• 한국환경보건학회지
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• 제13권1호
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• pp.47-57
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• 1987

Owing to the modification of testing methods of disinfectants or antiseptics, variations of bacteria according to characteristics of regions and resistance changes of bacteria, it is necessary that the bactericidal activities of disinfectants or antiscptics should be reevaluated nowadays. This study was carried out to reevaluate in the vitro bactericidal activity of Chlorhexidine gluconate solution. The results of experiment were summarized as follows. 1. For Chlorhexidine gluconate solution, minimal inhibitory concentrations of total bacteria taken from sewage water and Legionella bozemanii were $2.0\times 10^{-3}$%, $1.0\times 10^{-2}$%, respectively and were comparatively high. Minimal inhibitory concentration of Shigella flexneri was $1.6\times 10^{-4}$%, and was comparatively low. 2. For total bacteria taken from sewage water, it was killed within 15 minute in 0.1% Chlorhexidine gluconate solution when number of cells was $1.6\times 10^7$/ml. 3. For 0.0125% Chlorhexidine gluconate solution, decimal reduction times of Ps. aeruginosa, S. typhi, E. Coli were 45 sec, 25 sec, 18 sec repectively. For 1%, 0.125% Chlorhexidine gluconate solution, decimal reduction times of Legionella bozemanii were 10 sec, 45 sec respectively. 4. There was significant difference in the bactericidal activity of Chlorhexidine gluconate solution according to temperattire. Phenol coefficient of Chlorhexidine gluconate solution as using Staph. aureus was 100 and comparatively higher than that of other disinfectants. In comparison with other disinfectants, Legionella bozemanii was killed within 5 minutes in 0.02% KMnO$_4$ and 0.125% Chlorhexidine giuconate solution but was not killed within 3 minutes in 1% 0-cresol, 1% Phenol.

• Genomics & Informatics
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• 제12권4호
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• pp.268-275
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• 2014

The harshness of legionellosis differs from mild Pontiac fever to potentially fatal Legionnaire's disease. The increasing development of drug resistance against legionellosis has led to explore new novel drug targets. It has been found that phosphoglucosamine mutase, phosphomannomutase, and phosphoglyceromutase enzymes can be used as the most probable therapeutic drug targets through extensive data mining. Phosphoglucosamine mutase is involved in amino sugar and nucleotide sugar metabolism. The purpose of this study was to predict the potential target of that specific drug. For this, the 3D structure of phosphoglucosamine mutase of Legionella pneumophila (strain Paris) was determined by means of homology modeling through Phyre2 and refined by ModRefiner. Then, the designed model was evaluated with a structure validation program, for instance, PROCHECK, ERRAT, Verify3D, and QMEAN, for further structural analysis. Secondary structural features were determined through self-optimized prediction method with alignment (SOPMA) and interacting networks by STRING. Consequently, we performed molecular docking studies. The analytical result of PROCHECK showed that 95.0% of the residues are in the most favored region, 4.50% are in the additional allowed region and 0.50% are in the generously allowed region of the Ramachandran plot. Verify3D graph value indicates a score of 0.71 and 89.791, 1.11 for ERRAT and QMEAN respectively. Arg419, Thr414, Ser412, and Thr9 were found to dock the substrate for the most favorable binding of S-mercaptocysteine. However, these findings from this current study will pave the way for further extensive investigation of this enzyme in wet lab experiments and in that way assist drug design against legionellosis.

• 생명과학회지
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• 제11권5호
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• pp.483-488
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• 2001

최근 다양한 분야에서 생물학적 제제개발에 관한 연구가 활발한다. 본 연구에서는 생물학적 제제개발을 위한 일련의 연구로 Pseudomonas aeruginosa KLP-2가 생산하는 항균성 물질을 동정하고, 생리화학적 특성을 확인하였다. 본 항균성 물질을 전제하여 FAB-MS로 확인한 결과 pyocyanine으로 동정되었으며, 진청색의 needles 성상을 나타내었고 chloroform, methanol, ethyl acetate와 같은 용매에 높은 용해도를 나타내었다. Pyocyanine의 UV spectrum은 methanol에서 최대 흡광치(318 nm)를 보였고, FAB-MS로 확인한 결과 m/z 211에서 protonated molecular ion(M+H)$^{+}$ 이 관찰되었으며, 분자식은 $C_{13}$H$_{10}$ N$_{2}$O로 확인되었다. Pyocyanine 은 Bacillus cereus, Bacillus subtilis, Micrococcus luteus, Rodococcus equi, Staphylococcus aureus, Streptococcus faecalis, E. coli. Kegionella peneumophila, Shigella flexneri, Shigela boydii, Shigella sonnei, NAG Vibro cholerae, Vibrio parahaemolyticus, Vibro vulnificus, Yersinia enterocolitica 및 Saccharomyces cerevisiae 등의 다양한 세균에 대하여 항균활성을 보여 비교적 넓은 항균범위를 나타내었으며, 특히 Legionella pneumophila에 대하여 0.5$\mu$g의 pyocyanine을 함유한 disk가 48mm의 억제환을 타나내어 가장 높은 항균활성을 보였다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 2003년도 한국생물과학협회 학술발표대회
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• pp.131.2-131
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• 2003

No Abstract, See Full Text

• Clinical and Experimental Pediatrics
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• 제63권12호
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• pp.469-476
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• 2020

