• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.680-686
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• 2010

Inhibition effects of alanine(Ala), asparagine(Asn), aspartic acid(Asp), glutamine(Gln) and methionine(Met) on the corrosion of copper were investigated in aerated artificial sea water. Amino acid adsorption process in copper surface can be explained by Temkin logarithmic isotherm due to the interaction between the adsorbed molecules. The inhibition efficiency for the copper corrosion depended on the concentration of amino acids.

• Journal of Integrative Natural Science
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• v.9 no.4
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• pp.228-233
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• 2016

Cysteinyl leukotrienes are inflammatory mediators having important role in pathophysiological conditions such as asthma and allergic rhinitis. CysLT1 receptor mediates most of the disease regulatory actions of the CysLTs and it is been implicated in a number of inflammatory conditions including gastrointestinal and cardiovascular diseases. Hence in the present study, molecular docking of CysLT1 was performed with its potent and orally efficacious antagonist CP-199330 and CP-199331. The aim of this study was to compare the interaction of CP-199330 and CP-199331 with known drugs such as Zafirlukast, Pranlukast and Montelukast which had already showed clinical efficacy in the treatment of asthma. The residues such as TYR83, GLN274, LYS311 and SER313 were found to interact with both the antagonist and the known drugs. Also, we noticed the docking scores and interaction of the antagonists were comparable with the known drugs. Hence these antagonists could serve as better drugs for the treatment of allergy.

• Biomedical Science Letters
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• v.8 no.4
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• pp.245-250
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• 2002

Fibrinolytic enzyme has been purified from the edible mushroom, Tricholoma sejunctum using DEAE-cellulose chromatography, Phenyl-Sepharose chromatography and Mono-S column chromatography. The apparent molecular mass of purified enzyme was estimated to be 17100 Da by SDS-polyacrylamide gel electrophoresis and 19000 Da by gel filtration, Indicating that it was a monomer. The N-terminal amino acid sequence of the enzyme was Ala-Thr-Tyr-Lys-Ile-X-Ser-Ala-Thr-His-Gln-X-X-Leu-Val. It has a pH optimum at pH 9.5, suggested that purified enzyme was a alkaline protease. The activity of purified enzyme was inhibited by EDTA and 1,10-phenanthroline, indicating that purified enzyme is a metalloprotease. The activity of purified enzyme was increased by Zn$^{2+}$ and Co$^{2+}$, however, the enzyme activity was totally inhibited by Hg$^{2+}$.

• Korean Journal of Environmental Agriculture
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• v.16 no.1
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• pp.55-60
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• 1997

Heavy metal-tolerant microorganisms, such as Pseudomonas putida, P. aeruginosa, P. chlororaphis and P. stutzeri which possessed the ability to accumulate cadmium, lead, zinc and copper, respectively, were isolated from industrial wastewaters and mine wastewaters polluted with various heavy metals. The distribution of heavy metal in the cell components, and amino acid compositions, was investigated. The distribution of heavy metal in the cell fractions of each heavy metal-tolerant microorganism grown for 20 hours in the basal medium containing 100mg/l of each heavy metal was investigated. In the case of cadmium-tolerant P. putida, lead-tolerant P. aeruginosa and copper-tolerant P. stutzeri, approximately $50{\sim}60%,\;30{\sim}40%$ and $10{\sim}17%$ of each heavy metal absorbed were distributed to cell wall, cell membrane and cytoplasm fractions, respectively. In the case of zinc-tolerant P. chlororaphis, approximately 32%, 55% and 13% of zinc were distributed to cell wall, cell membrane and cytoplasm fractions, respectively. These results indicated that the cell wall was a major adsorbing fraction of cadmium, lead and copper, and the cell membrane was that of zinc. Total amino acid content per gram of the cell grown in the culture media with heavy metal was higher than that of the cell grown in the culture media without heavy metal, and the content of acidic amino acids, such as aspartic acid(Asp.+Asn.) and glutamic acid(Glu.+Gln.) was higher than that of basic amino acids, such as histidine, lysine and arginine.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.2
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• pp.164-172
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• 2001

