• Title/Summary/Keyword: Lysine

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Simple Iysine sensing system using $CO_{2}$ electrode and enzyme immobilized to CNBr-activated sepharose 4B

  • Kim, Eun-Jung;Koh, Kwang-Nak;Choi, Myung-Sook
    • Journal of Sensor Science and Technology
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    • v.6 no.6
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    • pp.437-444
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    • 1997
  • A potentiometric L-lysine-selective sensor is described for the direct determination of lysine. The sensor system is based on a carbon dioxide gas sensing electrode and an L-lysine decarboxylase immobilized to CNBr-activated sepharose 4B. A highly selective L-lysine sensor has been prepared with immobilizing enzyme slurry put into reaction buffer solution. The optimum conditions for the measurement were evaluated by various experiments. This sensor exhibits a linear response to L-lysine concentrations from $10^{-4}M$ to $10^{-1}M$. Response time of this lysine sensor is shorter than 30secs and the immobilized enzyme slurry is stable over one year.

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Production and Evaluation of Immunoreactivity of Poly Lysine-Tagged Single Chain Fragment Variable (ScFv) Lym-1 Antibody for Direct Conjugation to Fluorescence Dye (형광 물질 직접 표지를 위한 Poly Lysine 도입 Lym-1 단일사슬 항체의 제조 및 면역반응성 평가)

  • Jung, Jae-Ho;Choi, Tae-Hyun;Woo, Kwang-Sun;Chung, Wee-Sup;Kang, Joo-Hyun;Jeong, Su-Young;Choi, Chang-Woon;Lim, Sang-Moo;Cheon, Gi-Jeong
    • Nuclear Medicine and Molecular Imaging
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    • v.43 no.5
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    • pp.487-494
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    • 2009
  • Purpose: Small size of recombinant scFv antibody has many advantages such as rapid blood clearances and improved targeting antibodies to tumor region. On the other hand owing to small size, number of amino group is insufficient in conjugation with chelator and fluorescence labeling. This study is to introduce poly lysine tag to the C-terminal end of scFv lym-1 sequence for fluorescence chelator conjugation. Materials and Methods: Poly lysine scFv lym-1 gene, cloned into pET-22b (+) vector, was expressed in E. coli BL21 (DE3) strain. Antibody purification was performed with Ni-NTA column and then size exclusion column chromatography. Expression and purification levels of poly lysine tagged scFv lym-1 antibody were confirmed by western blot analysis. I-124, I-125, I-131 and Tc-99m were used for radiolabeling of purified poly lysine scFv lym-1. Flow cytometry analysis of FIT( conjugated poly lysine scFv lym-1 was performed for confirmation of immunoreactivity of human Burkitt's lymphoma cells. Results: Poly lysine scFv lym-1 antibody was purified through two steps and identified as molecular weight of 48 KDa. Radiolabeling yields of I-124, I-125, I-131 and Tc-99m into poly lysine scFv lym-1 were >99%, >99%, >95% and >99%, respectively. Flow cytometry analysis of poly lysine scFv and scFv lym-1 was showed similar immunoreactivity to human Burkitt's lymphoma cells. Conclusion: Poly lysine tag was useful for the sufficient number of amino groups to scFv lym-1 antibody for chelator conjugation with minimizing loss of immunoreactivity.

A Study of Liver Lipid Accumulation, Free Amino Acid in Plasma and Liver on Rats Fed Wheat Flour Diet Supplemented With Lysine and Sesame (소맥분(小?粉)에 참깨와 Lysine을 보족(補足)한 흰쥐의 간지질축적(肝脂質蓄積)과 Plasma 및 간장중(肝臟中)의 유리(遊離) 아미노산(酸)에 대(對)하여)

