• 대한미생물학회지
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• 제14권1호
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• pp.49-61
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• 1979

Two hundred and ninety-five strains of Peudomonas aeruginosa isolated from clinical sources were tested for drug resistance and demonstration of R plasmids by intraspecies conjugation system. Sixty strains were found highly resistant to two or more of drugs. The rate of resistant strains were 38.9% to kanamycin(km), 33.2% to streptomydn(sm), 22.7% to sulfisomidine(Sa), 14.2% to chloramphenicol(Cp), 13.8% to tetracycline(Tc), 3.0% to carbenicillin(Cb), and to gentamicin(Gm), respectively. But no strains was resistant to nalidixic acid and colistine. They were resistant to per milliliter to more than $400{\mu}g$ per ml. of Tc, $800{\mu}g$ per ml of Cp and of Sm, $6,400{\mu}g$ per ml. of Sa, $200{\mu}g$ per ml. of Cb, $100{\mu}g$ per ml. of Gm, and $25{\mu}g$ per ml. of colistine. Forty-three strains of Pseudomonas aeruginosa could be transferred their resistance to Pseudomonas aeruginosa 2-70, 1005 rifampin resistant FP-auxotrophic mutant. Of sixty multiple resistant strains, forty-three(71.6%) demonstrated R plasmids; nineteen carried resistance to(Tc Cp Sm Sa), six to(Tc Cp Sm), three to(Tc Cp Sa), and Cp, five to(Tc Sm Sa), two to(Tc Sa), (Cp Sm) and Tc, and one to(Cp Sm Sa). Degree of resistance of recipients recieving R plasmids from donors were almost the same level of resistance as the donor in regardless of mating temperature at $25^{\circ}C$ and $37^{\circ}C$. Resistance to Tc, Sm, and Sa were transferred to a very few of recipient cells at five minutes after mating with donor and recipient cells but resistance to Cp were transferred to the majority of recipient cells. The transfer frequency of Tc, Cp, Sm, and Sa resistance from donors to recipients were from $1.0^{-1.4}\;to\;1.0^{-3.5}$ at $25^{\circ}C$ for 18 hours of incubation and were from $1.0^{-1.5}\;to\;1.0^{-3.5}$ at $37^{\circ}C$ for 18 hours of incubation.

• 대한미생물학회지
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• 제19권1호
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• pp.11-24
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• 1984

Shigella remains to be an important enteric pathogen in this country for the present. Moreover, most of the isolates have become multiple resistant to various antibiotics which used to be drugs of choice for shigellosis. This study was made as an attempt to assess the present stage of antibiotic resistance and the incidence and transferability of R factors of Shigella. A total of one hundred and seventeen strains of Shigella isolated from patients in Seoul and provincial area between 1982 and 1983 were tested for their resistant to antimicrobial agents and transmission of R-plasmid. Antibiotic susceptibilities were determined by an agar dilution method. Muller hinton agar were used for the assay of drug resistance and tryptic soy broth were used for propagating medium for conjugation. Shigella isolated found to be one or more antibiotics were considered potential donor of R-plasmid. The following results were obtained. 1. Among 117 strains of Shigella isolated, 111 strains(94.9%) were found to be resistant to one or more drugs tested and 97.3% of these resistant strains were multiply resistant, indicating the multiply resistant strains were more than the single resistant strains. Only six strains were susceptible to all drugs tested. 2. Among 117 strains of Shigella isolated, 107 strains(91.5%) were resistant to Tetracyclin(Tc), 106 strains(90.6%) to Chloramphenicol(Cp) and Streptomycin(Sm), 97 strains(82.9%) to Ampicillin(Ap), 68 strains(58.1%) to Cephaloridine(Cr), 10 strains(8.5%) to Nalidixic acid(Na), 5 strains(4.3%) to Kanamycin(Km) and 2 strains(1.7%) to Rifampicin. No strain was resisfant to Amikacin(Ak) and Gentamicin(Gm). 3. All drug-resistant Shigella strains, except three, were multiply resistant to two or more drugs. Fifty eight strains were resistant to five drugs, followed by 26 strains resistant to dour drugs, 12 strains resistant to three drugs and 11 strains resistant to six drugs. 4. The 73% of multiply drug-resistant Shigella transferred their resistance to E. coli by conjugation and the resistance was considered to be mediated by R-plasmid. Resistance to Nalidixic acid and Rifampicin were not transferred by conjugation to recipient. As for the transferability of resistance to each seperate drug, Ap resistance was transferred with 73.2% frequence and Cm and Tc resistance were transferred with approximately 50-60% frequence whereas Sm and Cr resistance were transferred in 19.1-21.4% The other four drugs resistant failed to transfer their resistance to recipient. 5. As for the incidence and transferability of resistance to each seperate drug, the strains resistant to Tc and Cm were encountered most frequently with the rate of 91-92%, whereas transfer of Tc and Cm were low, 51-52%. The incidence of Sm resistance was very high(90.6%) but transferability of drugs resistance was much lower(25.4%). Though the incidence of Km reristance was much lower(4.3%) transferability of Km resistance was considerably higher(60%). 6. The greater the multiplicity of resistance, the greater was the likelihood that part of all of the resistance markers would be transferable.

