Polyamine Stimulation of arcA Expression in Escherichia coli

이문수,김영식,SeonYoungPark,MyungHunChoi,BoMinKim,SeongUkKang,KuiJooLee,이종호 한국미생물학회 2002 The journal of microbiology Vol.40 No.4

The effects of two natural polyamines (putrescine and spermidine) on the synthesis of ArcA, a response regulator of the Arc two-component signal transduction system, were studied using an E. coli mutant deficient in polyamine biosynthesis. Endogenous polyamine deficiency of the mutant resulted in marked reduction in the ArcA level determined by Western blot analysis. Putrescine supplement to the growth medium effectively increased the ArcA level of the mutant in a concentration-dependent manner. Spermidine also stimulated the ArcA level in the mutant to a greater degree than putrescine. Expression of arcA'::lacZ operon fusion in the mutant was stimulated 6-fold and 10-fold by putrescine and spermidine at a 1mM concentration, respectively, indicating that the stimulatory effect of the polyamines on ArcA synthesis is due to transcriptional induction, and that spermidine is a more potent arcA inducer than putrescine. The polyamine-dependent arcA'::lacZ induction was growth-phase-dependent and independent of either arcA or fnr which are two regulators involved in anaerobic stimulation of the ArcA level. These results suggested that putrescine and spermidine polyamines may be potential intracellular signal molecules in the control of arcA expression, and thereby may play an important role in cellular metabolism. The effects of two natural polyamines (putrescine and spermidine) on the synthesis of ArcA, a response regulatorof the Arc two-component signal transduction system, were studied using an E. coli mutant deficientin polyamine biosynthesis. Endogenous polyamine deficiency of the mutant resulted in markedreduction in the ArcA level determined by Western blot analysis. Putrescine supplement to the growthmedium effectively increased the ArcA level of the mutant in a concentration-dependent manner. Spermidinealso stimulated the ArcA level in the mutant to a greater degree than putrescine. Expressionof arcA'::lacZ operon fusion in the mutant was stimulated 6-fold and 10-fold by putrescine and spermidineat a 1mM concentration, respectively, indicating that the stimulatory effect of the polyamineson ArcA synthesis is due to transcriptional induction, and that spermidine is a more potent arcAinducer than putrescine. The polyamine-dependent arcA'::lacZ induction was growth-phase-dependentand independent of either arcA or fnr which are two regulators involved in anaerobic stimulation ofthe ArcA level. These results suggested that putrescine and spermidine polyamines may be potentialintracellular signal molecules in the control of arcA expression, and thereby may play an important rolein cellular metabolism.

도파관-마이크로스트립간의 트랜지션 설계

이문수 한국통신학회 1990 韓國通信學會論文誌 Vol.15 No.9

U-대역 MMIC 전력증폭기 특성 측정에 사용될 도파관-마이크로스트립간의 트랩지션을 설계 제작하였다. 광대역 정합특성을 얻기 위해 릿지 도파관을 사용한 ${\lambda}$/4 Tchebyscheff 임피던스 변환기를 트랜지션 임피던스 변환부에 적용하였다. 설계된 Transition은 Supper-Compact을 사용하여 40GHZ-48GHZ 대역에서 Su이 -28dB 이하가 되도록 최적설계하였다. 40GHZ-47GHZ 범위에서 측정된 Transition Insertion Loss는 약 0.3dB Return Loss는 25dB 로 나타났다. A comppact waveguide to microstrip transition to be used for measurements of the performances of the U-band MMIC power amplifier is designed and fabricated. A Tchebyscheff ${\lambda}$/4 impedence transformer is adopted as an impedence converter of the transition. The designed transition is optimized to get Su less then -28dB over the 40-to-48GHZ band using Supper Compact program. The measured results shows that insertion loss and return loss are typically 0.3 and 25dB respectively over 40-to-47GHz.

구형 마이크로 스트립 소자를 이용한 GP여파기 설계에 관한 연구 ( A Study on the Design of GP Filters Using Rectangular Microstrip Elements )

이문수,이상설 대한전자공학회 1984 대한전자공학회 학술대회 Vol.1984 No.1

준 대수 주기형 광대역 마이크로스트립 안테나 설계 ( Design of wideband Quasi-log periodic Microstrip Antenna )

이문수,이상설 대한전자공학회 1982 대한전자공학회 학술대회 Vol.1982 No.1

Cis-9-Octadecenoic acid와 trans-9-Octadecenoic acid의 열분해에 관한 연구

이문수,이운철,곽재진,Lee, Moon-Soo,Lee, Un-Cheoul,Kwag, Jae-Jin 한국연초학회 1987 한국연초학회지 Vol.9 No.1