  • Lee, Myoung-Hi
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.10 no.1
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    • pp.77-84
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    • 1981
  • The effect of sesame of L-lysine HCI and sesame supplementing a wheat flour diet on growth, liver lilpid content, and on the free amino acid levels in the plasma and liver was studied in young male rats with an initial body weight of $75{\pm}3g$. The free amino acids were analyzed by amino acid auto analyzer (JLC - 6HA, NO. 310). The results were as follows. The body weitht gain on L-lysine HCI and sesame supplemented diet was more than weight in the sesame added diet or wheat flour diet groups. Also the liver lipid contents of rats on a wheat flour diet supplemented with L-lysine HCI and sesame showed greater increases than the levels in rats on the wheat flour diets. The rate of liver lipid accumulation was depressed in rats fed L-lysine HCI supplemented wheat flour containing sesame than in rats fed soybean oil or shortening oil instead of sesame. The free phe. Tyr. Leu. Ileu. Val. Lys. levels in the plasma of rats administered the wheat flour diets supplemented with 0.25% L-lysine HCI were higher than those of rats without L-lysine HCI. The free phe. Tyr. Asp. His. Lys. contained in the liver were increased, but other free amino acids were decreased according to the L-lysine HCI amount.

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An Overlooked Effect of Glycine Betaine on Fermentation: Prevents Caramelization and Increases the $\small{L}$-Lysine Production

  • Xu, Jianzhong;Xia, Xiuhua;Zhang, Junlan;Guo, Yanfeng;Zhang, Weiguo
    • Journal of Microbiology and Biotechnology
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    • v.24 no.10
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    • pp.1368-1376
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    • 2014
  • This article focuses on the effects of glycine betaine on preventing caramelization, and increasing DCW and $\small{L}$-lysine production. The additional glycine betaine not only decreased the browning intensity (decreased 4 times), and the concentrations of 5-hydroxymethylfurfural (decreased 7.8 times) and furfural (decreased 12 times), but also increased the availability of glucose (increased 17.5%) for $\small{L}$-lysine production. The DCW and $\small{L}$-lysine production were increased by adding no more than 20 mM glycine betaine, whereas the DCW and $\small{L}$-lysine production were decreased with the reduction of pH values, although pH had a better response to prevent caramelization than did glycine betaine. For $\small{L}$-lysine production, the highest increase (40%) was observed on the media with 20 mM glycine betaine. The crucial enzymes in glycolysis and $\small{L}$-lysine biosynthesis pathway were investigated. The results indicated that additional glycine betaine increases the activity of enzymes in glycolysis, in contrast to the effect of pH. All the results indicated that glycine betaine can be used to prevent caramelization and increase the $\small{L}$-lysine production. By applying this strategy, glucose would not be have to be separated from the culture media during autoclaving so that factories can save production costs and shorten the fermentation period.

Histone Lysine Methylation (히스톤 라이신 메틸화)

  • Kwak, Sahng-June
    • Journal of Life Science
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    • v.17 no.3 s.83
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    • pp.444-453
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    • 2007
  • Our genome exists in the form of chromatin, and its structural organization should be precisely regulated with an appropriate dynamic nature for life. The basic unit of chromatin is a nucleosome, which consists of a histone octamer. These nucleosomal histones are subject to various covalent modifications, one of which is methylation on certain lysine residues. Recent studies in histone biology identified many histone Iysine methyltransferases (HKMTs) responsible for respective lysine residues and uncovered various kinds of involved chromatin associating proteins and many related epigenetic phenotypes. With the aid of highly precise experimental tools, multi-disciplinary approaches have widened our understanding of how lysine methylation functions in diverse epigenetic processes though detailed mechanisms remain elusive. Still being considered as a relatively more stable mark than other modifications, the recent discovery of lysine demethylases will confer more flexibility on epigenetic memory transmitted through histone lysine methylation. In this review, advances that have been recently observed in epigenetic phenotypes related with histone lysine methylation and the enzymes for depositing and removing the methyl mark are provided.

