• 제목/요약/키워드: histidine

검색결과 982건 처리시간 0.022초

Histidine 및 Histamine의 N-carbethoxy 유도체 형성시 수종의 수산기함유 아미노산의 치환 에스터화작용에 대하여 (Transesterification of O, N -bistrifluoroacetyl, n-butyl esters of some hydroxylated amino acids into O-carbethoxy, N-trifluoroacetyl, n-butyl esters during N-carbethoxy derivatization of histidine and histamine)

  • 조도현;제이데그레;피파디여
    • Applied Biological Chemistry
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    • 제20권1호
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    • pp.130-135
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    • 1977
  • 가스 크로마토와 가스크로마-토질량분석기에 의하여 수종의 수산기 함유 아미노산의 치환에 스터화반응을 고찰하고 이들의 fragmentation기작을 설명 했다.

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Chemical Modification of Yeast Farnesyl Protein Transferase Expressed in E. coli

  • Kim, Hyun-Kyung;Yang, Chul-Hak
    • Bulletin of the Korean Chemical Society
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    • 제27권4호
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    • pp.529-534
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    • 2006
  • Chemical modification of the S. cerevisiae farnesyl protein transferase (FPT) with CMC, phenylglyoxal and DEPC resulted in enzyme inactivation, depending upon the reagent concentration. The peptide substrate GST-PEP-I, a GST-fused undecapeptide mimicking the C-terminus of $p21^{Ki-ras}$, protected the enzyme against inactivation by CMC which is specific to either aspartate or glutamate, while the other substrate farnesyl pyrophosphate (FPP) showed protection against phenylglyoxal which is the specific modifier of arginine residues, dependent on the substrate concentrations. Neither of the two substrates protected the enzyme against histidine inactivation by DEPC. It is suggested that there is at least one aspartate or glutamate residue at the peptide substrate binding site, and that at least one arginine residue is located at the binding site of FPP. There also seems to be at least one histidine residue which is critical for enzymic activity and is exposed toward the bulk solution, excluded from the substrate binding sites.

Differential Effects of Cysteine and Histidine-Capped ZnS:Mn Nanocrystals on Escherichia coli and Human Cells

  • Kong, Hoon-Young;Kim, Song-Yi;Byun, Jong-Hoe;Hwang, Cheong-Soo
    • Bulletin of the Korean Chemical Society
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    • 제32권1호
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    • pp.53-58
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    • 2011
  • Cysteine and histidine-capped water-dispersible ZnS:Mn nanocrystals (ZnS:Mn-Cys and ZnS:Mn-His) were synthesized and their effects on E. coli and human cells were investigated. Particle sizes of these nanocrystals were found from HR-TEM images to be 3.5 nm and 4.0 nm, respectively. Their solution photoluminescence spectra showed identical broad emission peaks at 580 nm. ZnS:Mn-His significantly suppressed the growth of E. coli at $100{\mu}g/mL$ and 1 mg/mL concentrations, something not observed with ZnS:Mn-Cys. Consistent with this, greater inhibition of cell proliferation and viability were observed in HEK293 and IMR90 cells in ZnS:Mn-His at $100{\mu}g/mL$ and 1 mg/mL concentrations.

Role of the Amino Acid Residues in the Catalysis of Catechol 2,3-dioxygenase from Pseudomonas putida SU10 as Probed by Chemical Modification and Random Mutagenesis

