• Applied Biological Chemistry
• /
• 제5권
• /
• pp.39-42
• /
• 1964

1) 진석화(眞石花)젓은 그 수분함량(水分含量)이 생(生)굴에 비(比)하여 상당(相當)히 감소(減少)하여 농축(濃縮)된 상태(狀態)이며, glycogen의 함량(含量)도 격감(激減) 하였음에 반(反)하여 유리당(遊離糖)은 현저(顯著)하게 증가(增加)되었다. 2) Paper chromatography로 시료(試料) 즙액중(汁液中)에서 검출(檢出) 확인(確認)된 유리(遊離) 아미노산(酸)는 aspartic acid, glutamic acid, cystine, serine, glycine, lysine, threonine histidine, alanine, arginine, valine, methionine, tyrosine, phenylalanine, leucine, iso-leucine, tryptophan 등 17종(種)이 였으며, 영양상(榮養上) 필수(必須) amino acid를 전부(全部) 함유(含有)하고 있었다. 3) 비색정량법(比色定量法)에 의(依)해서 정량(定量)된 시료(試料) 즙액중(汁液中) 유리(遊離) 아미노산(酸)의 함량(含量)은 Tyr. 0.264mg/ml, Arg. 0.304mg/ml, Try. 0.046mg/ml, His. 0.460mg/ml, Met. 0.350mg/ml, Cys. 0.440mg/ml, phe. 0.115mg/ml 이었다.

• BMB Reports
• /
• 제29권4호
• /
• pp.277-285
• /
• 1996

In Pseudomonas fluorescens grown on malonate as sole carbon source, acetyl-CoA synthetase was induced, suggesting that malonate is metabolized through acetate and then acetyl-CoA. Acetyl-CoA synthetase was purified 18.6-fold in 4 steps to apparent homogeneity. The native molecular mass of the enzyme estimated by a native acrylamide gel electrophoresis was 130 kDa. The enzyme was composed of two identical subunits with a molecular mass of 67 kDa. Optimum pH was 70. The acetyl-CoA synthetase showed typical Michaelis-Menten kinetics for the substrates, acetate, ATP and CoA, whose $K_m$ values were calculated to be 33.4, 74.8, and 40.7 mM respectively. Propionate. butyrate and pentanoate were also used as substrates by the enzyme, but the rate of the formation of the CoA derivatives was decreased in the order of the increase in carbon number. The enzyme was inhibited by the group-specific reagents diethylpyro-carbonate, 2,3-butanedione, pyridoxal-5'-phosphate and N-bromosuccinimide. In the presence of substrates the inactivation rate of the enzyme, by all of the group-specific reagents mentioned above decreased, indicating the presence of catalytically essential histidine, arginine, lysine and tryptophan residues at or near the active site. Preincubation of the enzyme with ATP, $Mg^{2+}$ resulted in the increase of its susceptibility to diethylpyrocarbonate, suggesting that ATP, $Mg^{2+}$ may induce a conformational change in the active site exposing the essential histidine residue to diethylpyrocarbonate. The enzyme was acetylated in the presence of acetyl-CoA, indicating that this is one of acyl-enzyme.

• BMB Reports
• /
• 제31권5호
• /
• pp.498-502
• /
• 1998

HBV polymerase shares several regions of amino acid homology with other DNA-directed and RNA-directed polymerases. The amino acid residues $Asp^{429}$, $Gly^{518}$, $Asp^{551}$, $Lys^{585}$, and $Gly^{641}$ in the conserved motifs A, B', C, D, and E in the polymerase domain of HBV polymerase were mutated to alanine or histidine by in vitro site-directed mutagenesis. Those mutants were overexpressed, purified, and analyzed against DNA-dependent DNA polymerase activity and affinity for DNA binding. All those mutants did not show DNA-dependent DNA polymerase activities indicating that those five amino acid residues are all critical in DNA polymerase activity. South-Western analysis shows that amino acid residues $ASp^{429}$ and $ASp^{551}$ are essential to DNA binding, and $Gly^{318}$ and $Gly^{585}$ also affect DNA binding to a certain extent.