Development of a Method to Quantify Lysine in Small Amount of Rice Grain

  • Kim, Joo-Shin;Kim, Kwang-Jin;Ma, Wing Chi Joyce;Chung, Hau-Yin
    • Journal of environmental and Sanitary engineering
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    • v.22 no.2
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    • pp.75-84
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    • 2007
  • A lysine determination method for low quantity of rice was modified from the original Dye-Binding Lysine (DBL) method used in the national standard in China [GB 4801-84, 1984]. By making use of the property that lysine does not bind to the crocein orange G dye after treated with propionic anhydride, the amount of lysine in rice samples could be determined directly by calculating the difference between the absorbances of the treated and the untreated samples. Various commercial rice samples were purchased from market and evaluated. Several methods were tested by varying both the sizes of the samples and the concentrations of the dye solutions. Results showed that when using 1.284 mM of crocein orange G dye solution and 15.5 mg of sample, the results were most reproducible. The corresponding lysine content in sample were $3.36\;{\pm}\;0.09\;mg/g$ and $3.35\;{\pm}\;0.19\;mg/g$ by traditional method and modified method, respectively. Statistically, there was no significant difference between the results (p>0.05).

Molecular characterization of lysine 6-dehydrogenase from Achromobacter denitrificans

  • Ruldeekulthamrong, Prakarn;Maeda, Sayaka;Kato, Shin-ichiro;Shinji, Nagata;Sittipraneed, Siriporn;Packdibamrung, Kanoktip;Misono, Haruo
    • BMB Reports
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    • v.41 no.11
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    • pp.790-795
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    • 2008
  • An inducible lysine 6-dehydrogenase (Lys 6-DH), which catalyzes the oxidative deamination of the 6-amino group of L-lysine in the presence of $NAD^+$, was purified to homogeneity from Achromobacter denitrificans, yielding a homodimeric protein of 80 kDa. The enzyme was specific for the substrate L-lysine and $NAD^+$ served as a cofactor. The dimeric enzyme associated into a hexamer in the presence of 10 mM L-lysine. The $K_m$ values for L-lysine and $NAD^+$ were 5.0 and 0.09 mM, respectively. The lys 6-dh gene was cloned and overexpressed in E. coli. The open reading frame was 1,107 nucleotides long and encoded a peptide containing 368 amino acids with 39,355 Da. The recombinant enzyme was purified to homogeneity and characterized. Enzyme activities and kinetic properties of the recombinant enzyme were almost the same as those of the endogenous enzyme obtained from A. denitrificans. Crystals of the enzyme were obtained using the hanging drop method.

Nutritional Regulation of GLUT Expression, Glucose Metabolism, and Intramuscular Fat Content in Porcine Muscle

  • Katsumata, M.;Kaji, Y.;Takada, R.;Dauncey, M.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.8
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    • pp.1297-1304
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    • 2007
  • We conducted a series of investigations in order to elucidate role of nutritional status in regulating GLUT expression and energy metabolism in porcine muscle. Firstly, the role of mild undernutrition in regulating muscle GLUT gene expression and function was studied in growing pigs (3 wk of age) on a high (H) or low (L) food intake (H = 2L) at $35^{\circ}C$ or $26^{\circ}C$. Low food intake selectively upregulates GLUT1 and GLUT4 gene expression; mRNA levels were elevated in longissimus dorsi (L. dorsi) and rhomboideus muscles but not in diaphragm or cardiac muscles. Our next step was to determine whether dietary lysine, a major primary limiting amino acid in diets for pigs, affects muscle GLUT4 expression. Pigs of 6 wk of age were pair-fed a control or low lysine (LL) diet. The control diet contained optimal amounts of all essential amino acids, including 1.15% lysine. The LL diet was similar but contained only 0.70% lysine. GLUT4 mRNA expression was upregulated by the LL diet in L. dorsi and rhomboideus muscles, whereas that in cardiac muscle was unaffected. GLUT4 protein abundance was also higher in rhomboideus muscle of animals on the LL diet. We conducted another investigation in order to elucidate effects of the LL diet on post-GLUT4 glucose metabolism. Activity of hexokinase was unaffected by dietary lysine levels while that of citrate synthase was higher both in L. dorsi and rhomboideus muscles of pigs fed on the LL diet. Glucose 6-phosphate content was higher in L. dorsi msucle in the LL group. Glycogen content was higher both in L. dorsi and rhomboideus muscles in the LL group. Further, we determined the effects of dietary lysine levels on accumulation of intramuscular fat (IMF) in L. dorsi muscle of finishing pigs. A low lysine diet (lysine content was 0.40%) meeting approximately 70% of the requirement of lysine was given to finishing pigs for two months. IMF contents in L. dorsi of the pigs given the low lysine diet were twice higher than those of the pigs fed on a control diet (lysine content was 0.65%). Finally, we proved that a well known effect of breadcrumbs feeding to enhance IMF of finishing pigs could be attributed to shortage of amino acids in diets including breadcrumbs.