The angiotensin-I converting enzyme (ACE) inhibitors from laver hydrolysate was isolated. Among the 13 kinds of proteases, Maxazyme NNP was most effective for preparing the high ACE inhibitory compound. In extraction conditions of ACE inhibitory peptide from laver hydrolysate, ACE inhibitory activity of hydrolysate treated with diethylether for decolorization and that of $70\%$ ethanol soluble fraction among the different ethanol concentrations were higher than other preparations. Low molecular fraction less than 3,000 dalton of layer hydrolysate separated by ultrafiltration had the highest ACE inhibitory activity, for further separation of ACE inhibitory peptide from laver hydrolysate, gel filtration chromatography (Sephadex G-25), reverse-phase HPLC (ODS & Vydac C-18) and gel permeation chromatography (Superdex Peptide HR) were performed. The molecular mass of the ACE inhibitory peptide fractions of gel permeation chromatography determined by electrospray-mass spectrometer were 413.48 (S1O2V2V1P),346.86 (S1O2V2V2P) and 320.32 (S2O6V3V1P) dalton and their amino acid sequence were Val-Gln-Gly-Asn, Thr-Glu-Thr and Phe-Arg, respectively.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.6 no.2
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• pp.112-119
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• 2003

Purpose: Helicobacter pylori infection is thought to be correlated with iron-deficiency anemia (IDA) at puberty. The H. pylori feoB gene, a high-affinity ferrous iron transporter, plays a central role in iron acquisition. This study aims to analyze the H. pylori feoB status according to the presence of antral gastritis with or without IDA. Methods: Fourteen H. pylori-positive patients aged from 10~18 years were categorized into subgroups based on the presence or absence of IDA. Eight patients had IDA, and the other six showed normal hematological findings. Genomic DNA was isolated from cultured H. pylori. Five sets of primers were used for PCR amplification of the feoB gene. The feoB region, 1.93 kb, was generated by linking of the PCR products and sequenced. The feoB gene sequences of H. pylori J99 and 26695 were used to compare with the clinical strains. Sequence comparisons of the feoB regions between the IDA (+) and (-) groups were performed. Results: Sequence analysis of the complete coding region of the feoB revealed 16 sites of polymorphism. Among these, 3 polymorphisms-Glu/Thr254Ala, Ile263Val, and Lys511Gln - were indigenous to Korean strains. Although statistically significant differences appear in 4 sites between IDA (+) and (-), the number of specimens are too low to assess the real differences. Conclusion: The 4 polymorphisms in the feoB gene seem to be related with IDA, but it is unclear yet because of small number of study strains. Further studies are required to prove the correlation of IDA and H. pylori infection.

• Journal of Korean Medicine for Obesity Research
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• v.3 no.1
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• pp.7-16
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• 2003

Objectives : The lipolytic effects of catecholamines in adipose tissue are mediated by members of adrenergic receptors. This study was conducted to examine the effects of ${\beta}2-AR$ Gln27Glu (Q27E) polymorphism on obesity indices and risk among obesity clinic patients. Methods : 532 subjects, 38 men and 494 women, who attended a weight loss program in a local obesity clinic were analyzed. Height, weight, BMI, WHR and obesity index were measured or calculated. Body composition was measured by bio-impedance analysis. Genotype of ${\beta}2-AR$ polymorphism in codon 27 was analyzed by PCR-RFLP method. Serum concentrations of fasting glucose, total and HDL cholesterol, and triglyceride were determined by autobiochemical analyzer. Results: The Genotype distributions of ${\beta}2-AR$ gene were QQ type 81.3%, QE type 17.9% and EE type 8%. Therefore, the frequency of E allele of ${\beta}2-AR$ gene was 0.170 in the total subjects. The frequency of the ${\beta}2-AR$ variant genotype(QE+EE) was significantly higher in obese group($BMI{\geqq}25$) compared with non-obese group(p=0.027). Weight was significantly higher in variant(QE+EE) type compared with normal(QQ) type in total subjects(p=0.001), male(p=0.022) and female(p=0.013). BMI, obesity index and WHR were also significantly higher in QE+EE type. Body fat man was significantly higher in QE+EE type in total subjects(p=0.005) and female(p=0.027). When forward stepwise regression analysis was used to create a model of risk predictors of obesity($BMI{\geqq}25$), QE+EE type of ${\beta}2-AR$ gene was found to be a significant risk factor for obesity (p=0.042, ORs 1.597). Conclusions: QE+EE genotype of ${\beta}2-AR$ was associated with increased obesity indices and might be a significant risk factor for obesity.

