• 한국해양학회지
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• 제5권2호
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• pp.65-72
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• 1970

지상의 각 하천수계는 적지않은 세균류에 의한 오염을 받고 있어, 이것은 우리의 환경위생 또는 보건위생면에서 큰 관심사가 될 뿐 아니라 이것들은 결국 해역으로 유입되어 이곳에 서식하는 각종 연안수족을 오염하여 우리의 식품위생면에서도 많은 주의를 환기시키고 있다. 환경수의 세균오염에는 여러 가지가 있으나 여기서는 분변성 오염세균에만 한정한다. 환경수에 혼입되는 분변성 오염세균에는 대장균군, 대장균 및 장구균 등이 있으며, 이것은 우리나라의 하천수에도 적지않은 량이 출현하고 있으며 (최,김 1970) 특히 도시폐수의 주입이 많은 곳에서는 이것들에 의한 오염이 심대할 것이 예상된다. 그러나 이러한 세균들은 담수 및 해수에서 유래되는 것이 아니므로, 담수역에 있어서 또는 해역으로 유입된 후의 동태가 매우 흥미롭다.

• 미생물학회지
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• 제38권4호
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• pp.318-321
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• 2002

토양 등의 인 제한환경에서 특이적으로 발현하는 벡터를 구축하기 위해서 Enterobacter areogenes의 phoA 유전자의 promoter가 든 pEAAP를 구축하였다. pEAAP는 pET-22b(+)을 BglII와 XbaI으로 절단하여 T7 promoter와 lac operator를 제거하고pho box가 포함된 phoA promoter를 삽입하여 구축하였다. pEAAP가 인 제한 환경에서 특이적으로 발현되는지 조사하고자 Bacillus subtillis var. amyloliquefaciens (KCTC 8913P)의 Phytase유전자인 Bsa-phy1을 도입한 pEAPHY1을 구축하였다. CK-PHY1 (pEAPHY1을 도입한Escherichia coli JM109)는 인 제한 환경에서 41 kD)의 Bsa-Phy1을 발현하였다. 또한, CK-PHY1은 phytate를 유일한 인산원으로 첨가된 고체배지에서 phytate를 분해하여 투명대를 형성하였다.

• 대한임상검사과학회지
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• 제39권3호
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• pp.178-182
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• 2007

During 2006, the antibiotic resistance rate were investigated in gram negative bacteria. Resistance to piperacillin were detected at 60% in Escherichia coli, and 37% in Klebsiella pneumoniae. Ceftriaxone were detected 58% in Enterobacter cloacae, 52% in Acinetobacter baumannii, 43% in Enterobacter aerogenes and 76% were detected in Serratia marcescens. Between 1998 and 2007 antibiotic resistance rate were decreased in seven types antibiotic drugs. but, ceftazidime were increased from 12 to 20% during this times. In addition, E. coli, E. cloacae, A. baumannii and E. aerogenes were more isolated from May to June and K. pneumoniae and S. marcescens were more isolated from July to September. We should monitor and control antibiotic use and regularly survey antibiotic resistance patterns among pathogens in the hospital.

• 농업과학연구
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• 제43권3호
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• pp.401-414
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• 2016

The synergistic effect on phosphate solubilization of single- and co-inoculation of two phosphate solubilizing bacteria, Burkholderia anthina PSB-15 and Enterobacter aerogenes PSB-16, was assessed in liquid medium and green gram plants. Co-inoculation of two strains was found to release the highest content of soluble phosphorus ($519{\mu}g\;mL^{-1}$) into the medium, followed by single inoculation of Burkholderia strain ($492{\mu}g\;mL^{-1}$) and Enterobacter strain ($483{\mu}g\;mL^{-1}$). However, there was no significant difference between single inoculation of bacterial strain and co-inoculation of two bacterial strains in terms of phosphorous release. The highest pH reduction, organic acid production, and glucose consumption were observed in the culture medium co-inoculated with PSB-15 and PSB-16 strains rather than that of single inoculation. Based on the plant growth promotion bioassay, co-inoculated mung bean seedlings recorded 9% and 8% higher shoot and root growth, respectively, compared to the control. Therefore, in conclusion, co-inoculation of the strains B. anthina and E. aerogenes displayed better performance in stimulating plant growth than inoculation of each strain alone. However, considering the short assessment period of the present study, we recommend engaging in further work under field conditions in order to test the suitability of these strains as bio-inoculants.