  • Park, Sun-Jung;Park, Jin-Mo;Lee, Byeong-Jae;Min, Kyung-Hee
    • Journal of Microbiology
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    • 제35권4호
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    • pp.300-308
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    • 1997
  • The catechol 2,3-dioxygenase (C23O) encoded by the Pseudomonas putida xylE gene was over-produced in Escherichia coli and purified to homogeneity. The activity of the C23O required the reduced form of the Fe(II) ion since the enzyme was highly susceptible to inactivation with hydrogen perocide but reactivated with the addition of ferrous sulfate in conjunction with ascorbic acid. The C23O activity was abolished by treatment with the chemical reagents, diethyl-pyrocarbonate (DEPC), tetranitromethane (TNM), and 1-cyclohexy1-3-(2-morpholinoethyl) car-bodiimidemetho-ρ-toluenesulfontate (CMC), which are modifying reagents of histidine, tyrosine and glutamic acid, respectively. These results suggest that histidine, tyrosine and glutamic acid residues may be good active sites for the enzyme activity. These amino acid residues are conserved residues may be good active sites for the enzyme activity. These amino acid residues are conserved residues among several extradion dioxygenases and have the chemical potential to serveas ligands for Fe(II) coordination. Analysis of random point mutants in the C23O gene derived by PCR technique revealed that the mutated positions of two mutants, T179S and S211R, were located near the conserved His165 amd Hos217 residues, respectively. This finding indicates that these two positions, along with the conserved histidine residues, are specially effective regions for the enzyme function.

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국내 어류에서 분리된 Megalocytivirus의 유전형 분류 및 상관관계 분석 (Genetic relatedness of Megalocytivirus from diseased fishes in Korea)

  • 이은선;조미영;민은영;정승희;김광일
    • 한국어병학회지
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    • 제32권2호
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    • pp.49-57
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    • 2019
  • 본 연구에서는 2012년부터 2018년 1월까지 국내 어류에서 참돔이리도바이러스병 (red sea bream iridoviral disease; RSIVD) 으로 확정 진단된 주요 분리주에 대하여 major capsid protein (MCP) 유전자의 염기서열을 바탕으로 Megalocytivirus의 유전적 관계를 명확히 했다. 또한, Megalocytivirus와 숙주 세포간 상호작용에 영향을 줄 수 있는 특이 유전자 2종, Vascular endothelial growth factor (VEGF) 및 Histidine triad motif인 HIT-like 단백질 (HIT)에 대한 염기서열 분석을 통해 유전적 상관관계를 고찰하였다. 국내 어류에서 분리된 39개의 megalocytiviruses는 2가지 유전형인 red sea bream iridovirus (RSIV)형과 turbot reddish body iridovirus (TRBIV)형으로 분류되었으며, RSIV형의 megalocytiviruses는 다시 유전아형인 RSIV-subgroup 1형과 2형으로 분류되었다. 그리고 VEGF 유전자 염기서열 분석 결과에서는 RSIV형의 바이러스에서 변이가 발생되었음을 확인할 수 있었으며, HIT-like 단백질 유전자는 RSIV형의 Megalocytivi rus에서만 발견되는 것을 알 수 있었다.

Chemical Modification of 5-Lipoxygenase from the Korean Red Potato

  • Kim, Kyoung-Ja
    • BMB Reports
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    • 제33권2호
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    • pp.172-178
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    • 2000
  • The lipoxygenase was purified 35 fold to homogeneity from the Korean red potato by an ammonium sulfate precipitation and DEAE-cellulose column chromatography. The simple purification method is useful for the preparation of pure lipoxygenase. The molecular weight of the enzyme was estimated to be 38,000 by SDS-polyacrylamide gel electrophoreses and Sepharose 6B column chromatography. The purified enzyme with 2 M $(NH_4)_2SO_4$ in a potassium phosphate buffer, pH 7.0, was very stable for 5 months at $-20^{\circ}C$. Because the purified lipoxygenase is very stable, it could be useful for the screening of a lipoxygenase inhibitor. The optimal pH and temperature for lipoxygenase purified from the red potato were found to be pH 9.0. and $30^{\circ}C$, respectively. The Km and Vmax values for linoleic acid of the lipoxygenase purified from the red potato were $48\;{\mu}M$ and $0.03\;{\mu}M$ per minute per milligram of protein, respectively. The enzyme was insensitive to the metal chelating agents tested (2 mM KCN, 1 and 10mM EDTA, and 1 mM $NaN_3$), but was inhibited by several divalent cations, such as $Cu^{++}$, $Co^{++}$ and $Ni^{++}$. The essential amino acids that were involved in the catalytic mechanism of the 5-lipoxygenase from the Korean red potato were determined by chemical modification studies. The catalytic activity of lipoxygenase from the red potato was seriously reduced after treatment with a diethylpyrocarbonate (DEPC) modifying histidine residue and Woodward's reagent (WRK) modifying aspartic/glutamic acid. The inactivation reaction of DEPC (WRK) processed in the form of pseudo-first-order kinetics. The double-logarithmic plot of the observed pseudo-first-order rate constant against the modifier concentration yielded a reaction order 2, indicating that two histidine residues (carboxylic acids) were essential for the lipoxygenase activity from the red potato. The linoleic acid protected the enzyme against inactivation by DEPC(WRK), revealing that histidine and carboxylic amino acids residues were present at the substrate binding site of the enzyme molecules.

