• Journal of Nutrition and Health
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• 제4권4호
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• pp.39-46
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• 1971

Iso-butyl bromide의 합성을 시작으로 D.L-1-amino-3-methylbutylphosphonic acid의 합성을, Diethyl phophite의 합성을 시작으로 D.L-1-amino-2-phenyl ethylphosphonic acid의 합성을 하였다. 합성되어진 필수 아미노산인 Isoleucine analogue phosphonic acid는 각각 0.2%, 0.4%를 식이에 첨가했고 Phenylalanine analogue phosphonic acid는 0.35%와 0.7%를 각각 첨가하였으며 Standard-1과 Standard-2군과 비교군인 Isoleucine 0.2%와 0.4% Phenylalanine 0.35%와 0.7%군으로써 총 100마리의 숫쥐로 각 7주씩 14주의 사육 실험을 하였다. 동물 사육 기간내의 뇨채취와 사육후의 각 장기의 채취로써 총 질소와 P, glycogen측정을 시도하였다. 이러한 일련의 실험결과 (1) D.L-1-amino-3-methylbuthylphosphonic acid나D.L-1-amino-2-phenylethylphosphonic acid의 유기 합성에 있어서는 다 수율이 낮고 상당히 높은 융점을 보였으며 ${\alpha}-NH_2$기가 Ninhydrin 반응에 예민했다. (2) Aminophosphonic acid의 첨가군(D.L-1-amino-3-methylbutyl phosphonic acid, D.L-1-amino-2-Phenylethylphosphonic acid)에서나 Amino acid(Isoleucine, Phenylalanine)첨가군에 있어서 모든 장기의 무게, 총체내질소 보유율, 간장내 총단백질량과 인의양, 및 뇨를 통한 인의 배설량에 각각 큰 차이를 보이지 않았다. 이로 보아서 Phenylalanine Aminophosphonic acid나 Isoleucine aminophosphonic acid가 다 보통 아미노산인 Isoleucine이나 Phenylalanine에 못지않게 체내에서 이용됨이 밝혀졌다. (3) 그러나 Phenylalanine aminophosphonic acid 첨가군이 간의 glycogen 함량에 있어서 Phenylalanine 첨가군과 Standard군과 비교해 보았을때 높았으며 이는 통계적인 유의성을 나타냈다.(<0.05) 이는 Phenylalanine Aminophosphonic Acid가 active state로써 간내에서 쉽게 이용되어서 Tricarboxylic cycle의 intermediate로 incorporate되는 경향으로 생각 할 수 있다.

• 한국식품영양과학회지
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• 제33권6호
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• pp.1017-1021
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• 2004

Thr, Trp을 overproduce하는 효모 균주를 분리하기 위하여 Sacchromyces cerevisiae를 UV와 EMS로 mutagenesis한 후 screen하였다. Thr analogue인 hydroxynorvaline이 UV mutagenesis 후 Thr overproducing 하기 위해 사용되었다. 31 mutant 중 아미노산 분석 결과에 의해 TC 5-1이 선정되었고 다시 Trp overproducing 위해 EMS mutagenesis 하였다. 8개의 mutant가 flurotryptophan을 이용하여 Thr, Trp을 overproduce하는 mutant로 선정되었다. 아미노산결과에 의해 그 중 TC 6-1이 최종 효모 균주로 선정되었다.

• 대한화학회지
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• 제5권1호
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• pp.38-41
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• 1961

By varying groups on biologically active molecules, it is possible to produce analogues which sometimes inhibit the action of the parent compound. Such is true of taurine(${\beta}$-amino-ethane sulfonic acid)as an analogue of ${\beta}$-alanine and of pantoyl taurine for pantothenic acid. It seemed possible that the sulfonic acid analogues of amino acids built into peptides might possibly produce inhibition of the parent peptide. Tauryl-L-histidine was selected to prepare as an analogue of carnosine(${\beta}$-alanyl-L-histidine). There were several reasons for this choice. Camosine causes a slight contraction of isolated uterine muscle and inhibition of this action can be easily tested. Also, taurine, being a ${\beta}$-amino sulfonic acid, is much more stable than the ${\beta}$-amino sulfonic acids. Phthalyl tauryl-L-histidine methyl ester was prepared by condensing phthalyl tauryl chloride with histidine methyl ester in chloroform. The yields were quite low possibly due to reaction between the acid chloride and the imidazole of histidine. Approximately 50 per cent yield of crude amorphous product was obtained, but upon purification by crystallization they yielded only 25 percent of a pure product. The methyl ester was removed by acid hydrolysis to prevent partial cleavage of the phthalyl group. Crystalline tauryl histidine was then obtained from this acid by removal of the phthalyl group by hydrazinolysis. Tests for inhibition were carried out by comparing the action of camosine on isolated uterine muscle before and after tauryl histidine had been added to the bath surrounding the muscle strip. Only in very high relative concentrations of tauryl histidine was there any demonstrable inhibition.

• Journal of Microbiology and Biotechnology
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• 제7권5호
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• pp.341-344
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• 1997

Batch cultures of Anacystis nidulans BD-1 resistant to azaleucine and fluorotyrosine produced and liberated a wide range of amino acids, notably glutamic acid, alanine, phenylalanine, leucine, isoleucine, cysteine and methionine. Sustained liberation for prolonged periods was achieved after immobilization on calcium alginate and the net concentration in the medium was 0.18-0.2 g $I^{-1}$. While acetohydroxy acid synthase in azaleucine-resistant mutant lost leucine- and isoleucine-sensitivity, fluorotyrosine-resistant strain turned phenylalanine activating. The activities of nitrate assimilating enzymes were also higher in the mutants and were relaxed from ammonium-repression. The metabolic adjustments involved in amino acid overproduction are discussed.