• 한국약용작물학회지
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• 제16권2호
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• pp.112-117
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• 2008

사철쑥의 수확시기와 부위에 따른 항산화성을 조사한 결과 총 페놀과 프라보노이드 함량은 잎>종실>줄기 순으로 낮아졌다. 6월 30일 잎에는 78.8 mg/g DW의 페놀과 78.2 mg/g DW의 플라보노이드가 함유되어 있었다. DDPH에 의한 radical소거능이 50%로 감소되는 시료 농도인 $RC_{50}$이 6월 30일 잎에서 $5.42\;{\mu}g$으로 낮게 나타나 항산화성이 가장 높았다. 이 때 BHA, BHT와 ${\alpha}-tocopherol$의 $RC_{50}$은 각각 $3.09\;{\mu}g,\;24.30\;{\mu}g\;and\;2.87\;{\mu}g$이었다. 또한 종실에서 Bacillus subtilis, Staphylococcus aureus, Enterobacter aerogenes, Citrobacter freundii, Vibrio vulnificus, Pseudomonas aeruginosa, Saccharomyces cerevisiae 등 7종에 대해 항균성이 나타난 반면 잎과 줄기에서는 항균성이 거의 없었다. 수확시기에 따른 종실의 Bacillus subtilis, Staphylococcus aureus, Vibrio vulnificus, Saccharomyces cerevisiae에 대한 향균성은 8월 30일에 높았으며 Enterobacter aerogenes, Citrobacter freundii, Pseudomonas aeruginosa에 대한 항균성은 7월 30일에 높았다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 제2회 추계심포지움
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• pp.69-80
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• 1994

Although ureases play important roles in microbial nitrogen metabolism and in the pathogenesis of several human diseases, little is known of the mechanism of metallocenter biosynthesis in this Ni-Containing enzyme. Klebsiella aerogenes urease apo-protein was purified from cells grown in the absence of Ni. The purified apo-enzyme showed the same native molecular weight, charge, and subunit stoichiometry as the holo-enzyme. Chemical modification studies were consistent with histidinyl ligation of Ni. Apo-enzyme could not be activated by simple addition of Ni ions suggesting a requirement for a cellular factor. Deletion analysis showed that four accessory genes (ureD, ureE, ureF, and ureG) are necessary for the functional incorporation of the urease metallocenter. Whereas the $\Delta$ureD, $\Delta$ureF, and $\Delta$ureG mutants are inactive and their ureases lack Ni, the $\Delta$ureE mutants retain partial activity and their ureases possess corresponding lower levels of Ni. UreE and UreG peptides were identified by SDS-polyacrylamide gel comparisons of mutant and wild type cells and by N-terminal sequencing. UreD and UreF peptides, which are synthesized at ve교 low levels, were identified by using in vitro transcription/translation methods. Cotransformation of E. coli cells with the complementing plasmids confirmed that ureD and ureF gene products act in trans. UreE was purified and characterized. immunogold electron microscopic studies were used to localize UreE to the cytoplasm. Equilibrium dialysis studies of purified UreE with $^{63}$ NiC1$_2$ showed that it binds ～6 Ni in a specific manner with a $K_{d}$ of 9.6 $\pm$1.3 $\mu$M. Results from spectroscopic studies demonstrated that Ni ions are ligated by 5 histidinyl residues and a sixth N or O atom, consistent with participation of the polyhistidine tail at the carboxyl termini of the dimeric UreE in Ni binding. With these results and other known features of the urease-related gene products, a model for urease metallocenter biosynthesis is proposed in which UreE binds Ni and acts as a Ni donor to the urease apo-protein while UreG binds ATP and couples its Hydrolysis to the Ni incorporation process.ouples its Hydrolysis to the Ni incorporation process.s.

• Applied Biological Chemistry
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• 제17권2호
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• pp.117-124
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• 1974