• Journal of Life Science
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• v.16 no.3 s.76
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• pp.485-492
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• 2006

The PrrBA two-component system is one of the major regulatory systems that control expression of photosynthesis genes in response to changes in oxygen tension in the anoxygenic photosynthetic bacterium, Rhodobacter sphaeroides. The system consists of the PrrB histidine kinase and the PrrA response regulator. The N-terminal transmembrane domain of PrrB serves as a signal-sensing domain and comprises six transmembrane helices forming three periplasmic loops and two cytoplasmic loops. The $3^{rd}$ and $4^{th}$ transmembrane helices and the $2^{nd}$ periplasmic loop were suggested to play a crucial role in redox-sensory function. In this study we demonstrated that mutations of Asp-90, Gln-93, Leu-94, Leu-98, and Asn-106 in the $2^{nd}$ periplasmic loop and its neighboring region led to severe defects in PrrB sensory function, indicating that these amino acids might be related to the redox-sensing function of PrrB. The mutant forms (D90E, D90N, and D90A) of PrrB were heterologously overexpressed in Escherichia coli, purified by means of affinity chromatography and their autokinase activities were comparatively assessed. The D90N form of PrrB was shown to possess higher autokinase activity than the wild-type form of PrrB, whereas the D90E form of PrrB displayed lower autokinase activity than the wild-type form of PrrB. The D90A mutation led to the loss of PrrB autokinase activity.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.215-221
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• 2009

Site-specific incorporation of unnatural amino acids into proteins in vivo can be achieved by co-expression of an orthogonal pair of suppressor tRNA and engineered aminoacyl-tRNA synthetase (ARS) that specifically ligates an unnatural amino acid to the suppressor tRNA. As a step to establish this technique, here we generated an Escherichia coli reporter strain DH10B(Tn:lacZam) by integrating amber mutated lacZ gene into the chromosome of E. coli DH10B strain. In vivo expression of E. coli amber suppressor $tRNA^{Gln}$ produced blue colonies in culture plates containing X-Gal as well as dramatically increased $\beta$-galactosidase activity. In addition, expression of an orthogonal pair of Saccharomyces cerevisiae suppressor $tRNA^{Tyr}$ and tyrosyl-tRNA synthetase also produced blue colonies as well as moderate increase of $\beta$-galactosidase activity. These data demonstrate that our reporter strain will provide an efficient method to assess amber suppression in both qualitative and quantitative manners.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.250-252
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• 2014

Lipoprotein-associated phospholipase A2 (Lp-$PLA_2$) is a crucial enzyme in atherosclerosis as a potential drug target. The most remarkable Lp-$PLA_2$ inhibitory drug is Darapladib. We determined the binding pose of Darapladib to Lp-$PLA_2$ through docking study. Darapladib formed two hydrogen bonding interactions with the side chain of Tyr160 and Gln352 and several pi-pi interactions with aromatic and aliphatic hydrophobic residues of Lp-$PLA_2$. It is known that the dietylpropan-amine moiety of Darapladib has influence on the improvement of its oral bioavailability and we supposed this in our docking results.