• Journal of Microbiology and Biotechnology
• /
• 제15권4호
• /
• pp.844-854
• /
• 2005

We constructed a defined physical and genetic map of H. pylori strain 51, previously isolated from a Korean patient with a duodenal ulcer, by combining a restriction analysis by pulse-field gel electrophoresis with the construction of a BAC library. A Notl-digest of H. pylori strain 51 genome yielded seven fragments, from which the genomic size was estimated to be 1,698$\pm$24 kb. The BAC library was constructed from 50 to 200 kb fragments of HindIII-digested genomic DNA. From 700 BAC clones, an ordered overlapping maxi-set of 82 BAC clones was assembled that covered the entire genome. The positions of 15 genes were localized in the strain 51 genome with 4-22 kb of resolution and were compared with their orthologues in strain 26695 and strain J99. The arrangement of the 15 genes was identical in strain 51 and strain J99, except for flaA and hpaA. The plasticity zone of strain 51, like that of strain J99, was located in the single region, and was shorter than those of strain 26695 and strain J99. The strain 51 plasticity zone consisted of ORFs common only to strain 51 and J99 or to strain 51 and 26695, as well as strain 51-specific ORFs. Three genetic translocations and/or inversions were found between orthologue ORFs in strain 51 and strain J99. These results show that the chromosomal organization of strain 51 differs from Western strains such as strain 26695 and strain J99.

• Applied Biological Chemistry
• /
• 제28권1호
• /
• pp.19-27
• /
• 1985

율무와 염주 전분을 분리하여 입자의 형태와 몇가지 물리화학적인 특성을 검토하여 다음과 같은 결과를 얻었다. 1. 광학 현미경으로 본 입자의 외형은 6각형, 8각형, 구형이었고, 평균직경은 율무와 염주 모두 $12.0{\mu}$이었다. 2. X-선 회절에 의한 결정구조는 A-type이었고, amylose함량은 율무전분이 0%, 염주전분은 23%였다. 3. 요오드 친화성은 율무전분이 0.08%, 염주전분은 4.2%이었고, blue value는 각각 0.13과 0.43이었다. 4. 다율무전분의 amylopectin분자의 1 segment 당 D-glucose 평균 중합도는 23이었고, 율무 및 염주전분의 alkali number는 각각 2.4와 7.2였다. 5. 팽화력은 율무와 염주 전분에서 각각 280과 20이었고, 가열에 의한 팽윤 현상은 율무전분이 염주전분보다 2배 높았으나, 융해도는 1/2배로 낮았다. 6. 0.1% 전분농도의 광투과도는 율무와 염주 전분 모두 $60^{\circ}C$에서 증가하는 호화양상을 보였고 amylogram에 의한 호화개시온도는 율무전분이 $68.5^{\circ}C$, 염주전분이 $78^{\circ}C$이었고 최고점도는 920 B.U.와 310 B.U.였으며 율무부분은 set back이 아주 낮았다. 7. 고유점도는 율무와 염주전분에서 각각 1.49, 1.77이었고 점조도지수는 0.67과 0.56이었다. 8. 전분 gel의 노화양상은 율무전분에서는 $2^{\circ}C$에서 거의 일어나지 않았고 염주전분은 완만하게 노화되었다.

• Journal of Microbiology and Biotechnology
• /
• 제28권4호
• /
• pp.588-596
• /
• 2018

An endo-${\beta}$-1,4-glucanase gene, cel9K, was cloned using the shot-gun method from Paenibacillus sp. X4, which was isolated from alpine soil. The gene was 2,994 bp in length, encoding a protein of 997 amino acid residues with a predicted signal peptide composed of 32 amino acid residues. Cel9K was a multimodular enzyme, and the molecular mass and theoretical pI of the mature Cel9K were 103.5 kDa and 4.81, respectively. Cel9K contains the GGxxDAGD, PHHR, GAxxGG, YxDDI, and EVxxDYN motifs found in most glycoside hydrolase family 9 (GH9) members. The protein sequence showed the highest similarity (88%) with the cellulase of Bacillus sp. BP23 in comparison with the enzymes with reported properties. The enzyme was purified by chromatography using HiTrap Q, CHT-II, and HiTrap Butyl HP. Using SDS-PAGE/activity staining, the molecular mass of Cel9K was estimated to be 93 kDa, which is a truncated form produced by the proteolytic cleavage of its C-terminus. Cel9K was optimally active at pH 5.5 and $50^{\circ}C$ and showed a half-life of 59.2 min at $50^{\circ}C$. The CMCase activity was increased to more than 150% in the presence of 2 mM $Na^+$, $K^+$, and $Ba^{2+}$, but decreased significantly to less than 50% by $Mn^{2+}$ and $Co^{2+}$. The addition of Cel9K to a commercial enzyme set (Celluclast 1.5L + Novozym 188) increased the saccharification of the pretreated reed and rice straw powders by 30.4% and 15.9%, respectively. The results suggest that Cel9K can be used to enhance the enzymatic conversion of lignocellulosic biomass to reducing sugars as an additive.