• 한국어병학회지
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• 제1권2호
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• pp.77-85
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• 1988

1987년(年) 3(월)月 부산수산대학(釜山水産大學) 어병학(魚病學) 실험실(實驗室)에서 사육중(飼育中)이던 틸라피아 (Oreochromis niloticus)에 세균성(細菌性) 질병(疾病)이 발생(發生)하여 만성적(慢性的)으로 몇마리씩 폐사(斃死)하였다. 본(本) 연구(硏究)는 이러한 질병(疾病)의 원인(原因)을 밝히기 위하여 원인균(原因菌)을 분리(分離)하였으며, 형태적(型態的), 생화학적(生化學的) 성상(性狀)을 관찰(觀察)하고 병원성(病原性), 약제감수성(藥劑感受性) 실험(實驗)을 하였으며 시험항원(試驗抗原)을 제작(制作)하여 그 항원성(抗原性)을 조사하였는바, 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 병어(病魚)에서 분리(分離)된 원인균(原因菌)은 Edwardsiella tarda로 동정(同定)되었다. 2. 분리균(分離菌)을 틸라피아에 접종하여 재현성실험(再現性實驗)을 한 결과(結果) 전형적인 E. tarda의 감염증상을 나타내고 사망(死亡)했으며, 어류(魚類)로부터 동일균(同一菌)을 얻을 수 있었다. 3. 분리균(分離菌)은 oxytetracycline에서 감수성(感受性)이 높았고, MIC는 6.9로 나타났다. 4. 분리균(分離菌)은 병원성(病原性)이 강한 균(菌)이었으며, 48-LD50은 $10^{6.4}cell$/fish 이었다. 5. 시험항균(試驗抗原)으로, 포르말린사균항원, 초음파처리항원, 균여과액항원을 사용하였으며, 이 세가지를 사용한 항원성시험(抗原性試驗) 결과 포르말린사균항원의 시험구에서 높은 응집가와 방어력을 나타내었다.

• 대한수의학회지
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• 제26권2호
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• pp.229-235
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• 1986

