Publications by authors named "Junggyu Lee"

To investigate the relationship between muscle fiber characteristics and meat quality traits by age of Korean native black goat (KNBG), four muscles (, LD; , PM; , SM; , GM) were obtained from five adult goat (AG; 18 months old) and five young goat (YG; 9 months old). PM muscle had the highest fiber number percentage (FNP) and fiber area percentage (FAP) of type I, followed by SM, GM, and LD muscles. FNP and FAP of type IIB were significantly (p<0.

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This study assessed the effects of non-stunning (NS) and head-only electrical stunning (HOES) slaughtering condition on meat quality traits of (LL) muscle from Korean black goat (KBG). Ten KBGs (18 months) were assigned into two groups and exposed to either NS or HOES treatments. Blood loss (BL) % was measured after exsanguination, and meat quality traits including muscle pH, meat color measurements (CIE L*, a*, b*, Chroma, and hue angle), water-holding capacity (WHC), Warner-Bratzler shear force (WBSF), and sarcomere length were measured at 24 h postmortem.

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The aim of this study was to determine meat quality characteristics and fatty acid composition of Korean native black goats (KNBG) finished on intensive feeding of alfalfa (ALF) and conventional feeding of commercial concentrate pellets (CCP) with low-energy common grasses. Ten KNBG (12 months old) were divided into two groups and subjected to either ALF or CCP treatments. The goats were slaughtered after 6 months of feeding with experimental diets to investigate meat quality characteristics and fatty acid compositions of muscle.

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The eukaryotic primase/polymerase complex synthesizes approximately 10 primers, one per Okazaki fragment, during the replication of mammalian chromosomes, which contain 10 base pairs. Primase catalyzes the synthesis of a short RNA segment to a single-stranded DNA template. Primase is important in DNA replication because no known replicative DNA polymerases can initiate the synthesis of a DNA strand without an initial RNA primer.

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Ubiquitin-conjugating enzymes (E2) form thioester bonds with ubiquitin (Ub), which are subsequently transferred to target proteins for cellular progress. Ube2K/E2-25K (a class II E2 enzyme) contains a C-terminal ubiquitin-associated (UBA) domain that has been suggested to control ubiquitin recognition, dimerization, or poly-ubiquitin chain formation. Ube2K is a special E2 because it synthesizes K48-linked poly-ubiquitin chains without E3 ubiquitin ligase.

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Prompt removal of misfolded membrane proteins and misassembled membrane protein complexes is essential for membrane homeostasis. However, the elimination of these toxic proteins from the hydrophobic membrane environment has high energetic barriers. The transmembrane protein, FtsH, is the only known ATP-dependent protease responsible for this task.

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Marine fish skin peptides (FSP) have been widely studied due to their antioxidant and antimicrobial properties. We aimed to use a natural antioxidant, FSP, to replacing synthetic preservatives in a pork patty model, which is safer for human body. Moreover, nano-liposome technology can be applied for masking the fishy smell and improving the stability of this peptide.

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Anti-bacterial and anti-viral neuraminidase agents inhibit neuraminidase activity catalyzing the hydrolysis of terminal N-acetylneuraminic acid (Neu5Ac) from glycoconjugates and help to prevent the host pathogenesis that lead to fatal infectious diseases including influenza, bacteremia, sepsis, and cholera. Emerging antibiotic and drug resistances to commonly used anti-neuraminidase agents such as oseltamivir (Tamiflu) and zanamivir (Relenza) have highlighted the need to develop new anti-neuraminidase drugs. We obtained a serendipitous complex crystal of the catalytic domain of Clostridium perfringens neuraminidase (CpNanI) with 2-(cyclohexylamino)ethanesulfonic acid (CHES) as a buffer.

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EF-hand domain-containing protein D2/Swiprosin-1 (EFhd2) is an actin-binding protein mainly expressed in the central nervous and the immune systems of mammals. Intracellular events linked to EFhd2, such as membrane protrusion formation, cell adhesion, and BCR signaling, are triggered by the association of EFhd2 and F-actin. We previously reported that Ca enhances the F-actin-bundling ability of EFhd2 through maintaining a rigid parallel EFhd2-homodimer structure.

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EFhd2/Swiprosin-1 is a cytoskeletal Ca-binding protein implicated in Ca-dependent cell spreading and migration in epithelial cells. EFhd2 domain architecture includes an N-terminal disordered region, a PxxP motif, two EF-hands, a ligand mimic helix and a C-terminal coiled-coil domain. We reported previously that EFhd2 displays F-actin bundling activity in the presence of Ca and this activity depends on the coiled-coil domain and direct interaction of the EFhd2 core region.

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The interaction of the rhomboid pseudoprotease Derlin-1 and p97 is crucial for the retrotranslocation of polyubiquitinated substrates in the endoplasmic reticulum-associated degradation pathway. We report a 2.25 Å resolution structure of the p97 N-terminal domain (p97N) in complex with the Derlin-1 SHP motif.

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RHBDL4 is an active rhomboid that specifically recognizes and cleaves atypical, positively charged transmembrane endoplasmic reticulum-associated degradation (ERAD) substrates. Interaction of valosin-containing protein (p97/VCP) and RHBDL4 is crucial to retrotranslocate polyubiquitinated substrates for ERAD pathway. Here, we report the first complex structure of VCP-binding motif (VBM) with p97 N-terminal domain (p97N) at 1.