• 한국미생물·생명공학회지
• /
• 제18권5호
• /
• pp.490-495
• /
• 1990

토양 분리균인 Bacillus spp.가 생산하는 inulinase를 ammonium sulfate 분획, 열처리, DEAE Sephadex Cl-6B ion exchange chromatography, Sephadex G-100 및 Sephadex G-150 gel 여과 등의 과정을 거쳐 단일 단백질로 분리 정제하였다. 정제 inulinase는 분자량이 약 56,000인 효소로서 pH6.0,$50^{\circ}C$에서 최대 활성을 나타내었으며 $Co^{2+}$와 $Mn^{2+}$에 의해서 현저한 활성화 효과를 보였다. 또한 본 효소는 sucrose와 raffinose에 대해서도 높은 활성을 나타내므로 $\beta$-D-fructofuranosidase(EC 3.2.1.26)로 분류되는 exo-inulinase인 것으로 확인되었다. 한편 효소활성에 필수적인 아미노산 잔기는 tryptophan과 histidine인 것으로 분석되었으며 inulin과 sucrose에 대한 $K_m$값은 각각 $2.0 \times 1.0^[-3}M, 1.0 \times 10^[-2}M$로 산출되었다.

• BMB Reports
• /
• 제32권4호
• /
• pp.358-362
• /
• 1999

dTDP-D-glucose 4,6-dehydratase as an oxidoreductase catalyzes the conversion of dTDP-D-glucose to dTDP-4-keto-6-deoxy-D-glucose, which is essential for the formation of 6-deoxysugars. dTDP-D-glucose 4,6-dehydratase shows remarkable sterochemical convergence in which displacement of the C-6 hydroxyl group by a C-4 hydrogen proceeds intramolecularly with inversion of configuration. The reaction mechanism is known to be oxidation, dehydration, and reduction by bases mediating proton transfer and $NAD^+$ cofactor. In this study, the bases in the active site domain are proposed to be His-79 and His-300 from a comparison of the peptides of the dehydratase and UDP-D-glucose epimerase. His-79 and His-300 were mutated to prepare the mutants H79L (mutation of histidine to leucine at the 79th amino acid) and H300A (mutation of histidine to alanine at the 300th amino acid) by site-directed mutagenesis. The H79L protein was inactive, showing that His-79 participates in the reaction mechanism.

• 한국수산과학회지
• /
• 제12권4호
• /
• pp.235-240
• /
• 1979

krill을 식용화하기 위한 한 방법으로서 paste상 및 분말상의 krill soluble을 가공하고 제품의 구성아미노산 및 유리아미노 리의 조성을 검토하였다. 생동결 krill, 자가소화 및 $0.2\%$의 pronase-p의 첨가후의 가수분해에 의한 paste상과 분말상의 krill solube의 구성아미노산 중에는 glutamic acid, lysinge 및 aspartic acid가 가장 많았으며, cystine과 histidine이 가장 적었다. 생동결 krill의 유리아미노산중에는 lysine, arginine, proline, glycine, alanine 및 leucine이 가장 많았으며, cystine과 histidine 그리고 구성아미노산에서 그 함량이 많던 glutamic acid와 aspartic acid가 가장 적었다. 자가소화에 의한 paste상의 krill soluble의 유리아미노산에서는 생동결 krill에서 보다 glutamin acid, serine threonine, isoleucine, aspartic acid, valine 등의 량이 많아졌으며, 특히 glutamic acid는 거의 40배정도로 증가하였다. 전체적으로는 lysine, leucine, threonine 및 alanine 등이 많았으며 cystine, aspartic acid 및 histidine의 량이 적었다. $0.2\%$의 pronase-p를 첨가하여 가수분해한 paste상의 krill soluble 유리아미노산에는 aspartic acid와 glutamic acid이 량이 자가소화시보다 월등히 큰 증가폭을 보였으며 전체적으로는 lysine, leucine, arginine, alanine 및 proline이 많았으며 cystine, histidine, serine 등의 량이 적었다. 생동결 krill 및 drill soluble의 필수아미노산은 함량면에서 달걀과 비교하여 손색이 없었다.

• 한국해양바이오학회지
• /
• 제10권1호
• /
• pp.18-25
• /
• 2018

Chlorella is quantitatively and qualitatively high in protein with balanced essential amino acid profiles, vitamins and minerals. ${\gamma}-Aminobutyric$ acid (GABA) is broadly distributed in nature and fulfills multi-physiological functions including effect such as a health-promoting functional compound. To improve the GABA production, Chlorella protothecoides were grown through the modified mixtrophic culture medium containing 2L of sterilized bristol medium with 0.01% urea and 4.0% glucose in a 5L fermenter. The results showed that nineteen kinds of amino acid including GABA at C. protothecoides sample were analyzed using high performance liquid chromatography (HPLC). Glutamic acid in total concentration (%) of amino acid is the most abundant amino acid (33.10%), followed by alanine (20.48%) and GABA (17.48%). Three amino acids including GABA were responsible for more than 70% total concentration in C. protothecoides sample including eight essential and nine non-essential amino acids: aspartic acid, asparagine, serine, glutamine, histidine, glycine, threonine, arginine, tyrosine, valine, methionine, tryptophan, phenylalanine, isoleucine, leucine, lysine. As a result of this experiment, it is expected that Chlorella will be developed to a critical product having high value as, GABA, functional food materials.