The pyrolysis of geometrical isomers of 9-octadecenoic acid were conducted at $600^{\circ}C$ under nitrogen, and its pyrolytic behaviors were investigated. The pyrolytic products of both fatty acids, cis-9-octadecenoic acid(oleic acid) and trans-9-octadecenoic acid(elaidic acid), were analyzed using a gas chromatograph and GC/MS spectrometer. Twenty-seven different compounds were identified from these pyrolyzates, and the chief products of them were ketones, alcohols and aromatic hydrocarbons. And also, the pyrolytic mechanisms of two geometrical isomers of this fatty acid were discussed by a comparison of experimental results.

Glycyrrhizic acid 와 Glycyrrhetinic acid의 열분해에 관한 연구

이문수,김옥찬 한국연초학회 1986 한국연초학회지 Vol.8 No.2

The Pyrolytic behavior of glycyrrhizic acid and glycyrrhetini c acid, which are natural flavorants for manufactured cigarettes was observed to find its contribution to the smoke composition. Pyrolyzates of them at 800t were identified using a gas chromatography and a mass spectrometer. According to the analysis of the pyrolytic Products, 43 different compounds were identified Among them the aromatic hydrocarbon compounds were found to be the major products.

담배연기 응축물중 phenolic fraction의 분리와 확인

이문수,임흥빈,장기철,Rhee, Mun-Su,Lim, Heung-Bin,Jang, Ki-Cheol 한국연초학회 1988 한국연초학회지 Vol.10 No.1

The phenolic compounds were isolated from the cigarette smoke condensate using two immiscible organic solvents by a partition coefficient. Of them, 20 phenolic compounds were identified by GC and GC/MS. The amount of the phenolic compounds was phenol, p-crestol, hydroxybensoic acid in order. And there was no difference in composition of these compound dependent on leaf tobacco . About 70% amount of these compounds were absorbed to cellulose acetate filter used. The contents and composition of these compounds were various in the commercial cigarette.

멘톨담배의 $\ell$-Menthol 이행에 관한 연구

이문수,임흥빈,조시형,김성한,박영수 한국연초학회 1989 한국연초학회지 Vol.11 No.1

A study was made of the puff-by-puff delivery of menthol and tar for several commercial brands. The purpose of this study is for the brands constantly to maintain fresh aroma of menthol till the last puff in smoking. The results from this study could be used for development and evaluation of a mentholated cigarette. Prior to the purpose, a straightforward method from extraction through quantitative analysis of 9-menthol contained in cigarettes has been developed.

Gas Chromatography에 의한 잎담배와 담배연기응축물 중의 유기산 정량

이문수,이운철,오세열,이규서 한국연초학회 1983 한국연초학회지 Vol.5 No.1

A gas chromatographic procedure is described which permits seperation and determination of nonvolatile organic acids and higher fatty acids simultaneously in tobacco leaves and cigarette smoke condensate. The transfer rates from cigarettes to main stream smoke were examined for eight of the nonblending cigarettes. Average transfer rates for three varieties tobacco leaves, respectively were linolenic 31 and 62% linoleic 21 and 59% palmitic 29 and 38% malic 4 and 6%. Gas Chromatography를 이용하여 잎담배와 연기응축물 중의 비휘발성유기산과 지방산을 정량 분석하였다. 특히 이들 유기산들은 단엽담배일 때 주류연으로 이행율을 조사하였는 바 linolenic acid, 31~62%, linoleic, 21~59% palmitic 29~38%, malic acid 4~6% 정도의 이행율을 보였다.

황색종 잎담배의 건조과정중 비휘발성 유기산과 지방산의 변화에 관한 연구

이문수,이운철,Rhee, Moon-Soo,Lee, Un-Chul 한국연초학회 1982 한국연초학회지 Vol.4 No.2

During the process of curing of the tobacco (Nicotiana tabacum L. ) leaves the concentration change of Nonvolatile organic acids and Higher fatty acids of the flue-cured tobacco leaves was observed. The contents of Nonvolatile organic acids in flue-cured tobacco leaves were as follows, malic> oxalic>malonic>citric>succinic acid. Higher fatty acids was linolenic>Palmitic>oleic >stearic$\geqq$linoleic acid, Citric acid content of last curing time was increased about 4~5 times in compare to before curing tobacco. It was concluded that significant changes of three variety flue-cured tobacco but a significant difference was observed in the composition of Daegu gold variety.