23종(種)의 대표적(代表約)인 세균(細菌)에 대(對)하여 glucosamine 함량(含量)을 측정(測定)하여 당지질(糖脂質)의 분포(分布)를 조사(調査)하고 당지질(糖脂質)의 함량(含量)과 Gram염색(染色)과의 상관관계(相關關係)를 규명(究明)한바 다음과 같은 결과(結果)를 얻었다. 1. Gram음성균(陰性菌) 및 varieable균(菌)은 그 균체(菌體) 당지질중(糖脂質中) glucosamine함량(含量)이 최소(最少) Proteus vulgaris의 $0.04{\mu}g$에서 부터 최고(最高) Aerobacter aerogenes 의 $2.48{\mu}g$의 범위(範圍)로 분포(分布)되여 있었다. Gram positive균(菌) 및 Bacillus속중(屬中)의 Gram양성균(陽性菌)은 전부(全部) $0.02{\mu}g$ 이하(以下)의 함량(含量)을 갖고 있었다. Gram양성(湯性)인 Corynebacterium sepedonicum 및 Staphylococcus aureaus는 특(特)히 glucosamine함량(含量)이 최소(最少)였다. 이들보다 Gram음성균(陰性菌)은 양성균(湯性菌)과 명확(明確)히 구별(區別)할 수 있을만큼 glucosamine함량(含量)이 많았다. 2. Gram염색(染色)은 당지질(糖脂質) 추출전(抽出前)보다 추출후(抽出後)가 염색(染色)이 더 잘되는 경향(傾向)이였다. 3. Aerobacter aerogenes, Bacillus circulans, Pseudomonas fluorescens 및 Salmonella typhirurium의 4균주(菌株)에서 얻은 당지질(糖脂質)의 적외선(赤外線) spectra는 대체(大體)로 같았으며 다 OH-group C-O, C-O-C, $CH_2+CH_3$, amide 결합(結合), 지방산(脂肪酸) ester 결합(結合), ester carbonyl 결합(結合)의 존재(存在)를 확인(確認)하였다.

• 대한미생물학회지
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• 제15권1호
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• pp.19-32
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• 1980

Besides the benefits of antimicrobial agents in the control of various infectious diseases, widespread and prolonged use of particular antimicrobial agents has brought about the increase of drug-resistant strains in a community and the profound changes in the pattern of infectious diseases. In Korea, there are some remote villages where no clinics and drug stores are available and the residents in those areas are assumed to have fewer chances to contact with antimicrobial agents. In the present study, the differences in susceptibilities to 14 antimicrobial agents between the isolates from rural areas(R) and Seoul National University Hospital(SNUH, H) were studied. The isolates and their numbers were Staphylococcus aureus, R;55, H;68), Enterococci(R;28, H;30), Escherichia coli(R;40, H;40), Enterobacter aerogenes(R;25, H;21) and Klebsiella pneunoniae(R;58, H;67). Minimal inhibitory concentrations(MIC's) of penicillin, ampicillin, carbenicillin, cephalexin, tetracycline, oxytetracyline, doxycycline, minocycline, gentamicin, kanamycin, streptomycin, erythromycin, troleandomycin and co-trimoxazole were determined by agar dilution method. I. Comparison of MIC's and resistant strain proportions between isolates from SNUH and rural areas. MIC's and/or resistant strain proportions of the isolates from SNUH were significantly higher than those of the isolates from rural areas in the cases of 1. S. aureus to doxycycline, streptomycin and kanamycin. 2. E. coli to penicillin, ampicillin, carbenicillin, tetracycline, oxytetracycline, doxycycline, minocycline, streptomycin, kanamycin, erythromycin and co-trimoxazole. 3. E. aerogences to carbenicillin, tetracycline, oxytetracycline, doxycycline, minocycline, streptomycin, kanamycin, genaamicin and co-trimoxazole. 4. K pneunoniae to penicillin, ampicillin, tetracycline, oxytetracycline, doxycycline, monocycline, streptomycin, kanamycine, gentamicin and co-trimoxazole. However, the mean MIC and resistant strain proportion of S. aureus to tetracycline were higher in isolates from rural areas than in those from SNUH and Enterococci showed no differences in susceptibilities to the antimicrobial agents between isolates from rural areas and from SNUH. Therefore, in general, differenes in susceptibility to these antimicrobial agents between the isolates from rural areas and SNUH were remarkably greater and broader in gram negative enteric bacteria. II. Multiple drug resistance pattern. Patterns and incidences of multiple drug resistance were studied with penicillin, ampicillin, tetracycline, cephalexin, gentamicin, streptomcin, kanamycin and co-trimoxazole in Enterococci, E. coli, E. aeroges and K. pneumoniae. There appeared significant differences in the incidence of multiply drug-resistant strains and multiple drug resistance patterns between the isolates from SNUH and rural areas in Enterococci, E. coli, E. aerogenes and K. pneumoniae. However, there was no difference in the incidence of multiply drug-resistant strains between isolates of S. aureus from SNUH and rural areas but the pattern of multiple resistance of the SNUH strains of S. aureus was diverse, while that of the rural strains was predominantly confined to penicillin-tetracycline combination. The incidence of multigly drug-resistant strains and diversity of their patterns were the highest in E. coli strains isolated from SNUH and there were no multiply drug resistant strrains in Enterococci and K. pneumoniae strains isolated from rural areas. The number of drug-resistance determinants was also different between the isolates from rural areas and SNUH. Most of the multiply drug-resistant strains of E. coli, E. aerogenes and K. pneumoniae isolated from SNUH were resistant to more than 3 kinds of antimicrobial agents, most frequently to ampicillin, tetracycline and streptomycin, while multiply drug-resistant strains from rural areas were resistant to 2 kinds of antimicrobial agents among ampicillin, tetracycline and streptomycin. With drug-resistant E. coli strains, resistance to tetracycline which was used most widely since 1951 was most frequently involved as a part of mutliple drug-resistance, followed by resistance to ampicillin and streptomycin. This strongly suggests that emergence of drug-restant strains in a community is directly dependent on the selective pressure exerted by the antimicrobial agent used. III. Cross resistance. Cross resistance of bacteria was studied among tetracycline penicillin, aminoglycoside and macrolide derivatives by analyzing correlation coefficients of sucseptibilities using the least square method. In this study, there were high correlations among the susceptibilities to related derivatives. It appears that the relatively low correlations in susceptibilities present in some cases are due to intrinsic resistance of E. aerogenes to penicillin, Enterococci to aminoglycoside and E. coli E. aerogenes and K. pneumoniae to macrolide derivatives.