The major pathogens that cause atypical pneumonia are Mycoplasma pneumoniae, Chlamydophila pneumoniae, and Legionella pneumophila. Community-acquired pneumonia (CAP) caused by M. pneumoniae or C. pneumoniae is common in children and presents as a relatively mild and self-limiting disease. CAP due to L. pneumophila is very rare in children and progresses rapidly, with fatal outcomes if not treated early. M. pneumoniae, C. pneumoniae, and L. pneumophila have no cell walls; therefore, they do not respond to β-lactam antibiotics. Accordingly, macrolides, tetracyclines, and fluoroquinolones are the treatments of choice for atypical pneumonia. Macrolides are the first-line antibiotics used in children because of their low minimum inhibitory concentrations and high safety. The incidence of pneumonia caused by macrolide-resistant M. pneumoniae that harbors point mutations has been increasing since 2000, particularly in Korea, Japan, and China. The marked increase in macrolide-resistant M. pneumoniae pneumonia (MRMP) is partly attributed to the excessive use of macrolides. MRMP does not always lead to clinical nonresponsiveness to macrolides. Furthermore, severe complicated MRMP responds to corticosteroids without requiring a change in antibiotic. This implies that the hyper-inflammatory status of the host can induce clinically refractory pneumonia regardless of mutation. Empirical macrolide therapy in children with mild to moderate CAP, particularly during periods without M. pneumoniae epidemics, may not provide additional benefits over β-lactam monotherapy and can increase the risk of MRMP.

• Journal of Microbiology and Biotechnology
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• 제12권1호
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• pp.114-120
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• 2002

A 1,989-bp genomic region encoding nickel resistance genes was isolated from Legionella pneumophila, a pathogen for legionellosis. From a sequencing and computer analysis, the region was found to harbor two structural genes, a nreB-like protein gene (1,149 bp) and a nreA-like protein gene (270 bp), in a row. Both genes exhibited a significant degree of similarity to the corresponding genes from Synechocystis sp. PCC6803 ($54\%$ amino acid sequence identity) and Achromobacter xylosoxidans 31A ($76\%$). The gene was successfully expressed in E. coli MG1655 and conferred a nickel resistance of up to 5 mM in an LB medium and 3 mM in a TMS medium including gluconate as the sole carbon source. E. coli harboring the nickel resistance gene also exhibited a substantial resistance to cobalt, yet no resistance to cadmium or zinc. Since the extracellular concentration of nickel remained constant during the whole period of cultivation, it was confirmed that the nickel resistance was provided by an efflux system like the $Ni^2＋$permease (nrsD) of Synechocystis sp. strain PCC6803. Since polyphosphate (poly-P) is known as a global regulator for gene expression as well as a potential virulence factor in E. coli, the nickel resistance of a ppk mutant of E. coli MG 1655 harboring the nickel resistance gene from L. pneumophila was compared with that of its parental strain. The nickel resistance was significantly attenuated by ppk inactivation, which was more pronounced in an LB medium than in a TMS medium.

• 생명과학회지
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• 제15권2호
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• pp.161-168
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• 2005

2001년부터 2003년까지 부산지역의 냉각탑수에서 분리한 L. pneumophila (serogroup 1) 39균주에 대해 제한효소 SfiI 처리한 경우 PFGE 양상은 dice coefficient $<65\%$의 유사성을 가진 band를 Awl로 10개의 pulsotype으로 나누었고, 가장 많았던 유형은 E pulsotype으로 39주중 18주로 $46.2\%$를 나타내었으며, 그 외 A pulsotype $17.9\%$, C pulsotype $15.4\%$, F pulsotype $7.7\%$ 및 B, D, G, H, I, J pulsotype이 각각 $2.6\%$로 유전적 양상이 다양하였다. 제한효소 NotI 처리한 경우 PFGE 양상은 dice coefficient $<60\%$의 유사성을 가진 band를 $a\~h$로 8개의 pulsotype으로 나누었고, 가장 많았던 유형은 f pulsotype이 $38.5\%$였으며 그 외 d pulsotype $20.5\%$, e pulsotype $17.9\%$, a pulsotype $10.3\%$, h pulsotype $7.7\%$ 및 b, c, g pulsotype이 각각 $2.6\%$를 차지하였다. 본 연구를 통하여 부산지역에서 분리되는 레지오넬라균에 대한 유전자 유형분석 결과를 데이터베이스화하여, 레지오넬라증의 집단 발생 또는 산발적인 질병 발생이 있을 경우 분자학적 측면에서 사람과 환경에서 분리된 균으로부터 감염원과 감염경로를 규명하는 역학적인 도구로써 이용 가능할 것으로 사료되었다.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2007년도 춘계 학술발표회 발표논문집
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• pp.346-350
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• 2007

Pt/TI, Ir/Ti, Ru/Ti의 세가지 종류의 전극을 이용하여 전기분해공정에서 레지오넬라균의소독효과를 고찰한 결과 기존 산업계에서 가장 많이 사용하는 Pt/Ti 전극의 성능이 떨어지는 것으로 나타났고, Ru/Ti 전극의 성능이 가장 우수한 것으로 나타났다. NaCl 농도가 높을수록 전기전도도가 높아지기 때문에 소요되는 전력도 감소하고 소독효과도 증가하지만 염소에 대한 냉각수의 수질기준을 고려할 때 최적 NaCl 첨가량은 0.0125%로 사료되었다. 전극 간격이 넓을수록 소독효과가 감소하는 것으로 나타났다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 한국생물과학협회 학술발표대회
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• pp.229.2-229
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• 1999

No Abstract, See Full Text

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.206-207
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• 2000

스크린프린팅 된 탄소전극과 항체가 결합된 리포좀을 이용한 일회용 전기화학발광 면역센서를 구성하였다. 분석물질농도에 비례하여 분석물질-면역리포좀 복합체는 모세관현상에 의해 membrane strip에서 전극 상으로 전달되었고, 이 리포좀은 계면 활성제에 의해 파괴되고 신호발생에 이용되는 ruthenium이 방출되었다. 이와 같은 면역센서의 성능은 의료현장검사 혹은 자가진단에 적합할 것으로 예측된다.