• Applied Biological Chemistry
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• v.30 no.1
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• pp.17-23
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• 1987

Soy milk prepared from soy protein concentrate was fermented with each of the following lactic acid bacteria: Lactobacillus acidophilus KFCC 12731, L. acidophilus AKU 1122, L. bulgaricus, L. casei, Leuconostoc mesenteroides and Streptococcus lactis. The effects of methionine supple mented to soy milk on the growth and acid production by each organism. were investigated. L-methionine reduced the acid production by two strains of L. acidophilus while it had no apparent. effects on the other test cultures. The inhibitory effects of L-methionine on L. acidophilus KFCC 12731 was greater than on L. acidophilus AKU 1122. The acid production by L. acidophilus KFCC 12731 was also reduced substantially by DL-methionine supplemented to soy milk while it was not affected by D-methionine. Supplementation of L-cysteine to soy milk resulted in slight reduction of acid production by L. acido philus KFCC 12731.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.12-16
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• 2007

The function of a protein is closely co-related with its subcellular location(s). Given a protein sequence, therefore, how to determine its subcellular location is a vitally important problem. We have developed a new prediction method for protein subcellular location(s), which is based on n-gram feature extraction and k-nearest neighbor (kNN) classification algorithm. It classifies a protein sequence to one or more subcellular compartments based on the locations of top k sequences which show the highest similarity weights against the input sequence. The similarity weight is a kind of similarity measure which is determined by comparing n-gram features between two sequences. Currently our method extract penta-grams as features of protein sequences, computes scores of the potential localization site(s) using kNN algorithm, and finally presents the locations and their associated scores. We constructed a large-scale data set of protein sequences with known subcellular locations from the SWISS-PROT database. This data set contains 51,885 entries with one or more known subcellular locations. Our method show very high prediction precision of about 93% for this data set, and compared with other method, it also showed comparable prediction improvement for a test collection used in a previous work.

• Molecular & Cellular Toxicology
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• v.1 no.2
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• pp.99-105
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• 2005

Perchloroethylene (tetrachloroethylene, PCE), a dry cleaning and degreasing solvent, can enter ground-water through accidental leak or spills. PCE can be degraded to trichloroethylene (TCE), 1, 1-dichloroethylene (DCE) and vinyl chloride (VC) as potential bio-product. These compounds have been reported that they can cause clinical diseases and cytotoxicity. However, only a little genotoxic information of these compounds has been known. In this study, we investigated DNA single strand breaks of PCE, TCE, DCE and VC by single cell gel electrophoresis assay, (comet assay) which is a sensitive, reliable and rapid method for DNA single strand breaks with mouse lymphoma L5178Y cells. From these results, $37.5\;{\mu}g/ml$ of PCE, $189\;{\mu}g/ml$ of TCE and $56.4\;{\mu}g/ml$ of DCE were revealed significant DNA damages in the absence of S-9 metabolic activation system meaning direct-acting mutagen. And in the presence of S-9 metabolic activation system, $41.5\;{\mu}g/ml$ of PCE, $328.7\;{\mu}g/ml$ of TCE and $949\;{\mu}g/ml$ of DCE were induced significant DNA damage. In the case of VC, it was revealed a significant DNA damage in the presence of S-9 metabolic activation system. Therefore, we suggest that chloroethylene compounds (PCE, TCE, DCE and VC) may be induced the DNA damage in a mammalian cell.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.370-374
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• 1995

By exposing the complex enzyme solution to alkaline condition, it was possible to remove the protease activity selectively without inactivation of soybean cell wall degrading activity of the crude enzyme complex produced by Aspergillus niger CF-34. Optimum reaction conditions were as follow. pH was $9.0{\pm}0.1$, temperature was $20^{\circ}C$ and reaction time was 30 min with gentle stirring. Over 90% of protease activity could be eliminated while the activities of pectinase, polygalacturonase, xylanase, carboxymethyl cellulase and soybean cell wall degrading enzyme were maintained to $80{\sim}100%$. Through alkali treatment, it was discovered that the quality and organoleptic properties of soy protein produced by this enzymes were improved because the hydrolysis of protein and formation of bitter peptide were decreased.

• Korean Journal of Medicinal Crop Science
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• v.3 no.1
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• pp.61-65
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• 1995

Karyotype analysis was carried out in four lines of Bupleurum falcatum L. cultivated in Korea and SDS-PAGE was applied to determine the seed protein profiles among the lines. Chromosomes were classified into two groups, large and small ones. Two kinds of karyotype, 2n=20 and 2n=26, were identified. Chromosome 1 of 2n=20 were all submedian, while that of 2n=26 were median. Chromosomes 2, 3 and 5 of 2n=20 showed polymorphism in size and arm-ratio. Chromosome 2 was submedian, while others were median in the line of 2n=26. Karyotypcs of cultivars native of Korea were similiar each other, while those introduced from Japan showed different patterns. In SDS PAGE gels, qualitative difference s in high molecular weight proteins, more than 45KD, were detected among the lines. The numbers of specific band were three in lines of 2n=20 and two in 2n=26.

• Journal of Life Science
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• v.19 no.7
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• pp.859-865
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• 2009

Microtubules, a major cytoskeleton, form parallel arrays in the axon and are oriented with their plus ends toward the cell periphery. Kinesin superfamily proteins (KIFs) are the molecular motors acting in the microtubule-based motilities of organelles in cells. Here, we used the yeast two-hybrid system to identify the protein that interacts with the coiled-coil domain of KIF1A and found a specific interaction with microtubule-destabilizing factor SCG10. SCG10 bound to the amino acid residues between 400 and 820 of KIF1A, but not to other KIFs in the yeast two-hybrid assay. The coiled-coil domain of SCG10 is essential for interaction with KIF1A. In addition, this specific interaction was also observed in the Glutathione S-transferase pull-down assay. An antibody to SCG10 specifically co-immunoprecipitated KIF1A associated with SCG10 from mouse brain extracts. These results suggest that KIF1A motor protein transports SCG10-containing vesicles along microtubules in neurons.

