• Title/Summary/Keyword: total amino acids

Search Result 1,875, Processing Time 0.029 seconds

Hydrophobicity of Amino Acids in Protein Context

  • Cho, Hanul;Chong, Song-Ho;Ham, Sihyun
    • Proceeding of EDISON Challenge
    • /
    • 2014.03a
    • /
    • pp.103-113
    • /
    • 2014
  • Hydrophobicity is the key concept to understand the role of water in protein folding, protein self-assembly, and protein-ligand interaction. Conventionally, hydrophobicity of amino acids in a protein has been argued based on hydrophobicity scales determined for individual free amino acids, assuming that those scales are unaltered when amino acids are embedded in a protein. Here, we investigate how the hydrophobicity of constituent amino acids depends on the protein context, in particular, on the total charge and secondary structures of a protein. To this end, we compute and analyze the hydration free energy - free energy change upon hydration quantifying the hydrophobicity - of three short proteins based on the integral-equation theory of liquids. We find that the hydration free energy of charged amino acids is significantly affected by the protein total charge and exhibits contrasting behavior depending on the protein net charge being positive or negative. We also observe that amino acids in the central ${\beta}$-strand sandwiched by ${\beta}$-sheets display more enhanced hydrophobicity than free amino acids, whereas those in the ${\alpha}$-helix do not clearly show such a tendency. Our results provide novel insights into the hydrophobicity of amino acids, and will be valuable for rationalizing and predicting the strength of water-mediated interaction involved in the biological activity of proteins.

  • PDF

The Variation of the Contents of Free Amino Acids and the Carbohydrates in the Whole Plant of Fagopyrum escullentum Moench during the Stages of Growing (모밀(Fagopyrum esculentum Moench)생장과정중의 유리 Amino 산과 당질의 성장에 관하여)

  • 황희자
    • YAKHAK HOEJI
    • /
    • v.8 no.2
    • /
    • pp.48-53
    • /
    • 1964
  • At the different growing stages of Fagopyrum esculentum Moench planted at the green house and out doors, the contents of free amino acids in the whole plants,were determined quantitatively by spot-extract colorimetric method (J. Awapara method) using the chromatograms obtained by the ion-exchange resin and paper chromatographic method. And the contents of carbohydrate in the whole plant were determined by Bertrand method. The results were summarized as follows. 1. Almost same kinds of free amino acids were detected in the both plants. 2. Concentrations of most amino acids was increased progressively during growth; further growth was accompanied by decreased concentrations. 3. Rate of growth and increasing of total amino acid content of green house plant is greater than that of out dorrs plant. 4. At the same stages of gwoth, total free amino acid content of green house plant is higher than that of out doors plant but sugar content is lower. 5. There was rapidly increasing of sugar content and decreasing of total free amino acid content except asparagine during mature of seeds.

  • PDF

The Taste Conpounds of the Fermented Cod-roe, Gadus Macrocephlus - Changes of Free Amino Acids during the Fermentation of Cod-roe - (대구알젓의 맛성분 제I보 : 대구알젓의 유리아미노산)

  • 박재옥
    • Journal of the Korean Home Economics Association
    • /
    • v.20 no.4
    • /
    • pp.99-105
    • /
    • 1982
  • Changes of free amino acids as taste compunds during the fermentation of cod-roe, Gadus marcrocephlus, were analyzed by a amino acid autoanalyzer. Leucine, lysine, valine, isoleucine and arginine were dominent amino acids in fresh cod-roe extracts, and the amounts of leucine (797.3mg%, on moisture and salt free base), lysine (577.7mg%) and valine(487.4mg%0 were 54.9% of total free amino acids. The contents of methionine, histidine, tyrosine and phenylanine were lower, and aspartic acid, glycine, threonine, glutamic acid and serine were detected trace amount. The free amino acids analyzed in this experiment were not changed in composition but changed in the amounts during 80 days of the fermentation. Total free amino acids were increased until 59 days of fermentation and than decreased gradually.

  • PDF

Free amino acids of brown rice in relation to specific gravity grade (비중선별(比重選別) 현미중(玄米中) 유리 Amino산 함량)

  • Park, H.;Chun, J.K.;Cho, I.H.
    • Applied Biological Chemistry
    • /
    • v.15 no.1
    • /
    • pp.35-40
    • /
    • 1972
  • The contents of free amino acids in deembryod brown rice of two varieties were investigated by amino acid autoanalizer in relation to specific gravity grade. The analytical methods of free amino acid were also discussed. 1) The lower the specific gravity of the unhulled rice the higher the content of total free amino acids in the deembryod brown rice, and the similar trend appears to hold on each amino acids. 2) Main free amino acids were serine+asparagine, glutamic acid, aspartic acid, alanine and valine, and maximum values of them were 7.3, 5.1, 4.0, 3.4, 0.9mg/100g rice, respectively. They consist about 85% of total free amino acids in most cases. 3) The contents of soluble nitrogen and free amino acids appear to be lower in high protein variety (IR 667) than in low protein variety (Jinhung). The percentage of free amino acid nitrogen to soluble nitrogen, however, appears to be higher in high protein variety (IR 667). 4) Alanine was much lower than aspartic acid in IR 667 having Indica blood while alanine appears to be higher than aspartic acid in Jinhung (Japonica rice) suggesting varietal difference in amino acid metabolism. 5) Threonine peak was overlaped with glutamine, and serine was with asparagine in this study.