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Quinolinate phosphoribosyltransferase (QPRT) catalyses the production of nicotinic acid mononucleotide, a precursor of de novo biosynthesis of the ubiquitous coenzyme nicotinamide adenine dinucleotide. QPRT is also essential for maintaining the homeostasis of quinolinic acid in the brain, a possible neurotoxin causing various neurodegenerative diseases. Although QPRT has been extensively analysed, the molecular basis of the reaction catalysed by human QPRT remains unclear.

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Sometimes, hepatitis B virus (HBV)-related cirrhotic patients with normal aminotransferase levels are closely followed-up for the elevation of aminotransferase levels instead of prompt antiviral therapy (AVT). We analyzed the long-term hepatocellular carcinoma (HCC) risk according to the aminotransferase levels in a retrospective cohort of 1,468 treatment-naïve, HBV-related, compensated cirrhosis patients with elevated HBV DNA levels (≥ 2,000 IU/mL). Based on aminotransferase levels, patients were categorized into normal (< 40 U/L, n = 364) and elevated group (≥ 40 U/L, n = 1,104).

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The mitochondrial calcium uniporter (MCU) is responsible for mitochondrial calcium uptake and homeostasis. It is also a target for the regulation of cellular anti-/pro-apoptosis and necrosis by several oncogenes and tumour suppressors. Herein, we report the crystal structure of the MCU N-terminal domain (NTD) at a resolution of 1.

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Unlabelled: Controversy exists about whether antiviral therapy (AVT) should be recommended for compensated cirrhosis patients with chronic hepatitis B virus (HBV) infection and detectable, but low, serum HBV-DNA levels. A retrospective cohort of 385 treatment-naïve, HBV-related compensated cirrhosis patients (mean age: 51.1 ± 9.

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Meju, a naturally fermented soy block used to produce soy paste and soy sauce in Korea, is suggested to exhibit hypolipidemic and antiinflammatory activities; however, its mechanisms of action are elusive. Here, we report that the water-soluble fibers but not the amino acids and peptides from meju exhibited hypolipidemic activity in vivo. Feeding of fermented soybean fibers (FSF) from meju reduced plasma cholesterol, triglyceride, adipocyte size, and hepatic lipid accumulation in C57BL/6 J mice.

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Sodium chloride is an important ingredient added to most of foods which contributes to flavor enhancement and food preservation but excess intake of sodium chloride may also cause various diseases such as heart diseases, osteoporosis and so on. Therefore, this study was carried out to investigate the effect of monosodium glutamate (MSG) as a salty flavor enhancer on the quality and sensorial properties of the NaCl/MSG complex and actual food system. For characterizing the spray-dried NaCl/MSG complex, surface dimension, morphology, rheology, and saltiness intensity were estimated by increasing MSG (0-2.

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The aim of this study is to type fibers from porcine longissimus dorsi (LD) muscles according to their distribution of myosin heavy chain (MHC) isoforms as well as to investigate fiber characteristics. Four pure types, including types I, IIA, IIX, and IIB were labeled and two hybrid fiber types were subdivided into type IIAX and IIXB by immunohistochemistry using four monoclonal antibodies. Porcine LD muscles were found to have 92.

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Objective: Oral malodor can be increased in breath of liver patients. However, no study has been performed for the association between volatile sulfur compounds (VSCs) and viral hepatitis. The aim of the present study was to determine the relationship between viral hepatitis and VSCs.

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We have determined the crystal structure of porcine quinolinate phosphoribosyltransferase (QAPRTase) in complex with nicotinate mononucleotide (NAMN), which is the first crystal structure of a mammalian QAPRTase with its reaction product. The structure was determined from protein obtained from the porcine kidney. Because the full protein sequence of porcine QAPRTase was not available in either protein or nucleotide databases, cDNA was synthesized using reverse transcriptase-polymerase chain reaction to determine the porcine QAPRTase amino acid sequence.

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Quinolinate phosphoribosyltransferase (QAPRTase) is a key enzyme in NAD biosynthesis; it catalyzes the formation of nicotinate mononucleotide (NAMN) from quinolinate and 5-phosphoribosyl-1-pyrophosphate. In order to elucidate the mechanism of NAMN biosynthesis, crystals of Sus scrofa QAPRTase (Ss-QAPRTase) purified from porcine kidney in complex with NAMN were obtained and diffraction data were collected and processed to 2.1 Å resolution.

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Serum Ca(++) levels play important roles in the humoral immunity. The aim of this study was to detect quantitative trait loci and the associated positional candidate genes affecting baseline serum Ca(++) concentrations. A genome-wide association study was conducted in an F(2) intercross population between Landrace and Korean native pigs using the porcine single nucleotide polymorphism (SNP) 60 K beadchip and the PLINK program based on linear regression.

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Quinolinate phosphoribosyltransferase (QPRTase) is a key NAD-biosynthetic enzyme which catalyzes the transfer of quinolinic acid to 5-phosphoribosyl-1-pyrophosphate, yielding nicotinic acid mononucleotide. Homo sapiens QPRTase (Hs-QPRTase) appeared as a hexamer during purification and the protein was crystallized. Diffraction data were collected and processed at 2.

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