• Journal of Microbiology
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• 제44권5호
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• pp.530-536
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• 2006

Bacteriophage P4, a satellite phage of coliphage P2, is a very useful experimental tool for the study of viral capsid assembly and cos-cleavage. For an in vitro cos-cleavage reaction study of the P2-P4 system, new shortened and selectable markers containing P4 derivative plasm ids were designed as a substrate molecules. They were constructed by swapping the non-essential segment of P4 DNA for either the kanamycin resistance (kmr) gene or the ampicillin resistance (apr) gene. The size of the genomes of the resulting markers were 82% (P4 ash8 delRI:: kmr) and 79% (P4 ash8 delRI:: apr) of the wild type P4 genome. To determine the lower limit of genome size that could be packaged into the small P4-size bead, these shortened P4 plasmids were converted to phage particles with infection of the helper phage P2. The conversion of plasmid P4 derivatives to bacteriophage particles was verified by the heat stability test and the burst size determination experiment. CsCl buoyant equilibrium density gradient experiments confirmed not only the genome size of the viable phage form of shortened P4 derivatives, but also their packaging into the small P4-size head. P4 ash8 delRI:: apr turned out to be the smallest P4 genome that can be packaged into P4-sized head.

• 미생물학회지
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• 제39권4호
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• pp.277-282
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• 2003

P2의 sir 변이를 억제하는 변이체 박테리오파아지 P4를 얻기 위하여, P4 ash8 sid71 kmr intS를 박테리오파아지 P2 sir3 용원소에 plating하여 플라크를 형성하는 P4 ost2를 분리하였다. P4 ost2는 1단계 생장실험에서 P2의 sir 변이를 억제하는 P4 변이체로 나타났다. 제한효소 절단 반응으로 유전체 DNA의 재배열이 일어난 단편을 찾아 cloning과 sequencing을 거쳐 P4 ost2의 구조를 규명하였다. P4 ost2의 DNA는, 6.9 kb의 결실을 가진 P4 ash8 sid71 kmr intS의 불완전한 trimer로 2개의 cos-cleavage 부위를 가지는 28.8 kb의 유전체로 밝혀졌다. CsCl 부양균등밀도 편차실험으로 P4 ost2의 DNA 크기를 확인하였고 파아지 머리 안에 packaging된 DNA에 대한 기초적인 구조를 파악하였다. P4 ost2의 분리 동정을 통해, P4 유전체 상의 cos-cleavage 부위의 개수가 Sir-type 파아지 머리의 packaging 반응과는 관련이 없다고 추정할 수 있었다.

• Molecules and Cells
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• 제28권1호
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• pp.25-30
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• 2009

${\beta}$-Arrestins turn off G protein-mediated signals and initiate distinct G protein-independent signaling pathways. We previously demonstrated that angiotensin $AT_1$ receptorbound ${\beta}$-arrestin 1 is cleaved after $Phe^{388}$ upon angiotensin II stimulation. The mechanism and signaling pathway of angiotensin II-induced ${\beta}$-arrestin cleavage remain largely unknown. Here, we show that protein Tyr phosphatase activity is involved in the regulation of ${\beta}$-arrestin 1 cleavage. Tagging of green fluorescent protein (GFP) either to the N-terminus or C-terminus of ${\beta}$-arrestin 1 induced conformational changes and the cleavage of ${\beta}$-arrestin 1 without angiotensin $AT_1$ receptor activation. Orthovanadate and molybdate, inhibitors of protein Tyr phosphatase, attenuated the cleavage of C-terminal GFP-tagged ${\beta}$-arrestin 1 in vitro. The inhibitory effects of okadaic acid and pyrophosphate, which are inhibitors of protein Ser/Thr phosphatase, were less than those of protein Tyr phosphatase inhibitors. Cell-permeable pervanadate inhibited angiotensin II-induced cleavage of ${\beta}$-arrestin 1 in COS-1 cells. Our findings suggest that Tyr phosphorylation signaling is involved in the regulation of angiotensin II-induced ${\beta}$-arrestin cleavage.

• Journal of Microbiology and Biotechnology
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• 제20권7호
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• pp.1114-1120
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• 2010

A chitosan-degrading fungus, BSF114, was isolated from soil. The culture preparation showed strong chitosanolytic enzyme activity at an optimum pH of 4.0 and optimum temperature of $60^{\circ}C$ after 36-40 h fermentation. The rapid decrease in the viscosity of the chitosan solution early in the reaction suggested an endo-type cleavage of the polymeric chitosan chains. To identify the isolated fungus, molecular biological and morphological methods were used. The fungal internal transcribed spacer (ITS) region 1 was amplified, sequenced, and then compared with related sequences in the GenBank database using BLAST. The phylogenetic relationships were then analyzed, and the results showed that the fungus belongs to Aspergillus fumigatus. Morphological observations were also used to confirm the above conclusion. The chitooligosaccharides (COS) obtained through hydrolyzing the colloidal chitosan showed that A. fumigatus BSF114 is suitable for degrading chitosan and producing chitooligosaccharides on a large scale. High concentrations of the COS (1,000 and 500 ${\mu}g/ml$) significantly proliferated mice marrow cells.

• 암석학회지
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• 제26권3호
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• pp.297-309
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• 2017

거창지역의 쥬라기 화강암에 대하여 결의 특성에 대한 분석을 실시하였다. 박편의 확대사진 및 간격-누적빈도 도표에서 도출한 16개 파라미터의 결합을 통하여 결에 대한 종합적인 평가를 실시하였다. 결에 대한 이들 간격의 파라미터의 대표값에 대한 분석 결과를 요약하면 다음과 같다. 첫째, 상기 파라미터는 그룹 I(간격의 빈도수(N), 총 간격($1mm{\geq}$), 상수(a), 지수(${\lambda}$), 지수 직선의 기울기(${\theta}$), 선의 길이(oa') 및 삼각비($sin{\theta}$, $tan{\theta}$) 그리고 그룹 II(평균 간격(Sm), 평균 간격과 중앙 간격 사이의 차이값(Sm-Sme), 밀도(${\rho}$), 선의 길이(oa 및 aa'), 직각삼각형(${\Delta}oaa^{\prime}$)의 면적 및 삼각비($cos{\theta}$)로 분류할 수 있다. 그룹 I에 속하는 8개 파라미터의 값은 H(3번 결, H1+H2)