• Bulletin of the Korean Chemical Society
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• 제27권8호
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• pp.1194-1198
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• 2006

For the purpose of developing more effective chelating agents, we have synthesized a diethylene triamine pentaacetic acid(DTPA) analogue by using an amino acid. S-(N-Boc-aminophenyl)-Cys(t-Bu4-DTPA) methylester was prepared in 6 steps with total yield of 47.9%. For the sake of introducing a biomolecule to the DTPA derivative, a selective hydrolysis was performed with 3 M HCl/Ethylacetate = 1 : 3 ($25{^{\circ}C}$, 30 min, vigorous stirring). $^{166}Ho$-Cys-DTPA and $^{166}Ho$-Biotin-Cys-DTPA were prepared by mixing $^{166}Ho$ with DTPA derivatives at room temp in a HCl solution (pH = 5) and the radiochemical stabilities (> 99%) were maintained for over 6 hrs in vitro.

• Bulletin of the Korean Chemical Society
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• 제13권3호
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• pp.311-314
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• 1992

A new monocyclic ${\beta}-lactam$ analogue, sodium (3R,4S)-3-[2-(2-aminothiazol-4-yl)-(Z)-2-methoxyi minoacetamido]-4-methoxymethyl-2-azetidinone-1- sulfonate (3) was synthesized from L-aspartic acid. Starting from L-aspartic acid, (S)-1-benzyl-4-benzyloxycarbonyl-2-azetidinone (7) was synthesized in four steps by following the established procedures and converted into (3R,4S)-3-amino-1-t-butyldimethylsilyl-4-methoxym ethyl-2-azetidinone (13) in six steps. Acylation of the amino group of 13 with $2-amino-{\alpha}$ -(methoxyimino)-4-thiazoleacetic acid, desilylation, and sulfonation with sulfur trioxide-pyridine complex followed by ion exchange afforded sodium (3R,4S)-3-[2-(2-aminothiazol-4-yl)-(Z)-2-methoxyi minoacetamido]-4-methoxymethyl-2-azetidinone-1- sulfonate (3). Antibacterial activities of this ${\beta}$ -lactam compound 3 were, however, found to be quite low compared to cefotaxime.

• Journal of Microbiology
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• 제33권2호
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• pp.142-145
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• 1995

The pumb gene encoding a basic amino acid transport protein in Neurospora crassa could be cloned by using a mutant strain defective in pmb gene as a host strain, using a negative selection on the media containing amino acid analogue canavanine. To select positive transformants of the genes for cloning, an auxotrophic marker (his-2) was added to a pmb mutant strain by mating ; a triple mutant (pmn : pmb : his-2) was constructued by crossing a strain defective in basic amino acid transport system (# 1683-bat um 535 "A") to a double mutant strain defective in neutral amino acid transport and histidine production (mitrol : his-2 "a"). Crossing was performed on synthetic crossing (SC) media containing histidine. The pmn : pmb and pmn :pmb : his-2 strains were selected among the progeny colonies from crosses on plates containing 5- .mu.g/ml para-fluoro-phenylalanine (PFPA), 200 .mu.g/ml canavanine, and 500 .mu.g/ml histidine. The selected colonies were cultured on minimal media with or without histidine for discarding pmn : pmb strain, because the pmn : pmb : his -2 strain grows only on histidine containing media. The pmn :pmb : his-2 strain selected can be used as a host strain for the cloning of the pmb and the pmn genes from a Neurospora genomic library by means of positive selections.

• Bulletin of the Korean Chemical Society
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• 제35권7호
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• pp.2186-2188
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• 2014

• BMB Reports
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• 제32권1호
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• pp.12-19
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• 1999

Gaegurin 4 (GGN4), a broad-spectrum antibiotic, is a 37-amino acid peptide isolated from the Korean frog, Rana rugosa. In this study, we have chemically synthesized and purified GGN4 analogues where the C-terminal portion is truncated and/or substituted with tryptophan. These peptides show significantly different biological activities depending on the location of tryptophan and the number of amino acids truncated from the C-terminal end. While deletion of 9 amino acids from the C-terminal seems to be marginally tolerable in maintaining the antimicrobial activity, further deletion of up to 14 amino acid residues decreases the potency by more than 60-fold towards Gram-positive, and 10-fold towards Gram-negative, bacteria. Surprisingly, the reduced activity of the shorter peptide can be completely restored by a single substitution of aspartic acid 16 to tryptophan 16 (D16W). Also, the truncation seems to decrease the specificity of antibiotic activity more towards Gram-positive than towards Gram-negative bacteria studied. These data suggest a partial role of the C-terminal region in determining the binding specificity and the activity of peptides upon binding to their target cell membranes.

• Preventive Nutrition and Food Science
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• 제9권2호
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• pp.187-189
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• 2004

To isolate a mutant strain which overproduces tryptophan, mutants of Candida rugosa were screened after EMS (ethyl methane sulfonate) mutagenesis. Fluorotryptophan, a tryptophan analogue, was used for selection of a tryptophan-overproducing mutant after mutagenesis. Among 50 mutants, several candidates were selected based on intracellular tryptophan content. Amino acid analysis results showed that C3 was the best strain because it had the highest amount of tryptophan among the mutants.