1984년 5월부터 1985년 5월까지 대구(大邱), 경북(慶北), 경남(慶南) 및 충남지역(忠南地域) 7개(個) 양돈장(養豚場)의 자돈(仔豚) 및 성돈(成豚)의 분변(糞便) 및 양돈장(養豚場)의 흙, 하수(下水), 사료(飼料), 추비(推肥), 쥐 등 7,440예(例)와 대구시(大邱市) 도축장(屠畜場)의 도축돈(屠畜豚) 장간막임파절(腸間膜淋巴節) 및 직장내용물(直腸內容物) 555예(例)로부터 분리(分離)한 319주(株)의 Salmonelia속균(屬菌)을 대상으로 항균제(抗菌劑)에 대한 내성(耐性) 및 전달성(傳達性) R plasmid의 분포상황(分布狀況)을 조사(詞査)하였던 바 그 결과(結果)는 다음과 같다. 1. 공시균(供試菌) 319주(株) 중(中) 250주(株)(78.4%)가 ampicillin(An), chloramphenicol(Cm), gentamicin(Gm), kanamycin(Km), nalidixic acid(Na), rifampicin(Rf), streptomycin(Sm), sulfadimethoxine(Su), 또는 tetracycline(Tc)에 내성(耐性)을 나타내었으며, 약제별(藥劑別)로는 Su(74.9%), Sm(53.0%) 및 Tc(28.5%)에 높은 내성(耐性)이 인정(認定)되었다. 2. 내성균(耐性菌) 250주(株)의 전달성(傳達性) R plasmid 보유율(保有率)은 51.2%(128주(株))였으며, 약제별(藥劑別)로는 Am경우 100%, Tc 92. 3% 및 Cm 75.0% 순으로 보유율(保有率)이 높았다. 3. 내성균(耐性菌) 250주(株)의 내성양상(耐性樣相)은 SmSu(91주(株)), Su(59주(株)) 및 TcSmSu(50주(株))내성형(耐性型)이 대부분이었고 R plasmid 전달후(傳達後)의 내성양상(耐性樣相)은 TcSmSu(40주(株)) 및 TcSu(28주(株)) 내성형(耐性型)이 많았다. 4. 양돈장별(養豚場別) 내성균(耐性菌) 출현빈도(出現頻度)는 48.0~93.6%로 다양(多樣)하였고, 전달성(傳達性) R plasmid 보유율(保有率)은 0~77.8%로 내성균(耐性菌) 출현빈도(出現頻度)와 일치(一致)되지 않았다. 5. 공시균(供試菌) 319주(株) 중(中) 각각(各各) 2주(株)는 Rf 및 Gm에 대해 내성(耐性)을 나타내었고, 내성균(耐性菌) 250주(株) 중(中) 73.2%(183주(株))가 다제내성(多劑耐性)이었으므로 Salmonella의 다제내성화(多劑耐性化) 경향(傾向)이 있었다. 6. 내성균(耐性菌) 250주(株) 중(中) R plasmid 전달후(傳達後) 5주(株)는 TcAmCmSmSu내성형(耐性型), 1주(株)는 TcAmKmSmSu내성형(耐性型)임이 확인되었다.

• 대한수의학회지
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• 제26권2호
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• pp.283-292
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• 1986

Isolation and identification of Mycoplasma were performed to clarify Mycoplasma infection of mice fed by conventional feeding at two ($K_1$, $K_2$) institutes in Korea. The twenty mice to be tested were randomly sampled from each of 10 breeding colonies in respective institute. Identification of the Mycoplasma strains isolated from the nasal cavity, lung and synovia of mice was made according to the morphology of colonies, biological and biochemical properties with special reference to M. pulmonis, M. arthrotodis and M. neurolyticum. In addition, growth inhibition test was performed using hyperimmune rabbit antisera to the strain PG-22 of M. pulmonis, the strain PG-6 of M, arthritidis and the strain PG-28 of M. neurolyticum and also differentiation of isolates from L-form bacteria was dont by Dieses staining and culture method with passage of the isolates on liquid media eliminated antibacterial drug. On the other hand, a total of 13 strains out of the 44 isolated M. pulmonis from mice was investigated for their susceptibility against 16 antibiotics in vitro. The antibiotic sensitivity test was made using $3{\times}10^4$ organisms/0.3ml on each plate(90mm diameter) with antibiotic mono-or tri-disk. The results obtained are summarized as follows: 1. Out of 20 mice from 10 breeding colonies in Kl institute, mycoplasma-like strains from the nasal cavity of 16 mice(80%) and from the lung of 8 mice(40%) were isolated, while out of 20 mice in K2 institute, M-like strains were isolated from the nasal cavity of 14 mice(70%) and from the lung of 6 mice(30%). However, no mycoplasma-like organisms were isolated from the synovia of the 40 mice examined. All the 44 strains isolated were identified as the organisms of M. pulmonis. 2. Out of the 16 antibiotics tested, penicillin, oleandomycin and bacitracin showed no activity against all the 13 M. pulmonis strains. On the contrary, lincomycin, clindamycin, chloramphenicol, tetracycline, minocycline, kanamycin, gentamycin and tobramycin showed high activity with three different antibiotic concentration of tridisk, but amikasin and spiramycin showed intermediate activity. Other antibiotics such as polymyxin B and colistin showed low activity, while erythromycin showed lower activity than others.

