Earticle

KIST 강릉분원은 지난 40년간 KIST가 성취한 연구개발의 역량과 경험을 바탕 으로, 강원지역의 과학기술 발전에 기여하기 위하여 2006년도에 강릉 과학산업단지 내에 연구소 건설을 완료하였다. KIST 강릉분원은 대관령 지역의 천연물로부터 생리활성 물질 발굴, 동해안 지 역의 해양자원 개발, 그리고 지역의 환경 보전과 같이 강릉분원이 위치한 지역적 특 성을 반영한 연구개발 활동을 활발하게 전개하고 있다. 즉, 천연의약센터, 기능성천연 물센터 및 환경연구그룹 등으로 구성되어 있으며 구체적인 연구분야 및 내용은 다음 과 같다. 천연의약센터(Natural Medicine Center)에서는 국내 육상 및 해양생물자원으 로부터 항암, 항비만, 항치매 및 항염증과 같은 다양한 질병에 효능을 보이는 신규 천 연물 의약소재를 발굴하고 실용화시키는 연구를 진행하고 있으며 이를 위해 본 연구 소의 최신 연구장비와 의약학분야의 전문인력을 바탕으로 다양한 천연물을 대상으로 생체내외 활성을 탐색하여 약효가 탁월하고 부작용이 적은 소재를 발굴하고 다양한 동물모델을 이용한 인체적용 기능성 연구도 동시에 진행하고 있다. 이러한 연구를 통 해 선정된 유용 천연물 자원을 질병 치료 및 예방을 위한 천연의약으로 개발하기 위 하여 활성성분의 탐색, 분리 최적화, 화학적 구조분석 및 대량생산기법 연구를 하고 있다. 기능성천연물센터(Functional Food Center)는 천연물의 다양한 생리활성을 탐 색하여 유용천연물을 발굴하고, 천연물 화학 및 물리적 가공 연구법을 활용함으로써 궁극적으로 기능성 식품소재 개발을 목표로 하고 있다. 천연물에 전문화된 기기도입 및 시스템구축을 통한 천연물 유효성분의 탐색, 추출, 분리 및 구조결정, 천연물의 초 고속분석법을 연구하고 있으며, 이화학적 안정성이 낮은 천연의 유효성분들을 효율적 으로 추출하고 안정화시키기 위한 신개념의 물리적 가공기술을 통하여 기능성소재의 산업화를 위한 원천기술 개발을 추진하고 있다. 환경연구그룹은환경오염정화를위한소재및시스템개발을목적으로하는연구그룹으로 강원도지역의심각한오염원인수백개의폐광산정화를위해천연미네랄과폐기물을활용하여 경제적으로오염정화 를할수있는소재를개발하고오염현장에설치및가동할수있는시스템을 개발하며토양및지하수내에존재하는중금속, 유기오염물질을 동시에 제거할 수 있는 정 화물질도 개발하고 있다. 천연물, 환경분야에서 세계적 연구기관을 지향하고 있는 KIST강릉분원은 최신 의 연구정보를 교환하고 다양한 천연물 자원을 확보하기 위하여 세계 각국의 전문연 구기관들과 활발한 국제협력을 수행하고 있으며, 국내의 여러 관련 연구기관 및 대학, 기업 등과도 활발한 교류를 통해 글로벌 시장에서 우뚝 설 수 있는 세계적인 천연물 신약 및 기능성 식품 개발에 박차를 가하고 있다.

Human milk oligosaccharides (HMOs) have been proven to be a key ingredient found in breast milk and beneficial to infant health. Structurally, the fucose-containing oligosaccharides are major components, with a proportion of approximately 50–80% in the HMOs. In particular, 2-fucosyllactose (2’-FL) and 3-fucosyllactose (3-FL) are 2 major components of the abundant HMO component. Importantly, 2’-FL is approved for use in infant formula for improving probiotic functions by the FDA of the USA and the European Food Safety Authority, while 3-FL can be used as a prebiotic to improve the growth of beneficial microorganisms. Over the last decade, various approaches have been conducted for fucosyllactose (FL) production, including chemical synthesis, enzymatic conversion, and microbial fermentation. Most studies were performed in Escherichia coli due to the simple culture conditions and availability of various genetic tools. Besides E. coli, Bacillus subtilis and Saccharomyces cerevisiae have also been selected as the hosts for the production of FL due to their generally regarded safe (GRAS) status. As a type of GRAS strain, Corynebacterium glutamicum has been widely used in the biosynthesis of food-grade, high-value-added products, including lysine, glutamic acid, violacein and resveratrol. In this study, the biosynthetic enzymes of FL were condon-optimized and heterologously expressed in engineered C. glutamicum for the production of FL. The trace amount production of FL was confirmed by TLC, HPLC in this study.

