• 한국군사과학기술학회지
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• 제9권4호
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• pp.32-38
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• 2006

In this paper a sequence estimator of CDMA communication system is suggested. A sequence estimator uses Galois Field operation. A sequence estimator can provide another CDMA pilot signal which is un-modulated spreaded signal. A estimated sequence signal and received signal have no correlation. Tow signals can be summed using MRC(maximal ratio combine) method. The stronger signal can be added as a larger ratio, but the weaker signal can be added as a smaller ratio. We can distinguish strong signal using SNR estimator. Therefore it is possible to receive an additional pilot signal, and to support more reliable communications by using sequence estimator.

• 한국미생물·생명공학회지
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• 제26권1호
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• pp.68-75
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• 1998

A. niger의 GOD(Glucose Oxidase) 대량생산과 효율적인 분비를 protein의 대량생산에 많이 사용되는 strain인 S. cerevisiae에서 시도하였다. S. cerevisiae의 ADH1과 GAL 10 promotor, 그리고 ${alpha}$-MF signal sequence와 A. oryzae의 ${alpha}$-amylase signal sequence 및 S. cerevisiae의 GAL7과 A. niger의 GOD terminator를 이용하여 4개의 expression vector를 합성한 후 S. cerevisiae 2805에 auxotroph 방법으로 형질변환시켰다. 변이체들을 배양하여 세포내와 세포외의 GOD활성도를 분석한 결과 GAL 10 promotor가 삽입된 pGAL변이체들이 ADH1 promotor가 삽입된 pADH 변이체들 보다 GOD 생산성이 높았다. GAL 10 promotor와 A. oryzae의 ${alpha}$-amylase signal sequence가 삽입된 pGALGO2에서 115시간 배양시 GOD의 생산이 가장 높았다($GOD_{total}$: 10.3 unit/mL, $GOD_{ex}$: 8.7 unit/mL). 이 수치는 같은 promotor인 GAL 10 promotor와 ${alpha}$-MF signal sequence가 삽입된 pGALGO1보다 3배정도 높다. 이 결과는 ADH 1 promotor를 사용하였을 경우에도 일치하였다. 또한 A. oryzae의 ${alpha}$-amylase signal sequence가 S. cerevisiae의 ${alpha}$-MF signal sequence보다 GOD를 더 효과적으로 분비시켰다. 상기 결과로 미루어 보면 signal sequence가 단백질의 분비 외에도 단백질 합성에도 많은 영향을 주는 것으로 추측된다. pGALGO1과 pGALGO2의 GOD분비효율은 각각 89%, 84%이었다. S. cerevisiae에서는 일반적으로 과당화가 일어나기 때문에 S. cerevisiae에서 합성된 재조합 GOD의 분자량은 250 kDa으로 A. niger의 GOD(170 kDa)보다 더 컸다.

• 한국경영과학회지
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• 제24권2호
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• pp.69-80
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• 1999

A genetic algorithm to determine the optimal signal sequence and double cycle pattern is described. The signal sequence and double cycle pattern are used as the input for TRANSYT to find optimal signal timing at each junction in the area traffic networks, In the genetic process, the partially matched crossover and simple crossover operators are used for evolution of signal sequence and double cycle pattern respectively. A special conversion algorithm is devised to convert the signal sequence into the link-stage assignment for TRANSYT. Results from tests using data from an area traffic network in Leicester region R are given.