• 한국조경학회지
• /
• 제18권4호
• /
• pp.45-71
• /
• 1991

The landscape systems in Korean island settlements can be recognized as results of ingabitants' ecological adptation to the isolated environment with the limited natural resources. Both the fishery dominant industry in island society and ecological nature of its environments seem to have influenced on inhabitants' environmental cognition as well as the physical landscape of island villages such as its location, spatial pattern in each village, housing form and so on. This study was done mainly by both refering to the related documents and direct observations in case study areas, and results of the study can be summarized as follows. 1. In general, the landscape of an individual island seems to take more innate characteristics of island's own, corresponding to the degree of isolation from mainland. That is, while the landscape of island in neighboring waters takes both inland-like and island-innate landscape character at the same time, the one in the open sea far from land takes more innate landscape character of all island's own in the aspects of village location, land use and housing density etc. 2. The convex landform of most islands brings about more centrifugal village allocation than centripetal allocation in most inland villages. And thus most villages in each island face extremely diverse directions different from the south facing preference in most inland rural villages. 3. Most island villages tend to be located along the ecologically transitional strip between land and sea, so called 'line of life', rather than between hilly slope and flat land as being in most inland village locations. So they are located with marine ecology bounded fishing ground ahead and land ecology bounded agricultural site at the back of them. 4. The settlement pattern of the island fishing villages shows more compact spatial structure than that of inland agricultural villages, due to the absolute limits of usable land resources and the adaptation to the marine environment with severe sea winds and waves or for the easy accessability to the fishing grounds. And also the managerial patterns of public owned sea weed catching ground, which take each family as the unit of usership rather than an individual, seem to make the villagescape more compact and the size of Individual residence smaller than that of inland agricultural village. 5. The folk shrine('Dand') systems, in persrective of villagescape, represent innate environmental cognition of island inhabitants above all other cultural landscape elements in the island. Usually the kinds and the meanings of island's communal shrine and its allocative patternsin island villagescape are composed of set with binary opposition, for example 'Upper shrine(representing 'earth', 'mountain' or 'fire')' and 'Lower Shrine(representing 'sea', 'dragon' or 'water') are those. They are usually located at contrary positions in villagescape each other. That is, they are located at 'the virtical center or visual terminus(Upper shrine at hillside behind the village)' and 'the border or entrance(Lower Shrine at seashore in front of the village)'. Each of these shirines' divinity coincides with each subsystem of island's natural eco-system(earth sphere vs marine sphere) and they also contribute to ecological conservation, bonded with the 'Sacred Forest(usually with another function of windbreak)' or 'Sacred Natural Fountain' nearby them, which are representatives of island's natural resources.

• 한국자원식물학회:학술대회논문집
• /
• 한국자원식물학회 2018년도 추계학술대회
• /
• pp.73-73
• /
• 2018

Bacterial leaf blight(BLB), caused by X. oryzae pv. oryzae(Xoo), is one of the most destructive diseases of rice due to its high epidemic potential. Understanding BLB resistance at a genetic level is important to further improve the rice breeding that provides one of the best approaches to control BLB disease. In the present investigation, a collection of 192 accessions was used in the genome-wide association study (GWAS) for BLB resistance loci against four Korean races of Xoo that were represented by the prevailing BLB isolates under Xoo differential system. A total of 192 accessions of rice germplasm were selected on the basis of the bioassay using four isolated races of Xoo such as K1, K2, K3 and K3a. The selected accessions was used to prepare 384-plex genotyping by sequencing (GBS) libraries and Illumina HiSeq 2000 paired- end read was used for GBS sequencing. GWAS was conducted using T ASSEL 5.0. The T ASSEL program uses a mixed linear model (MLM). T he results of the bioassay using a selected set of 192 accessions showed that a large number of accessions (93.75%) were resistant to K1 race, while the least number of accessions (34.37%) resisted K3a race. For races K2 and K3, the resistant germplasm proportion remained between 66.67 to 70.83%. T he genotypic data produced SNP matrix for a total of 293,379 SNPs. After imputation the missing data was removed, which exhibited 34,724 SNPs for association analysis. GWAS results showed strong signals of association at a threshold of [-log10(P-value)] more than5 (K1 and K2) and more than4 (K3 and K3a) for nine of the 39 SNPs, which are plausible candidate loci of resistance genes. T hese SNP loci were positioned on rice chromosome 2, 9, and 11 for K1 and K2 races, whereas on chromosome 4, 6, 11, and 12 for K3 and K3a races. The significant loci detected have also been illustrated, NBS-LRR type disease resistance protein, SNARE domain containing protein, Histone deacetylase 19, NADP-dependent oxidoreductase, and other expressed and unknown proteins. Our results provide a better understanding of the distribution of genetic variation of BLB resistance to Korean pathogen races and breeding of resistant rice.