Huntington’s disease (HD) is an autosomal dominant neurodegenerative disorder. The main cause of HD is assumed to be the mutation in the gene coding for huntingtin (Htt), and the mutated Htt contains an abnormally expanded polyglutamine stretch (polyQ>35), which tends to aggregate into insoluble amyloid-like fibrils. Many attempts were made to inhibit the polyglutamine-induced protein aggregation, and the non-reducing disaccharide trehalose was reported to alleviate the disease symptoms of HD transgenic mice. However, trehalose is known to be rapidly hydrolysed to glucose by trehalase enzyme present in the small intestine, and its uptake into tissues is regarded to be very low. In addition, there is no evidence that trehalose can cross the blood-brain barrier (BBB). Here we show that BBB-permeable trehalose derivatives could be prepared by applying the delivery methods which are previously developed before, and the derivatives were found to efficiently prevent the aggregation of polyQ in the transfected HEK293 cells. Furthermore, the derivative (TD-G6), when given ad libitum to a transgenic mouse model of HD (Tg R6/2), was found to significantly prolong lifespan, improve motor functions and reduce the inclusion bodies in the mouse brain compared with the trehalose control.

Polysaccharides from marine algae are known to exhibit various biological and pharmacological activities, including anticancer, immunostimulatory, anti-inflammatory, anti-coagulant, antioxidant, antibacterial, and antiviral activities, offering a variety of potential applications in the fields of foods, cosmetics, drug-delivery, tissue engineering and regenerative medicine, vaccines, and pharmaceutical industries. Sargassum horneri, which is a brown alga and abundantly grows along the coasts of Jeju island in South Korea, has anti-inflammatory, antioxidant and immnomodulatory activities. However, the anticancer effect against human colon cancer has not been revealed yet. We isolated polysaccharides from S. horneri (termed as SHP), analyzed the monosaccharides composition and molecular weight, and investigated the anticancer activity using human colon cancer cell line, HT-29 cells. Bio-LC and HPLC analysis showed that SHP mainly consists of fucose, galactose, and glucose with the molar ratios of 73.37, 17.61 and 9.02 mol%, and has molecular weight of approximately 122,153 and 14,170 kDa. SHP dose-dependently reduced cell viability on HT-29 and increased the cleavage of poly (ADP-ribose) polymerase(PARP) by approximately 10-fold compared to the untreated control group. Furthermore, SHP treatment decreased the procaspase-9, procaspase-8 and Bcl-2 protein expression by about 0.4, 0.7, and 0.3-fold compared to the untreated control group in HT-29 cells. Taken collectively, SHP is a mixture of high-molecular weight glucogalactofucan type polysaccharides and induces apoptotic cell death of human colon cancer cells via upregulation of the expression of apoptosis-related factors, suggesting that S. horneri-derived polysaccharides can be potent ingredients for health-beneficial foods or anti-cancer agents against human colon cancer.

(재)경기과학기술진흥원 경기바이오센터는 국내 생명공학분야의 효율적 육성과 연구개발을 위해 바이오/제약기술의 산업화 지원을 수행함으로 지역산업 고도화 및 국가경쟁력 강화에 기여하고자 설립되었으며, 道 내 바이오 기업의 연구개발을 전폭적으로 지원하여 신약, 세포 치료제, 바이오 신소재 개발을 돕고 기업의 가치와 경쟁력을 높여가고 있습니다. 이를 위해 Translation Research를 통하여 기초연구 성과의 산업화에 앞장서고 산․학․연 협 력의 시너지 효과를 극대화함으로서 기초연구 성과로부터 21세기 기업이 원하는 기술을 발 굴, 재가공하여 신기술의 실용화를 지원하고 있습니다. 또한, 첨단 인프라를 구축하고 전문 분석시험, Pilot, 단백질 위탁생산, HTS/HCS 스크리닝 등 전문서비스를 통해 기업의 기술상 용화 또한 적극 지원하고 있으며, 국내외 우수 연구기관과의 기술도입 ․ 이전 네트워크를 구 축하고 활발한 기술교류협력을 추진하고 있습니다. 본 세미나에서는 이러한 경기바이오센터 의 역할과 기능에 대하여 소개하고자 합니다.

Gastric cancer has one of the highest cancer mortality rates worldwide, largely because of di fficulties in early-stage detection. Aberrant glycosylation in serum proteins is related with many human diseases including inflammation and various types of cancer. Aberrant glycosylation is desirable in order to improve the specificity and sensitivity for clinical use. Here, we combined protein-specific immunoaffinity purification, glycan release, and MS analysis to examine haptoglobin glycosylation of gastric cancer patients for glyco-markers. Interestingly, abundances of several tri- and tetra-antennary fucosylated N-glycans were increased in gastric cancer patients. Additionally, structural analysis via LC/MS/MS demonstrated that the fucosylated complex type N-glycans were mainly decorated with antenna fucose. In this study, we developed a targeted glycoproteomic approach using chip-based nano LC-QTOF MS and MS/MS following antibody-assisted targeted purification to discover glycan signatures of serum haptoglobin for gastric cancer. We could further obtain a specific structure of fucosylated molecules that are potential glyco-markers for gastric cancer via LC/MS/MS. The current study demonstrates that glycomic profiling of targeted serum haptoglobin via LC/MS and LC/MS/MS may be used as a powerful platform to monitor the specific glycosylation associated with gastric cancer.