• The Plant Pathology Journal
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• 제15권6호
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• pp.313-318
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• 1999

Cloning of the 5'untranslated region (5' UTR) and Nterminus of the glycoprotein precursor (G2G1) open reading frame of tomato spotted wilt virus has been problematic, possibly because of the toxicity of a signal peptide at the beginning of th G2G1 protein precursor. The toxicity of the signal peptide to bacterial growth and the reason for the expression of the peptide gene in Escherichia coli were investigated by cloning the 5' UTR and the signal peptide sequence separately. Cells transformed with the plasmid containing both the first 30 amino acids of the glycoprotein and the 5' UTR showed a severe growth inhibition whereas transformants harboring either the plasmid with the signal sequence or the 5'UTR alone did not show any ingibition. An E. coli promoter-like sequence was found in the 5'UTR and tis promoter acivity was confirmed with a promoter-less GUS gene cloned downstream of the 5'UTR. In the cloning of the Tomato spotted wilt virus (TSWV) glycoprotein G2G1 open reading frame all the recovered plasmids contained stop codons in the signal sequence region. However, clones containing no stop codon were recovered when the signal sequence and the 5'UTR were cloned separately.

• 미생물학회지
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• 제24권3호
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• pp.236-242
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• 1986

The nucleotide sequence of the genetic control site of Bacillus subtilis gene for $(1-4)-{\beta}-D-glucan$ endoglucanase (cellulase) was determined according to the procedures of the dideoxy chain termination method(Sanger et. al., 1977). The deduced amino acid sequence of this enzyme has a hydrophobic signal peptide at the $NH_2$ terminus similar to those found in fifteen other extracellualr enzymes from Bacillus species. This is followed by a sequence resembling the Bacillus ribosome binding site 14 nucleotide before the first codon of the gene. The presumptive promoter sequence was located 92 base pairs upstream fromthe initiation codon. The homology region in signal sequences was striking when comparing all the signal sequences of sixteen extracellular enzymes from Bacillus species so far compiled.

• 생명과학회지
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• 제8권1호
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• pp.102-108
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• 1998

Gltcosylphosphatidylinositol (GPI)에 의해 고정된 단백질의 초기 형태는 골지체에서의 직접적인 processing을 수행하기 위한 아미노와 카르 복시 말단의 hydrophobic signal sequence를 소유하고 있다. 앞서, mouse 임파구로부터 NAD;arginine ADP-ribosyltransferase (Yac-1)가 클로닝되었으며 Yac-1 transferase의 아미노산 배열을 추정해 본 결과, hydrophobic 아미노와 카르복시 말단을 포함하고 있었으며 이는 GPI-anchroed 단백질들의 알려진 signal sequence와 일치하였다. 미 transferase는 야생형의 cDNA로 transfection된 NMU (rat mammary adenocarcinoma) cell의 표면에 존재하였으며 phosphoatidylinosotol-specific phospholipase C에 의해 방출되어졌다. 카르복시 말단의 hydrophobic sequence가 없는 돌연변이체는 수용성이며 분비성인 transferase를 생산하였다. 이러한 사실은 카르복시 말단의 sequence가 없는 돌연변이체는 수용성이며 분비성인 transferase를 생산하였다. 이러한 사실은 카르복시 말단의 sequence가 GPI의 부착에 중요함을 나타내준다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권1호
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• pp.52-55
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• 2002

Flow cytometric techniques were used to investigate cell size, protein content and cell cycle behavior of recombinant Saccharomyces cerevisiae strains producing human lysozyme (HLZ). Two different signal sequences, the native yeast $MF\alpha1$ signal sequence and the rat $\alpha-amylase$ signal sequence, were used for secretion of HLZ. The strain containing the rat $\alpha-amylase$ signal sequence showed a higher level of internal lysozyme and lower specific growth rates. Flow cytometric analysis of the total protein content and cell size showed the strain harboring the native yeast signal sequence had a higher total protein content than the strain containing the rat $\alpha-amylase$ signal sequence. Cell cycle analysis indicated that the two lysozyme producing recombinant strains had an increased number of cells in the $G_2+M$ phase of the yeast cell cycle compared with the host strain SEY2102.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제4권2호
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• pp.155-160
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• 2001