• Ocean and Polar Research
• /
• 제35권4호
• /
• pp.407-414
• /
• 2013

One of the most important challenges facing the Spirulina mass cultivation industry is to find a way to reduce the high production costs involved in production. Although the most commercial medium (Zarrouk's medium) for Spirulina cultivation is too expensive to use, it contains higher amount of $NaHCO_3$ (16.80 g $L^{-1}$), trace metals and vitamin solutions. The purpose of this study was to increase the efficiency of Spirulina platensis biomass production by developing a low-cost culture medium at an isolated tropical island such as Chuuk State, Federated States of Micronesia (FSM). This study set out to formulate a lowcost medium for the culture of S. platensis, by substituting nutrients of Zarrouk's medium using fertilizer- grade urea and soil extract with a different concentration of carbon source under natural weather condition. In order to select a low-cost culture medium of S. platensis, 10 culture media were prepared with different concentrations of nitrogen (urea and $NaNO_3$) and $NaHCO_3$. The highest maximum specific growth rate (${\mu}max$) and mass production were 0.50 $day^{-1}$ and 1.05 g $L^{-1}$ in modified medium ($NaHCO_3$ 7.50 g $L^{-1}$, urea 2.00 g $L^{-1}$ without $NaNO_3$) among all the synthesized media. Protein (56.14%) and carbohydrate (16.21%) concentrations of the lyophilized standard samples were estimated with highest concentration of glutamic acid (14.93%). This study revealed that the use of a low concentration of urea and $NaHCO_3$ with soil extract was an affordable medium for natural mass cultivation in the FSM.

• 식물병연구
• /
• 제22권4호
• /
• pp.269-275
• /
• 2016

E. pyrifoliae에 의한 과수 가지검은마름병은 국내에서 1995년 최초 발생이래 2016년까지 꾸준히 발생하여 과수농가에 피해를 주고 있는 세균병해이다. 가지검은마름병 발생 농가의 폐원조치 및 공적방제로 인한 경제적 피해 감소를 위하여, 병징이 관찰되는 이병조직 및 건전조직 내의 병원 세균을 검출하여 효율적 관리방안을 마련하고자 본 연구를 수행하였다. 가지검은마름병원세균의 검출은 genomic DNA 추출과정을 생략한 순수 균총만을 이용하는 colony-PCR을 이용하였으며, 이를 위해 ERIC 지역에서 제작된 가지검은마름병원세균 특이 프라이머 EpSPF/EpSPR 프라이머쌍을 선발하였다. 특이 프라이머를 활용한 colony-PCR 방법으로 2014-2015년 4-10월까지 사과나무 생육기간 동안 가지검은마름병 발생상황을 모니터링한 결과, $25^{\circ}C$ 일 평균 온도 기간인 5월 중순부터 7월 초순까지 발병이 가장 빈번하였다. 발병가지 내 병원세균의 존재유무 검정 결과 병징 부위와 이로부터 20 cm 내 건전조직에서만 병원세균이 지속적으로 검출되었다. 따라서 이미 발생한 가지검은마름병을 효율적으로 관리하기 위해 이병조직과 건전조직 경계 부위로부터 20 cm 이상에서 가지치기를 하는 것이 매우 적절할 것으로 판단된다.

• 생명과학회지
• /
• 제17권8호통권88호
• /
• pp.1157-1165
• /
• 2007

포도 ASR (VvMSA) 단백질은 hexose transporter 유전자 VvHT1의 전사를 조절하는 조절 인자 중의 하나로서 sugar 및 abscisic acid (ABA) 신호에 의해 발현이 유도된다. 본 연구진은 ACP RT-PCR (annealing control primer reverse transcriptase-polymerase chain reaction) 방법을 이용하여 포도 과실발달 과정에서 조절되는 유전자 중 VvMSA와 동일한 cDNA (VlASR)를 클로닝하였다. 이 유전자는 착과 시기에 발현되기 시작하여 과실이 발달하면서 점점 증가하여 착과 후 10 주에 가장 많이 발현되며, 숙기 후반에는 도리어 발현양이 감소하였다. 포도 asr 유전자의 조절기작을 밝히기 위해, 이 유전자의 genomic clone을 분리하였다. 총 1375 bp로 이루어진 이 유전자 절편에는 open reading frame과 100 bp의 intron을 포함하고 있다. 약 600 bp 길이의 프로모터 내에는 sugar 신호전달과 연관이 있는 것으로 알려진 sugar box(sucrose box 3 +sucrose response box 1)가 있다. 프로모터 절편을 reporter 유전자와 연결하여 Arabidopsis에 도입하고 형질전환체를 분석한 결과, reporter 유전자는 sucrose 처리와 상관없이 항상 발현되었다. 이러한 결과는 포도에서 보고된 ASR/VvHT1를 매개로 하는 sugar/ABA 신호전달계가 asr 유전자가 없는 Arabidopsis에서는 작동되지 않음을 시사하고 있다.