Ammonia-oxidizing archaea (AOA) from the phylum Thaumarchaeota are ubiquitous in marine ecosystems and play an important role in the carbon and nitrogen cycling. Although viruses are known to have a key impact on the functioning and mortality of their hosts, thereby regulating the global biogeochemical cycles, not a single virus infecting thaumarchaea has been isolated thus far. Here we report on the isolation and characterization of the Nitrosopumilus spindle-shaped viruses (NSV) which infect a marine AOA and are distinct from other known marine viruses. Their morphology, genome architecture and life cycle indicate that they are distantly related to spindle-shaped viruses infecting hyperthermophilic and hyperhalophilic archaea. However, NSVs do not share appreciable sequence similarity to other archaeal viruses, except for the protein-primed family B DNA polymerase, and are likely to represent a new virus family. NSVs have high adsorption rate to host cells and are not lytic. These properties might be important for the predation on chemolithoautotrophic hosts in resource-poor environments. We show that NSV infection results in cessation of ammonia oxidation, although host cells are not lysed. Widespread distribution of NSV in marine sediments indicates that viral predation regulates the diversity and dynamics in the AOA community.

N-glycosylation is a major post-translational protein modification, which alters physicochemical properties of the protein, affecting the folding, distribution, stability and thus biological function and efficiency of protein. Plant type complex N-glycans are distinctive from those found in mammalian because they contain β1,2-xylose and core α 1,3-fucose residues attached to the pentasaccharide (Man3GlcNAc2) core structure but no sialic acid residues. The presence of β1,2-xylose and core α1,3-fucose residues on plant type complex N-glycans has long been an irritating limitation in the use of plant-made pharmaceuticals (PMPs) in human therapy, as these N-glycan epitopes are potentially immunogenic in mammals. In this study, to remove the plant specific sugar residues and humanize the N-glycosylation in plant, we isolated mutants of the corresponding plant specific glycosyltransferase genes (α1,3-fucosyltransferase I, α1,3-fucosyltransferase II, β 1,2-xylosyltransferase, β1,3-galactosyltransferase and α1,4-fucosyltransferase). We made double, triple and quadruple mutants by crossing the mutants, and quintuple mutant is on the construction. The triple (fuct1/fuct2/xylt) and quadruple (fuct1/fuct2/xylt/fuct3) mutants do not show significant developmental defects in a normal growth condition and they do not produce the plant specific sugar residues on the N-glycan. The resulting mutant will be transformed by human α1,6-fucosyltransferase and β1,4-galactosyltransferase genes to accomplish further humanized N-glycosylation in plant. [Supported by BK21 program]

A diverse antibody repertoire in B cells is generated through the various processes such as V(D)J rearrangement, class switching recombination, and somatic hypermutation at the immunoglobulin(Ig) gene loci. During early B cell development, these Ig genes are initially assembled into functional transcription units by V(D)J rearrangement, a fundamental mechanism for antibody diversity. Several lymphoid-specific factors are recognized to be involved in these recombination processes which can facilitate long-distance interaction of Ig gene segments in germ-line DNA. Proteins within the nucleocytoplasmic compartment are dynamically modified by the addition of O-linked β-N-acetylglucosamine (O-GlcNAc), derived from the end-product uridine 5’-phosphate (UDP)-GlcNAc of the hexosamine biosynthetic pathway (HBP), to serine and threonine hydroxyl groups. Modifications by O-GlcNAcylation can modulate a protein function by altering stability, subcellular localization, protein–protein interaction, phosphorylation status and/or DNA binding ability. Despite the essential role of O-GlcNAcylation in regulating protein function, the linked mechanisms of O-GlcNAcylation and V(D)J recombination remain largely unknown. Here, we show that the long-range interaction in Ig gene loci spanning >3MB is defective during V(D)J recombination in B cells from bone marrow of mice administered with O-GlcNAc inhibitors. Restricted V(D)J recombination is similarly confirmed in a mouse model with nutritional deficiency induced by limiting calorie consumption to 50%. However, defected rearrangement is restored by applying the O-GlcNAc-inducible drugs even during caloric restriction. Significantly, several factors involved in V(D)J recombination such as YY1, SMC1, and SMC3, which can regulate long-range interactions by binding to various positions in the Ig gene loci, are identified as proteins directly modified by O-GlcNAcylation. In addition, DNA binding ability of these proteins is shown to be disrupted once O-GlcNAcylation is inhibited. These results unravel a previously unidentified link between O-GlcNAcylation and V(D)J rearrangement and potentially suggests a crucial role for O-GlcNAc signaling in representing nutritional state to affect antibody diversity.