목적: H. pylori의 vacA 대립유전자는 종족과 지역에 따라 다양하게 나타나고 있다. 저자들은 H. pylori에 감염된 소아의 위생검조직에서 vacA 대립 유전자에 대한 중합효소연쇄반응과 유전자염기분석을 실시하여 한국의 signal sequence와 mid-region의 다형성 및 고유의 시발체를 연구하고자 하였다. 방법: 상부 위내시경을 시행한 후 H. pylori 감염으로 진단된 10~18세 50명의 환아를 대상으로 위생검조직을 이용하여 vacA 대립유전자에 대한 PCR과 DNA 분석을 실시하였다. 이들 결과와 다른 나라의 vacA 대립유전자를 비교분석하였고 우리나라의 고유한 염기배열을 갖는 시발체를 제작하였다. 결과: 1) 서구의 시발체를 사용한 50명 중 30명(60%)에서 모두 s1이 검출되었고 이중 s1a가 14명, s1c 15명, s1a/s1c hybrid가 한 명이었으며 s1b는 발견되지 않았다. s1c/m1이 가장 많은 형이었다. 2) 우리 나라에 공통으로 발견되는 염기변이가 s1a에서는 GGGAGCGTTR, s1c는 GGGGYTATTG 이었으며 이들을 이용하여 새로운 시발체를 고안하였다(VASK-F, VASK-R, S1AK-F, S1CK-F). 새로이 제작된 시발체로 처음의 50개 조직을 재검한 결과 50개 모두에서 s region이 양성이었다. 결론: 우리 나라의 주된 vacA 대립유전자형조합은 s1c/m1이었고, vacA signal sequence의 한국 고유의 시발체를 만들었음을 보고하는 바이다.

• BMB Reports
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• 제39권6호
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• pp.717-721
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• 2006

In vitro analyses of type I signal peptidase activities require protein precursors as substrates. Usually, these pre-proteins are expressed in vitro and cleavage of the signal sequence is followed by SDS polyacrylamide gel electrophoresis coupled with autoradiography. Radioactive amino acids have to be incorporated in the expressed protein, since the amount of the in vitro expressed protein is usually very low and processing of the signal peptide cannot be followed by SDS polyacrylamide gel electrophoresis alone. Here we describe a rapid and simple method to express large amounts of a protein precursor in E. coli. We have analyzed the effect of ionophors as well as of azide on the accumulation of expressed protein precursors. Azide blocks the function of SecA and the ionophors dissipate the electrochemical gradient across the cytoplasmic membrane of E. coli. Addition of azide ions resulted in the formation of inclusion bodies, highly enriched with pre-apo-plastocyanine. Plastocyanine is a soluble copper protein, which can be found in the periplasmic space of cyanobacteria as well as in the thylakoid lumen of cyanobacteria and chloroplasts, and the pre-protein contains a cleavable signal sequence at its N-terminus. After purification of cyanobacterial pre-apo-plastocyanine, its signal sequence can be cleaved off by the E. coli signal peptidase, and protein processing was followed on Coomassie stained SDS polyacrylamide gels. We are optimistic that the presented method can be further developed and applied.

• 대한교통학회지
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• 제14권2호
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• pp.45-58
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• 1996

In a large signal intersection, it is the most important to set phase sequences and phase intervals of traffic signal in order to improve the efficiency of the capacity as well as safety. These setting allows to select the best sequence of signal phase among several alternatives, and thus to rearrange the starting and ending points of the individual phase using an effective interphase periods (EIP). The EIP is a gap between previous and current traffic movements at a potential collision point in an intersection. Each of traffic movements has an equality for safety and efficiency at the balanced condition of EIP. This paper presents how to set optimally the phase sequences and intervals of traffic signal in an intersection using phase based approach. And in the second part, we applied the theory developed in the first part. In particular, a numerical example of phase base signal setting is presented using a matrix computation method in order to select the best sequence among several alternatives, and thus to rearrange the starting and ending points of the individual phase using the EIP. This method also allows to apply to optimum signal setting even in five-lag or staggered-type intersection.