• Applied Biological Chemistry
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• 제38권1호
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• pp.13-19
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• 1995

Phenylalanine 생산시 tyrosine이 부생되지 않도록 tyrA유전자 발현이 낮은 여러 가지 온도조절형 plasmid를 제작하였으며, phenylalanine 생산균주인 대장균 AT2471$[tyrA^-,\;thi^-]$은 tyrosine 영양요구 변이균주이므로 생산배지에 tyro-sine 첨가없이 phenylalanine을 생산할 수 있도록 하기 위하여 tyrosine 복귀변이균주를 분리하여 phenylalanine 생산을 검토하였다. 2.5 l jar fermenter를 사용하여 tyrosine 첨가없이 phenylalanine 생산을 검토하여 대장균 AT2471/pSY146A, 대장균 AT2471 tyrosine 복귀변이균주 5/pSY111-14를 $39^{\circ}C$에서 55시간 배양한 결과 각각 12 g/l, 15 g/l를 생산하였다.

• 대한유전성대사질환학회지
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• 제16권2호
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• pp.86-92
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• 2016

목적: $BH_4$ 부하검사는 PKU와 $BH_4$ 결핍증을 감별하고, PKU 환자 중 $BH_4$ 반응성을 확인할 수 있는 중요한 검사이다. 일반적으로 알려진 프로토콜로 페닐알라닌 부하와 $BH_4$ 부하검사는 환자의 편의 및 입원기간을 단축시킬 수 있는 유용한 검사방법이다. 하지만 페닐알라닌 부하의 용량이나 부하 후 $BH_4$ 투여시간이 임상적으로 적절한지에 대하여는 충분한 연구가 이루어지지 않았다. 본 연구는 순천향대학교 소아청소년과 유전대사 클리닉에 내원한 환자 중 100 mg/kg의 페닐알라닌을 복용 후 $BH_4$ 부하검사를 시행한 6명 환자들의 의무기록을 분석하여 기존의 페닐알라닌 부하 방법의 효용성을 연구하였다. 방법: 2004년 7월부터 2015년 7월까지 순천향대학교 유전대사 클리닉에서 추적관찰하고 있는 총 207명의 환자 중 100 mg/kg의 페닐알라닌을 복용 후 $BH_4$ 부하검사를 시행한 6명 환자들을 대상으로 의무기록을 분석하였다. 이들은 모두 제한식사를 시행하고 있었으며 100 mg/kg의 페닐알라닌을 복용 후 3시간 뒤 20 mg/kg의 $BH_4$를 부하하였다. $BH_4$를 부하한 시점을 Basal로 하여 1, 2, 4, 6, 8, 12, 24시간에 혈중 페닐알라닌 수치를 연속적으로 측정하였다. 결과: 6명의 최고 페닐알라닌 농도의 평균은 $20.0{\pm}11.70mg/dL$ 이었다. 1명은 페닐알라닌 복용 후 7시간 째, 다른 1명은 5시간 째, 나머지 3명은 4시간째에 최고농도에 도달하였다. 3시간 만에 최고 농도에 도달한 환자는 1명이었다. 페닐알라닌 부하 후 페닐알라닌 수치가 $400{\mu}mol/L$ 이상으로 상승한 환자는 6명 중 4명(66%)이었다. 나머지 2명의 환자는 페닐알라닌 수치가 각각 6.1 mg/dL ($366{\mu}mol/L$), 5 mg/dL ($300{\mu}mol/L$)이었다. 결론: 본 연구에서 기존에 알려진 바와 같이 100 mg/kg의 페닐알라닌 복용 후에 3시간째에 최고 농도에 도달한 환자들은 6명 중 1명(16%)이고 $400{\mu}mol/L$ 이상 페닐알라닌 수치가 올라간 환자는 4명(66%)이었다. 일반적으로 알려진 검사 방법으로 페닐알라닌 농도가 $400{\mu}mol/L$ 이상으로 상승하지 않은 환자가 있었고 3시간 보다 더 늦게 최고 농도에 도달하는 단점이 있었다. 따라서 페닐알라닌은 200 mg/kg이상 증량하여 복용하고 적어도 페닐알라닌 복용 4-6시간 후에 $BH_4$ loading을 하는 것이 적절한 진단에 도움이 될 것으로 사료된다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.604-607
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• 2000