  • PDF

Amino Acid Profiles of Tropical Legumes, Cooper (Glycine wightii), Tinaroo (Neonotonia wightii) and Siratro (Macroptilium atropurpureum), at Pre-blooming and Blooming Stages

  • Tokita, Norio;Shimojo, Masataka;Masuda, Yasuhisa
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.19 no.5
    • /
    • pp.651-654
    • /
    • 2006
  • An experiment was conducted to investigate amino acid composition of three tropical legumes (Cooper (Glycine wightii), Tinaroo (Neonotonia wightii) and Siratro (Macroptilium atropurpureum)) at two different stages (pre-blooming and blooming stages). Chemical composition and totally 16 amino acids of these plants were analysed for comparison of their composition among species at different growing stages and characterizing the amino acid pattern of these legumes. Crude protein content of the plants ranged from 16% to 27% on a dry matter basis. The total amount of 16 amino acids analyzed in this experiment was highest at 89.7 mg/16 g N in Cooper at pre-blooming and lowest at 80.9 mg/16 g N in Glycine at blooming stage. Total amount of amino acids in each legume species tended to slightly decrease with their maturity but no statistical difference was found. The percentage of aspartic acid, glutamic acid and proline in the total amount of amino acids was dominant at 9% to 13%, and that of methionine was less than 1.6%. In this experiment it was concluded that three tropical legumes were rich in crude protein content and characterized by 16 different amino acids with lower sulfur-containing amino acid as methionine.

Compositions of Extractive Nitrogenous Constituents and Their Monthly Variation for Fresh Capsosiphon fulvescens

  • Jung, Kyoo-Jin;Park, Jung-Nim
    • Preventive Nutrition and Food Science
    • /
    • v.15 no.2
    • /
    • pp.120-129
    • /
    • 2010
  • To elucidate the composition of extractive nitrogenous components in the fresh Capsosiphons fulvescens cultured off the southern coast of Korea, and to determine the monthly variation of these nitrogenous components, extract samples collected monthly from December to March at Jangheung-gun, Jeonnam Province were analyzed for total nitrogen, free and combined amino acids, ATP and related compounds, betaines, trimethylamine oxide (TMAO) and trimethylamine (TMA). The content of extractive nitrogen was 1,090~1,233 mg/100 g on dry basis. The number of 21~25 ninhydrin-positive substances was detected in the analysis of free amino acids, and their total amount was 3,710~4,788 mg/100 g on dry basis. Among them, free proline, asparagine, glutamic acid, alanine, taurine and glutamine were found to be abundant. The combined amino acids amounted to 1,573~2,121 mg/100 g in total and the total amount of ATP and related compound was 33.8~84.0 mg/100 g ($1.06{\sim}2.46\;{\mu}mol/g$) on dry basis. Betaine, glycinebetaine, $\beta$-alaninebetaine, $\gamma$-butyrobetaine, homarine and trigonelline were detected in most of samples. Levels of free and combined amino acids, ATP and related compounds fluctuated from sample to sample, with their contents higher in December and January and lower in March.

Chemical composition of different parts of ramie (Boehmeria nivea)

  • Cho, Sunghun;Lee, Jaemin;Kim, Young Mi;Jung, Yong-Su;Kim, Ho Bang;Cho, Eun Ju;Lee, Sanghyun
    • Korean Journal of Agricultural Science
    • /
    • v.44 no.1
    • /
    • pp.95-103
    • /
    • 2017
  • Ramie (Boehmeria nivea) is a perennial herbaceous plant belonging to the family Urticaceae. It was used in folk remedies for diuretic or anti-pyretic purposes and as an hepatoprotective, anti-oxidant, and anti-inflammation agent. In this study, we investigated the composition of free sugars, amino acids, fatty acids, organic acids, and total polyphenol contents in parts of ramie (root, stem, and leaf) and different harvest areas (10 areas). Overall, free sugars were found as sucrose, glucose, fructose, and galactose at concentrations ranging from 24.5 to 1173.8 mg/g. Amino acids lysine, threonine, tyrosine, phenylalanine, and histidine were detected at concentrations of 33.8 to 3735.3 mg/g. Major fatty acids were linoleic acid, palmitic acid, and linolenic acid at concentrations of 7.3 to 364.4 mg/g. In organic acids, the concentration of malic acid was highest of all with 672.2 mg/g. The content of free sugars, amino acids, fatty acids, organic acids, and total polyphenol was higher in leaves than in roots and stems. In contrast, the total polyphenol content was higher in roots with 33.7 - 219.4 mg/g than in leaves or in stems. As seen in collecting region, the contents of free sugars, amino acids, fatty acids, organic acids, and total polyphenol of Bn-33, 39, 55, 65, and 90 were higher than other samples. Chemical compositions of different parts of ramie are important factors to consider in manufacturing functional foods. The results of this study provide fundamental information on the chemical compositions of ramie parts and would help develop new functional foods from ramie leaves or the whole plant.