• Korean Journal of Microbiology
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• v.47 no.4
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• pp.302-307
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• 2011

Native chitin deacetylase of Aspergillus nidulans was purified to apparent homogeneity by a combination of phenyl-Sepharose and Q-Sepharose column chromatography. In order to analyze the amino acid residues involved in the enzyme activity, the enzyme was chemically modified with chemical agent, which selectively reacted with the specific amino acid residue on the protein. When the enzyme was chemically modified with diethylpyrocarbonate, which specifically reacted with histidine residues on the protein, the activity was eliminated. The chitin deacetylase, chemically modified with 100 ${\mu}M$ modifier at the residue of arginine or tyrosine, has shown to have decreased activities. It was shown that the modification at aspartic acid or glutamic acid did not affect the enzyme activity to a greater extent, which would not implicate that acid amino residues were directly involved in catalytic reaction and would affect on the global structures of the proteins. This results demonstrated that histidine and tyrosine residues of enzyme would participate in an important function of the chitin deacetylase activity.

• Journal of the Korean Society of Radiology
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• v.83 no.3
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• pp.486-507
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• 2022

Cerebral small vessel disease (CSVD) includes vascular lesions detected on brain MRI, such as white matter hyperintensities, lacunar infarctions, microbleeds, or enlarged perivascular spaces. There is accumulating evidence that vascular changes may play an important role in development of Alzheimer's disease (AD), and CSVD lesions detected on brain MRI were reported to be associated with β-amyloid and tau proteins accumulation. As the vascular contribution has therapeutic potential, it is important to understand the association of CSVD with AD and AD biomarkers. This review begins with a brief introduction of AD and AD biomarkers, explains the association between AD and vascular changes, and then details the pathogenesis and MR imaging findings of CSVD. Afterwards, we discuss the association of CSVD with AD and AD biomarkers.

• Clinical and Experimental Pediatrics
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• v.48 no.1
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• pp.48-54
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• 2005

Purpose : The pathologic mechanisms of central nervous system(CNS) injuries in human meningitis are not yet completely understood. Recent studies indicate that the host inflammatory responses are as important in brain damage as the infecting organisms and toxins. There have been some reports on the relationship of nitric oxide(NO), macrophage inflammatory protein-$1{\alpha}$(MIP-$1{\alpha}$), and lactoferrin in bacterial meningitis, but few reports in aseptic meningitis. Thus, we investigated the concentrations of NO, MIP-$1{\alpha}$ and lactoferrin in cerebrospinal fluid(CSF) and serum of patients with aseptic meningitis and control subjects and evaluated their relationship with other parameters of meningitis. Methods : CSF and blood were obtained from 25 subjects with aseptic meningitis and 15 control subjects. After centrifugation, supernatants were stored at $-70^{\circ}C$ and we assayed the concentrations of NO, MIP-$1{\alpha}$ and lactoferrin with the ELISA method. There were no patients with neurologic sequelae after being recovered from aseptic meningitis. Results : Concentrations of CSF and serum NO, MIP-$1{\alpha}$ were not increased in aseptic meningitis subjects compared to control subjects. Concentration of CSF lactoferrin was significantly elevated in patients with aseptic meningitis and concentration of serum lactoferrin was significantly decreased in patients with aseptic meningitis compared with those in control subjects(P<0.05). CSF lactoferrin level was positively correlated with CSF WBC counts($r_s=0.449$, P=0.007), especially with neutrophil counts($r_s=0.574$, P<0.001) and CSF protein level($r_s=0.508$, P=0.002). Conclusion : Lactoferrin plays an important role in aseptic meningitis and may be released from neutrophils recruited from blood to the CSF through breakdown of blood-brain barrier. NO and MIP-$1{\alpha}$ may not be important factors in the pathogenesis of aseptic meningitis without neurologic sequelae.

• Childhood Kidney Diseases
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• v.16 no.2
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• pp.102-108
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• 2012

Purpose: We investigated the clinical presentation of febrile pediatric patients with acute pyelonephritis (APN) with a mixed urine culture from an aseptic urine sample, and compared with that of those with a single culture. Methods: We retrospectively reviewed the medical charts of 95 patients diagnosed as APN with fever between January 2008 and October 2010 at Korea University Medical Center. We classified the patients with APN into two groups with a positive single culture (S group) and a positive mixed culture (M group) from an aseptic urine sample of suprapubic bladder aspiration or urethral catheterization and compared the fever duration, laboratory markers such as serum white blood cell (WBC) counts and C-reactive protein (CRP) values in peripheral blood, and the presence of hydronephrosis, renal scar and vesicoureteral reflux (VUR) between the two groups (If presence of hydronephrosis, scar and VUR=1 and no=0). Results: Total pediatric patients with febrile APN were 95 patients, a positive S group was 89 patients and a positive M group was 6 patients. Fever duration (S vs. M, $4.7{\pm}3.1$ vs. $6{\pm}5.7$ days), serum WBC (S vs. M, $18,630{\pm}6,483$ vs. $20,153{\pm}7,660/{\mu}L$) and CRP (S vs. M, $100.6{\pm}2.46$ vs. $81.1{\pm}0.09\;mg/L$) values, and the presence of hydronephrosis, renal scar and VUR were not different between the two groups. Conclusion: Our data shows that there were no specific differences of clinical manifestation between a positive single urine culture and a positive mixed urine culture in pediatric APN. A mixed urine culture from an aseptic urine sample should be interpreted cautiously.