Effects of Dietary Lysine Levels on Apparent Nutrient Digestibility and Serum Amino Acid Absorption Mode in Growing Pigs

  • Zeng, P.L.;Yan, H.C.;Wang, X.Q.;Zhang, C.M.;Zhu, C.;Shu, G.;Jiang, Q.Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.7
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    • pp.1003-1011
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    • 2013
  • Two experiments were conducted to determine the effects of different dietary lysine levels on the apparent nutrient digestibility, the serum amino acid (AA) concentration, and the biochemical parameters of the precaval and portal vein blood in growing pigs. In Experiment 1, 15 noncannulated pigs received diets with different lysine densities (0.65%, 0.95%, and 1.25% lysine) for 13 d. A total collection digestion test was performed, and blood samples were collected from the precaval vein at the end of the experiment. In Experiment 2, four cannulated pigs were fed the same diets of Experiment 1. The experiment used a self-control experimental design and was divided into three periods. On d 5 of each period, at 0.5 h before feeding and hourly up to 8 h after feeding, single blood samples were collected from catheters placed in the portal vein. In Experiment 1, some serum AAs (including lysine), serum urinary nitrogen (SUN), and total protein (TP) concentrations were significantly affected by the dietary lysine levels (p<0.05). Moreover, the 0.65% lysine treatment showed a significant lower apparent digestibility of gross energy, dry matter, crude protein, and phosphorus than the other treatments (p<0.05). In Experiment 2, serum lysine, histidine, phenylalanine, threonine, valine, isoleucine (p = 0.0588), triglyceride, and SUN (p = 0.0572) concentrations were significantly affected by the dietary lysine levels (p<0.05). Additionally, almost all of the determined serum AA and total AA concentrations reached their lowest values at 0.5 h before feeding and their highest values at 2 h after feeding (p<0.05). These findings indicate that the greatest absorption of AA occurred at 2 h after feeding and that the dynamic profile of serum AA is affected by the dietary lysine levels. Moreover, when the dietary lysine content was 0.95%, the growing pigs achieved a better nutrient digestibility and serum metabolites levels.

Lysine Fortification of Milssal and Some Observation on the Fortified Product (밀쌀의 라이신 강화(强化) 및 강화(强化)밀쌀의 식품영양학적(食品營養學的) 고찰(考察))

  • Cheigh, Hong-Sik;Pyun, Yoo-Ryang;Kwon, Tai-Wan
    • Korean Journal of Food Science and Technology
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    • v.6 no.2
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    • pp.109-115
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    • 1974
  • Milssal is a polished, partially gelatinized pressed wheat grain and it is being consumed in Korea. This study was conducted to establish 2 practical means of providing needed lysine to the Korean population through fortification of Milssal. The results are summarized as follow: Lysine infusion of Milssal was significantly higher than polished wheat grain and affected by such factors as time and concentration of infusion solution. Cooking characteristics including water-uptake ratio and expanded volume were apparently better than polished wheat. After conducting the series of fortification experiments under actual manufacturing conditions. a reasonable process was chosen. In the developed process. lysine HCl solution was sprayed instead of water to the cleaned and debranned wheat grains during the regular wetting process. There was no differences in appearance and taste of Milssal before and after fortification. Fortification of the protein of Milssal with lysine has been found to bring a significant improvement in the growth rate of rats and the protein efficiency ratio. Stability remained relatively high throughout the storage period(90 days at $10{\sim}20^{\circ}C$ or 30 days at $37^{\circ}C$).

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