Preparation for the D-phenylalanine using chemo-enzymatic reaction was investigated. D,L-5-benzylhydantoin was synthesized chemically from L-phenylalanine and converted to N-carbamoyl-D-phenylalanine by the immobilized hydantoinase. The pH and temperature affected the solubility and racemization rate of benzylhydantoin. The optimal temperature and pH of the process were $50^{\circ}C$, 8.5, respectively and the conversion yield hadn't much difference with the hydantoinase content in 10hrs. This produced N-carbamoyl-D-phenylalanine was transformed chemically into D-phenylalanine.

• Bulletin of the Korean Chemical Society
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• 제15권5호
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• pp.387-390
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• 1994

The conversion of trans-cinnamic acid to phenylalanine using phenylalanine ammonia lyase (PAL) was examined. The optimum concentration of trans-cinnamic acid for the reaction was observed at 100 mM in cells and at 20 mM in cell free extracts, respectively. The production of L-phenylalanine was increased in both experiments as the concentration of ammonia was increased up to 10 M. The optimal pHs for the maximal conversion of trans-cinnamic acid to L-phenylalanine were 9.5 and 9.0 in experiments carried out with cells and with cell free extracts, respectively.

• 미생물학회지
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• 제28권2호
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• pp.169-173
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• 1990

E. coli를 이용하여 L-phenylalanine을 대량 생산하기 위한 재조합 플라스미드 pMW10, pMW11과 pMW 12를 구성하였다. L- Phenylalanine 생산을 위한 유전자 $aroF^{FR}$, $pheA^{FR}$은 E. coli MWEC 101-5 균주로부터 분리하였다. 재조합 플라스미드를 함유하고 있는 E.coli 대사 조절변이주들의 L-phenylalanine 생산생과 안전성을 조사하여 $aroF^{FR}$, $pheA^{FR}$유전자들의 효율을 알아보았다. MWEC 101-5/pMW 11 균주에서는 24.3 g/I의 L-phenylalanine이 생산되었으나, 플라스미드의 안정성은 73.8%였다. 본 균주의 prephemte dehydratase, 고유 활동도는 E. coli K-12에 비하여 26배 증가된 것이다.

• Applied Biological Chemistry
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• 제31권4호
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• pp.376-381
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• 1988

Rhodotorula glutinis IFO 0559에 의한 transcinnamic acid와 암모니아로부터 L-Phenylalanine 생산의 최적 조건을 검토하였다. L-phenylalanine 생산은 반응액으로 200mM transcinnamic acid, 4M $NH_4OH$, 250mM$(NH_4)_2SO_4$, 0.005% cetylpyridiniurn chloride (pH 10.5), 50mg/m1건조균체를 사용하였을 때 최대 생산량을 나타내었다. 비수용성 유기용매중에서 petroleum ether가 가장 효과적인 유기용매이였으며 반응액에 50% 첨가시 가장 효과가 좋았다. 최적 반응조건하에서 12시간 반응후 L-phenylalanine이 21.19생성되었으며, 이때의 trans-cinnamic acid의 전환율은 63.9%이었다.