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한국(韓國) 주류성분(酒類成分)에 관(關)한 연구(硏究) (제2보(第2報)) -Paper Chromatography에 의(依)한 탁주중(濁酒中)의 유리(遊離) Amino 산(酸)의 검색(檢索)- (Studies on the Components Korean Sake (Part 2) -Detection of the Free Amino Acids in Takju by Paper Partition Chromatography-)

  • 김찬조
    • Applied Biological Chemistry
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    • 제9권
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    • pp.59-64
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    • 1968
  • 1. 국자(?子)를 사용(使用)하여 백미(白米) 및 옥수수를 원료(原料)로 탁주(濁酒)를 담금하고 경시적(經時的)으로 그 발효(醱酵)술덧중(中)의 Amino-N를 Formol 법(法)으로 정량(定量)하고 또한 유리(遊離) Amino 산(酸)을 PPC 법(法)으로 검출(檢出).하였다. 2. 백미정료탁주(白米定料濁酒)술 덧 중(中)에서는 Aspartic acid, Cystine Glutamic acid, Glycine, Serine Alanine, Tyrosine, Histidine, Valine, Tryptophan, Phenylalanine, Proline 및 Leucine 등 14종의 Amino 산(酸)을 검출(檢出)하였다. 3. 옥수수원료탁주(原料濁酒)술덧 중(中)에서는 Aspartic acid, Cystine, Glycine, Derine, Alanine, Lysine, Valine, Aistididine, Proline, Leucine 및 Tryptophan 등(等) 12종(種의) Amino 산(酸)을 검출하였다. 4. 백미(白米) 및 옥수수원료(原料) 탁주중(濁酒中)의 주체 Amino 산(酸)은 Paper Chromatography에 나타난 각(各) Spot의 정색도(呈色度)로 보아 Lysine, Valine, Leucine, Serine, Proline 및 Glycine 등(等)으로 추정(推定)하였다.

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가열시간별 가물치육 엑스중의 아미노산 및 그 관련화합물의 변화 (Effect of Heating Time on Contents of Amino Acids and Related Compounds in the Muscle Extract of Snakehead)

  • 한영실;김경진;변재형
    • 한국수산과학회지
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    • 제19권2호
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    • pp.141-146
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    • 1986
  • 엑스성분에 대하여 비교적 알려진 것이 적은 담수어 중 가물치를 시료로 하여 가열 시간별로 육액스분중의 아미노산 및 그 관련화합물의 함량변화를 분석 검토하였다. 가물치의 생육중에는 glycine, taurine, glutamic acid, histidine이 특히 많은 함량을 보였고, 요소가 많이 함유되어 있는 것도 특기할 점이었다. 전술한 4 가지 성분이 전체아미노산 및 그 관련화합물중 약$53\%$를 차지하였다. 가열시간에 따른 전질소엑스분의 양적 변화를 측정한 결과, 대체로 가열 120분까지는 대폭 증가하였으나 그 이후부터는 감소하는 관계를 보였다. 120분간의 가열에서 특히 현저한 증가를 보인 성분은 요소를 비롯하여 taurine, glycine, alanine, hydroxyproline, ${\beta}$-aminoisobutyric acid 등이었다. 엑스분을 가수분해한 결과, 일부의 성분은 증가하였으며, ethanolamine, lysine, 1-methylhistidine, phenylalanine, glutamic acid, taurine 등은 현저한 증가경향을 보였다.

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