• 자원환경지질
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• 제45권2호
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• pp.105-119
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• 2012

오염환경에 서식하는 토착미생물은 환경정화에 중요한 역할을 담당하며 이 연구는 6가 크롬 오염 지하수에서 분리한 미생물을 이용해 반응성, 이동성, 발암성 높은 6가 크롬을 당대사 조효소인 3가 크롬으로 환원/침전시켜 경제적, 친환경적, 생지화학적 정화의 효율성을 알아보았다. 미생물 농화배양과 조성분석, 호기와 혐기환경의 6가 크롬 환원과 내성, 전자공여체별 6가 크롬 환원, 지화학적 변화, 미생물 외형과 Cr((III) 침전물의 광물특성을 연구한 결과, 분리한 MMPH-0(Enterobacter aerogenes)는 혐기/호기환경에서 6가 크롬 내성과 환원능(유기산 주입 1주 후 70%, 주입 안한 경우 4주 후 10 ~ 20%)이 있고, Eh는 미생물의 유기산 산화로 생성된 전자에 의해 산화에서 환원환경, pH는 중성에서 약산성으로 변화되어 $Cr(OH)_3$/Cr(III)침전물이 형성되었다. SEM/TEM-EDS 결과 $2{\sim}5{\mu}m$ 막대형 미생물과 세포 밖 Cr(III) 침전물은 지화학적 환경변화와 유기산 산화에 따른 전자공여에 의한 환원의 근거가 된다. 지화학적 촉매제 토착미생물의 활성화로 산화환원에 민감한 중금속 오염 지하수 정화에 효율적 기술 응용이 기대된다.

• Journal of Microbiology
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• 제33권4호
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• pp.328-333
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• 1995

$\^$31/ P-NMR experiment was performed to detect phophonates (Pn) utilization and degradation in the several different C-P lyase mutants of E. coli and in E. aerogenes and the recombinants. The relative peak intensity (RPI) for the standard samples of 0.5 mM methylphosphonate (MPn) and 1.0 mM aminoethylphosphonate in glucose-MOPS medium showed 0.5 : 1.0 ratio. In the case of BW14329 (.DELTA.phnC-P, .delta.phoA), RPI did not change significantly after 24 hrs culturing, which means it nearly could not utilize Pn. In vivo $\^$31/ P-NMR spectrum of E. aerogens (BWKL 16627) during 3 hrs starvation showed two intense peaks at 0-2 ppm and at near-10 ppm which indicate intracellular orthophosphate (Pi) and pyrophosphate (PPi), respectively. Both of them might be released by degradation of inorganic polyphosphate pool. When MPn is supplied to the medium as an unique P source, Pi content in the cell has the constant, but PPi seems to be slightly decreased. Recombinants (BWKL 16954) grew slower than E. aerogenes in the glucose-MOPS media with various P sources. In vivo $\^$31/ P-NMR spectrum of recombinant did not show any intense signal in the cell. Surprisingly, under the cultivation adding with MPn, a few intense peaks in the region of Pi AND phospate monoester were detected.