• 한국작물학회지
• /
• 제41권5호
• /
• pp.521-525
• /
• 1996

본 연구는 우리나라에 자생하는 전조의 근에 대한 조성분, 유리 아미노산, 향기성분 등의 분석을 통하여 향료작물로서의 가능성을 검토하고자 수행하였는 바 얻어진 결과를 요약하면 다음과 같다 1. 전조 뿌리의 조성분가운데 조단백질은 7.69%, 조지방 1.74%, 조섬유 2.44%, 그리고 조회분은 3.76% 였으며 엑스 함량은 27.68%로 나타났다. 2. 유리 아미노산 조성 및 함량에서 종류는 총 16종이었으며 아미노산의 함량에 따른 순위는 phenylalanine>tyrosine>arginine>alanine>glutamic acid>aspartic acid>lysine>isoleucine>proline>glycine>histidine>thereonine>leucine>methionine>valine, serine이었고 유리 아미노산 함량 중 가장 높은 아미노산은 phenylalanlne으로 6.38 mg이었다. 3. 전조의 뿌리에 대한 향기성분은 $\alpha$-pinene, d-1imonene 등의 mono terpene류가 11종이었고 methyl eugenol 등의 phenyl propanoid류가 3종, 기타 8종으로 구성되어 있었으며 식물정유의 수율은 0.58%였다. 4. 종합적으로 볼 때, 한국산 전조에 대한 향료작물로서의 가능성이 있을 것으로 판단되어 금후 향기성분의 수율을 높이기 위한 재배법 연구의 일환으로 차광, 재배거리, 시비량 등의 시험이 필요한 것으로 판단되었다.

• 한국조리학회지
• /
• 제22권6호
• /
• pp.71-77
• /
• 2016

To determine the nutritional value of domestic tomatoes, the levels of amino acids, amino acid metabolites, and the bioactive compound ${\gamma}-aminobutyric-acid$ (GABA) were analyzed in three domestic tomato varieties (Rafito, Momotaro, and Medison). Eighteen free amino acids were found, and total free amino acid content was 3,810.21~4,594.56 mg/100 g (dry weight). L-glutamic acid (L-Glu) was the most abundant amino acid, ranging from 1,866.60 mg/100 g for Momotaro to 2,417.45 mg/100 g for Medison. The next most abundant amino acids were L-glutamine (L-Gln) and L-aspartic acid (L-Asp). The three tomato varieties had a good balance of all the essential amino acids except tryptophan. Total essential amino acid content was 274.26~472.71 mg/100 g (dry weight). The following amino acid metabolites were found: L-carnitine (L-Car), hydroxylysine (Hyl), o-phosphoethanolamine (o-Pea), phosphoserine (p-Ser), ${\beta}-alanine$ (${\beta}-Ala$), N-methyl-histidine (Me-His), ethanolamine (EtNH2),and L-citrulline(L-Cit). Large quantities of GABA were found in all three varieties: 666.95-868.48 mg/100g (dry weight). These results support the use of these tomato varieties as nutritious food materials.

• 한국식품영양학회지
• /
• 제31권3호
• /
• pp.435-440
• /
• 2018

This study analyzed the general components of rice bread with 75% rice content such as water, crude ash, crude protein, crude fat and carbohydrate, and its nutrients such as vitamin C, vitamin A, vitamin E content, minerals, amino acids, and fatty acids. The contents of crude protein were high and those of crude fat were low with the contents of crude ash, crude protein, and crude fat being 1.61, 18.50, 0.04 g/100 g respectively. Vitamin A was not detected and the contents of vitamin C and vitamin E were 3.85 and 3.04 mg/100 g, respectively. The calcium, potassium, magnesium, iron and sodium contents were 222.0, 117.90, 24.12, 2.30, 555.90 mg/100 g respectively. Rice bread contains 9 essential amino acids such as valine, leucine, isoleucine, methionine, threonine, lysine, phenylalanine, histidine, and arginine. The analysis of rice bread fatty acid showed 58.04 mg/100 g of saturated fatty acid, 26.31mg/100 g of monounsaturated fatty acid and 15.64 mg/100 g of polyunsaturated fatty acid. The total essential fatty acid content was 15.49 mg/100 g. With the rising interest in processed rice products, well-being, and diet, it is necessary to develop processed rice foods that are nutritional and low in calories using rice powder that is nutritionally better than flour.