechanism of liver damage to be discovered. The result was selected as the cover dissertation of the September Edition of the Hepatolog magazine.
2012.09.11
View 11499
KAIST researchers verify and control the mechanical properties of graphene
KAIST researchers have successfully verified and controlled the mechanical properties of graphene, a next-generation material. Professor Park Jung Yong from the EEWS Graduate School and Professor Kim Yong Hyun from the Graduate School of Nanoscience and Technology have succeeded in fluorinating a single atomic-layered graphene sample and controlling its frictional and adhesive properties. This is the first time the frictional properties of graphene have been examined at the atomic level, and the technology is expected to be applied to nano-sized robots and microscopic joints. Graphene is often dubbed “the dream material” because of its ability to conduct high amounts of electricity even when bent, making it the next-generation substitute for silicon semiconductors, paving the way for flexible display and wearable computer technologies. Graphene also has high potential applications in mechanical engineering because of its great material strength, but its mechanical properties remained elusive until now. Professor Park’s research team successfully produced individual graphene samples with fluorine-deficiency at the atomic level by placing the samples in Fluoro-xenon (XeF2) gas and applying heat. The surface of the graphene was scanned using a micro probe and a high vacuum atomic microscope to measure its dynamic properties. The research team found that the fluorinated graphene sample had 6 times more friction and 0.7 times more adhesiveness than the original graphene. Electrical measurements confirmed the fluorination process, and the analysis of the findings helped setup the theory of frictional changes in graphene. Professor Park stated that “graphene can be used for the lubrication of joints in nano-sized devices” and that this research has numerous applications such as the coating of graphene-based microdynamic devices. This research was published in the online June edition of Nano Letters and was supported by the Ministry of Science, Technology, and Education and the National Research Foundation as part of the World Class University (WCU) program.
2012.07.24
View 14228
Successful Development of Excavation System of Biomarkers containing Protein Decomposition Control Enzyme Information
A Korean team of researchers successfully developed a biomarker excavation system named E3Net that excavates biomarkers containing information of the enzymes that control the decomposition of proteins. The development of the system paved the possibility of development of new high quality biomarkers. *Biomarker: Molecular information of unique patterns derived from genes and proteins that allow the monitoring of physical changes from genetic or environmental causes. Professor Lee Kwan Soo’s team (Department of Biological Sciences) composed of Doctorate candidate Han Young Woong, Lee Ho Dong Ph.D. and Professor Park Jong Chul published a dissertation in the April edition of Molecular and Cellular Proteomics. (Dissertation Title: A system for exploring E3-mediated regulatory networks of cellular functions). Professor Lee’s team compiled all available information of the enzyme that controls protein decomposition (E3 enzyme) and successfully compiled the inter-substrate network by extracting information from 20,000 biology related data base dissertations. The result was the development of the E3Net system that analyzes the related cell function and disease. Cells have a system that produces, destroys, and recycles proteins in response to the ever changing environmental conditions. Error in these processes leads to disease. Therefore finding the relationship between E3 enzymes that control the decomposition of proteins and the substrates will allow disease curing and prevention to become much easier. E3 enzyme is responsible for 80% of the protein decomposition and is therefore predicted to be related to various diseases. However the information on E3 enzyme and inter-substrate behavior are spread out among numerous dissertations and data bases which prevented methodological analysis of the role of the related cells and characteristics of the disease itself. Professor Lee’s team was successful in creating the E3Net that compiled 2,201 pieces of E3 substrate information, 4,896 pieces of substrate information, and 1,671 pieces of inter-substrate relationship information. This compilation allows for the systematic analysis of cells and diseases. The newly created network is 10 times larger than the existing network and is the first case where it is possible to accurately find the cell function and related diseases. It is anticipated that the use of the E3Net will allow the excavation of new biomarkers for the development of personalized drug systems. The research team applied the E3Net to find tens of new candidate biomarkers related to the major modern diseases like diabetes and cancer.
2012.05.30
View 11789
Production of chemicals without petroleum
Systems metabolic engineering of microorganisms allows efficient production of natural and non-natural chemicals from renewable non-food biomass In our everyday life, we use gasoline, diesel, plastics, rubbers, and numerous chemicals that are derived from fossil oil through petrochemical refinery processes. However, this is not sustainable due to the limited nature of fossil resources. Furthermore, our world is facing problems associated with climate change and other environmental problems due to the increasing use of fossil resources. One solution to address above problems is the use of renewable non-food biomass for the production of chemicals, fuels and materials through biorefineries. Microorganisms are used as biocatalysts for converting biomass to the products of interest. However, when microorganisms are isolated from nature, their efficiencies of producing our desired chemicals and materials are rather low. Metabolic engineering is thus performed to improve cellular characteristics to desired levels. Over the last decade, much advances have been made in systems biology that allows system-wide characterization of cellular networks, both qualitatively and quantitatively, followed by whole-cell level engineering based on these findings. Furthermore, rapid advances in synthetic biology allow design and synthesis of fine controlled metabolic and gene regulatory circuits. The strategies and methods of systems biology and synthetic biology are rapidly integrated with metabolic engineering, thus resulting in "systems metabolic engineering". In the paper published online in Nature Chemical Biology on May 17, Professor Sang Yup Lee and his colleagues at the Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea present new general strategies of systems metabolic engineering for developing microorganisms for the production of natural and non-natural chemicals from renewable biomass. They first classified the chemicals to be produced into four categories based on whether they have thus far been identified to exist in nature (natural vs. nonnatural) and whether they can be produced by inherent pathways of microorganisms (inherent, noninherent, or created): natural-inherent, natural-noninherent, non-natural-noninherent, and non-natural-created ones. General strategies for systems metabolic engineering of microorganisms for the production of these chemicals using various tools and methods based on omics, genome-scale metabolic modeling and simulation, evolutionary engineering, synthetic biology are suggested with relevant examples. For the production of non-natural chemicals, strategies for the construction of synthetic metabolic pathways are also suggested. Having collected diverse tools and methods for systems metabolic engineering, authors also suggest how to use them and their possible limitations. Professor Sang Yup Lee said "It is expected that increasing number of chemicals and materials will be produced through biorefineries. We are now equipped with new strategies for developing microbial strains that can produce our desired products at very high efficiencies, thus allowing cost competitiveness to those produced by petrochemical refineries." Editor of Nature Chemical Biology, Dr. Catherine Goodman, said "It is exciting to see how quickly science is progressing in this field – ideas that used to be science fiction are taking shape in research labs and biorefineries. The article by Professor Lee and his colleagues not only highlights the most advanced techniques and strategies available, but offers critical advice to progress the field as a whole." The works of Professor Lee have been supported by the Advanced Biomass Center and Intelligent Synthetic Biology Center of Global Frontier Program from the Korean Ministry of Education, Science and Technology through National Research Foundation. Contact: Dr. Sang Yup Lee, Distinguished Professor and Dean, KAIST, Daejeon, Korea (leesy@kaist.ac.kr, +82-42-350-3930)
2012.05.23
View 11758
<<
첫번째페이지
<
이전 페이지
11
12
13
14
15
16
17
18
>
다음 페이지
>>
마지막 페이지 18