• 생약학회지
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• 제27권4호
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• pp.359-365
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• 1996

In order to product the saikosaponin which is one of the secondary product from Bupleurum falcatum efficiently through the tissue culture, several levels of agar and gellan gum as the gelling agent, 2,4-D as the growth regulator, and L-phenylalanine as the precursor were used with single or combination treatment on MS basal medium. Gellan gum was more effective than agar as the gelling agent in fresh and dry weight increase of callus induced from Bupleurum falcatum leaf segment. Gellan gum medium supplemented with L-phenylalanine produced 1.6 times of fresh weight more than that of agar. The fresh weight was remarkably high in gellan gum when the calli was treated with the combination of 2,4-D and L-phenylalanine similar to the single treatment of 2,4-D or L-phenylalanine. However, the saikosaponin content in callus was high in gellan gum with the single treatment of L-phenylalanine. Especially, the saikosaponin content in gellan gum supplemented with 1.0mg/L L-phenylalanine was 2 times(2.4 mg/g) higher than that in agar medium supplemented with 0.1 mg/L 2,4-D(0.9 mg/g).

• Asian-Australasian Journal of Animal Sciences
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• 제25권8호
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• pp.1138-1144
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• 2012

This study was conducted to evaluate the efficacy of the dipeptide form of phenylalanine as a new source of amino acid in terms of growth performance and whole-body amino acid composition in comparison to the free form for red seabream (Pagrus major). Fish ($1.46{\pm}0.001g$) were fed four isonitrogenous and isocaloric experimental diets containing 0.7 or 1.4% phenylalanine either in free or dipeptide form. A feeding trial was carried out in three replicates and the fish were fed to apparent satiation for six weeks. At the end of the feeding trial, feed intake of fish was influenced by both phenylalanine form and level and significantly higher values were obtained at an inclusion level of 0.7% and by the use of dipeptide form. However, the other growth parameters did not significantly differ among treatments. Whole-body amino acid compositions revealed no significant changes in concentrations of both essential and non-essential amino acids regardless of the increase in phenylalanine levels or the use of its different forms. The finding in this study indicates that juvenile red seabream can utilize dipeptide phenylalanine as efficiently as free form without any undesirable effects on growth performance or whole-body amino acid composition.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.78-78
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• 2010

The Adsorption structures of phenylalanine on Ge(100) surface have been investigated as a function of coverage using high-resolution photoemission spectroscopy (HRPES) and density functional (DFT) calculation. To converge these experimental and theoretical conclusion, we systematically performed HRCLPES measurements and DFT calculation for various coverage in the adsorption structures of phenylalanine molecules on the Ge(100) surface. In this study, we found two different adsorption structure as a function of coverage in phenylalanine on Ge(100), monitoring three core level spectra (Ge 3d, C 1s, N 1s, and O 1s) using HRPES Through analysis of the binding energies, we confirmed that O-H dissociated and N dative-bonded structure emerges at low coverage (0.10 ML), which is the same to the result of glycine and alanine on Ge(100) system, whereas O-H dissociation structure also appears at higher coverage. Moreover, we observed the shape of phenyl group being included in phenylalanine is changed from flat to tilting structure at final state using DFT calculation. Through the spectral analysis for phenylalanine, we will demonstrate variation of coverage dependent structural change for phenylalanine on Ge(100) surface using experimental (HRPES) and theoretical studies (DFT calculation).

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.205-205
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• 2011

The self-assembly of ${\gamma}$-phenylalanine on Au(111) at 150 K was investigated using scanning tunneling microscopy (STM). Phenylalanine can potentially form two-dimensional (2D) molecular networks through hydrogen bonding (through the carboxyl and amino groups) and ${\pi}-{\pi}$ stacking interactions (via aromatic rings). We found that ${\gamma}$-phenylalanine molecules self-assembled on Au(111) surfaces into well-ordered structures such as ring-shaped clusters (at low and intermediate coverages) and 2D molecular domains (intermediate and monolayer coverages), whereas ${\alpha}$-phenylalanine molecules formed less-ordered structure on Au(111). The self-assembly of ${\gamma}$- but not ${\alpha}$-phenylalanine may be related to the flexibility of the carboxyl and amino groups in the molecule. Moreover, as expected, the 2D molecular network of ${\gamma}$-phenylalanine on Au(111) was mediated by a combination of hydrogen bonding and ${\pi}-{\pi}$ stacking interactions.