Effects of $\gamma$-Irradiation and Subsequent Storage on Amino Acids and Ribonucleotides of Biled-Dried Anchovy

  • Kwon, Joonh-Ho;Byun, Myung-Woo
    • Preventive Nutrition and Food Science
    • /
    • v.1 no.1
    • /
    • pp.16-22
    • /
    • 1996
  • Amino acids and ribonucleotides were measured for boiled-dried anchovy to determine the effect of 5 kGy γ-irradiation on its quality stability during storage at ambient and cooling (5∼10℃) temperatures for 12 months in a laminated-film package(Polyethylene 10㎛). The anchovy samples contained about 55%(d.b) of total amino acids and about 1%(d.b) of free amino acids. Although there found a significant change(p<0.01) in the content of leucine and lysine immediately sfter irradiation, the overall content of toral amino acids was little changed in stored anchovy even six months after irradiation at cooling conditions. γ-Irradiation caused a significant reduction(p<0.01) in the total content of free amino acids, showing a similar tendency by storage conditions. However, the ribonucleotides. which were 12.00mg/g(d.b) in inosine-5'-monophosphate and 0.38mg/g(d.b) in guanosine-5'-monophospate, were resistant to 5kGy-irradiation. With the lapse of storage time, it was also shown that storage temperature was more influential than irradiation on the contents of amino acids and taste compounds of dried anchovy.

  • PDF

Monitoring of Dynamic Changes in Maillard Reaction Substrates by Response Surface Methodology (반응표면분석에 의한 Maillard 반응기질의 동적변화 모니터링)

  • Lee, Gee-Dong;Kim, Jeong-Sook;Kwon, Joong-Ho
    • Korean Journal of Food Science and Technology
    • /
    • v.28 no.2
    • /
    • pp.212-219
    • /
    • 1996
  • Four-dimensional response surface methodology was used for monitoring dynamic changes in substrates during Maillard reaction. The coefficients of determination ($R^2$) of response surface regression equations for the changes in amino acids during Maillard reaction were 0.9478 for total amino acids and above 0.90 for each amino acid. $R^2$ of regression equations for the changes in sugars during Maillard reaction were 0.9250 for glucose and 0.6490 for fructose. The contents of total amino acids gradually decreased with increasing reaction temperature and pH of the solvent. Browning color intensity increased with rising reaction temperature, showing maximum color intensity at around $145^{\circ}C$. Each amino acid showed a decreasing tendency in its contents, which was similarly found in total amino acids. Four-dimensional response surface methodology indicated that the increased temperature during Maillard reaction was the most influential factor in decreasing substrates, such as aspartic acid, threonine and glucose. While the reaction time and pH of solvent little affected the changes in the above-mentioned substrates during Maillard reaction.

  • PDF

Changes in the Compositions of Amino Acids in the Rice Seedlings under Low Temperature (저온처리한 벼 유식물의 아미노산 조성의 변화)

  • 문병용
    • Journal of Plant Biology
    • /
    • v.32 no.4
    • /
    • pp.235-245
    • /
    • 1989
  • The contents and the compositions of total free amino acids were investigated in the rice(Oryza sativa L. cv. Chuncheong) seedlings under low temperatures. Activities of some enzymes associated with the markedly changed amino acid content were also investigaetd. Under low temperature, the contents of soluble protein and the total free amino acids increased, while the content of total nitrogen decreased. Although asparagine+glycine were the most abundant amino acid speceis in the rice seedlings at the control temeprature, low temperature treatment for 3days brought about the decrease in their amount to about 60% level of the control plants. On the other hand, alanine showed the highest increase in the content among all the free amino acids, though glutamine, proline, asprtic acid, valine and tyrosine also increased after low temperature treatment. To eludicate the decrease of asparagine+glycine level under low temperature, the activities of asparagine aminotransferase and asparaginase which metabolize asparagine were investigated in the rice seedlings under low temperature. The activity of asparaginase increased markedly, while that of asparagine aminotransferase decreased under low temperatures. Therefore, it was suggested that asparaginase metabolizes asparagine predominatly in the rice seedlings under low temperatures.

  • PDF