• 한국토양비료학회지
• /
• 제37권4호
• /
• pp.266-287
• /
• 2004

식물체에 해를 끼치지 않고 식물체와 공생하는 박테리아는 식물의 생장을 촉진 시키며 친환경적 식물 보호제 역할을 함으로서 높은 관심을 받아왔다. Methylobacterium spp.로 분리된 분홍색 색소를 형성하는 methylotrophic bacteria (PPFMS)는 식물의 잎 표면에 서식한다. 거의 모든 식물체의 잎에는 PPFMS를 가지고있으며, Methylobacterium의 특별한 특성을 가진 이들은 탄소와 에너지원으로 잎의 methanol를 이용한다. 비록 이들 박테리아들은 잘 알려 지지 않았지만. 그들은 식물 대사 작용에 영향을 주면서 함께 진화되어 왔다. 이 주장은 다음의 예로 보인 관찰로서 뒷받침 한다. (1) PPFMS는 씨 안에서 발견되고 (2) PPFMS는 자주 무균 세포 배양에서 발견되고 (3) 적은 수의 PPFMS를 지닌 종자는 낮은 발아율을 보였고, (4) 감소된 PPFMS를 가진 식물들은 낮은 줄기/뿌리 비율을 보이고, (5) 콩깍지 형성 시기에 콩잎에 PPFMS의 엽면처리는 종자 수와 생산량을 높이며, (6) 우산이끼를 배양하는데 있어서 PPFM에 의해 생성된 비타민 Rl2는 우산이끼의 생장을 위해 필요하고 (7) 벼에 있어서 Rhizoctonia solani에 인해 나타나는 엽초마름병의 발병률은 PPFMS를 처리한 벼에서 억제되거나 감소되었고, 그리고 (8) PPFM의 종은 기공과 엽록소의 농도, malic acid의 함량을 증가시켜 식물의 광합성 능을 증가시켰다. Methylobacterium spp.은 식물체의 잔사를 이용하거나 식물체에 유용한 대사산물을 생산함으로써 식물의 신진대사에 관여하는 것으로 알려진 공생자이다. 박테리아와 식물체간의 이로운 상호작용에 관해 알려진 많은 보고서들이 있다. 식물체의 수분장애 완화, 광합성호르몬 생산, 그리고 질소고정과 같은 식물의 생장을 촉진시키는 박테리아 종과 같은 선발은 성공적으로 분리 해낼 수 있었고, 작물생산에 있어서 이 같은 미생물의 처리는 생산력을 증가시킬 것이다.

• Journal of Gastric Cancer
• /
• 제16권4호
• /
• pp.221-229
• /
• 2016

Purpose: Dysregulated microRNAs (miRNAs) can contribute to cancer development by leading to abnormal proliferation of cells, apoptosis, and differentiation. Although several miRNAs that are related to gastric cancer have been identified, the reported results have been inconsistent. The aim of this study was to determine miRNA expression profiles and validate miRNAs up- and down-regulated in gastric cancer. Materials and Methods: We evaluated 34 primary gastric cancer tissues and paired adjacent nontumorous gastric tissues. Total RNA was extracted, and low-molecular-weight RNAs (<200 nucleotides) were isolated for further analysis. Two pairs of tissues were processed for GeneChip microarray analysis, and the identified up- and down-regulated miRNAs were validated by real-time quantitative polymerase chain reaction (qPCR). Results: In the set of differentially expressed miRNAs, 5 were overexpressed by more than 2 fold, and 5 were reduced by 2 fold or less in gastric cancer tissues compared with normal gastric tissues. Four of these miRNAs (miR-196b-5p, miR-375, miR-483-5p, and miR-486-5p) were then validated by qPCR, and the relative expression levels of 2 miRNAs (miR-196b-5p and miR-375) were significantly different between cancer and normal tissues. Conclusions: Our results revealed that the expression of miR-196b-5p and miR-375 significantly correlates with gastric cancer. These miRNAs could therefore serve as diagnostic biomarkers of gastric cancer.