• 미생물학회지
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• 제31권1호
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• pp.17-21
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• 1993

Bacillus thuringiensis를 한국의 토양에서 분리하여 특성을 연구했다. 8균주를 분리하여 HL-24, HL-25, HL-33, HL-34, HL-35, HL-38, HL-39와 HL-40으로 명명했으며. HL-24와 HL-25는 부정형의 crystal를 가졌고, HL-33과 HL-35는 이중피라미드형, HL-34. HL-38, HL-39와 HL-40은 둥근형의 crystal를 가진 것을 위상차현미경으로 관찰했다. 분리균들의 생화학적인 특성은 이미 알려진 균주들과 유사했으나. 특이한 차이점을 가지고 있었다. HL-25, HL-33과 HL-34는 cephalothin, colistin과 penicillin G에 내성을, HL-33과 HL-35균주는 chloramphenicol에 내성을 HL-39와 HL-40은 penicillin G에 내성을 나타냈다. 균주HL-24, HL-25, HL-33과 HL-34는 누에 유충에 대한 치사성은 100.85.55. 및 70%를 각각 나타냈으며 HL-24, HL-25, HL-38, HL-39와 HL-40의 모기 유충에 대한 치사성은 10. 20. 100. 100 및 90%였다. HL-24와 HL-25균주는 누에와 모기 유충에 모두 치사성은 나타냈으나. 모기에는 살충효과가 10~20%로 매우 낮았다.

• Journal of Microbiology and Biotechnology
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• 제23권4호
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• pp.545-554
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• 2013

Plasmid isolation of kimchi-derived Weissella cibaria KLC140 revealed six different plasmids. The smallest plasmid, pKW2124, was DNA sequenced and characterized, showing 2,126 bp with a GC content of 36.39% and five putative open reading frames (ORFs). In silico analysis of these ORFs showed ORF1 encodes a putative replication protein similar to rolling circular replication proteins from other lactic acid bacteria. However, a single-stranded intermediate was not detected when S1 nuclease was treated, suggesting it may follow theta replication. Interestingly, the replication initiation site of this plasmid is 100% identical to other plasmids from lactic acid bacteria, suggesting it may function for replication initiation. To construct a surface layer expression vector, pTSLGFP, slpA encoding the surface layer protein from Lactobacillus acidophilus was PCR amplified and fused with the gfp gene, forming a SLGFP fused gene. The plasmid pKW2124 was cloned into the XbaI site of pUC19, forming an Weissella-E. coli shuttle vector pKUW22. NheI-linearized pTSLGFP was ligated into pKUWCAT containing pKUW22 and the chloramphenicol acetyltransferase gene from pEK104, resulting in an 8.6 kb pKWCSLGFP surface layer expression vector. After transformation of this vector into W. cibaria KLC140, a GFP fluorescence signal was detected on the surface of the transformant, substantiating production of SLGFP fused protein and its secretion. This is the first report for construction of a Weissella surface layer expression vector, which may be useful for surface layer production of beneficial proteins in Weissella.

• Genomics & Informatics
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• 제2권4호
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• pp.174-179
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• 2004

We developed various plasmid cloning vectors that are useful in the construction of genomic and shotgun libraries. Two medium copy vectors, pCUGlblu21 (pCb21) and pAGlblu21 (pAb21), which are resistant to kanamycin ($Km^R$) and chloramphenicol ($Cam^R$), respectively, are useful for cloning DNA inserts ranging from 5kb to 15kb. Two high copy vectors, pCUGlblu31 (pCb31) and pAGlblu31 (pAb31), containing $Km^R$ and $Cam^R$, respectively, are useful for DNA inserts less than 5kb. These vectors are well adapted for large-scale genome sequencing projects by providing choice of copy number and selectable marker. The small vector size is another advantage of these vectors. All vectors contain lacZa including multicloning sites that originated from pBluscriptllsk- for easy cloning and sequencing. Two medium copy vectors contain unique and rare cutting Swal (ATTTAAAT) restriction enzyme sites for easy determination of insert size. We developed two combined vectors, pC21A31 and pC31A21, which are combinations of (pCb21 + pAb31) and (pCb31 + pAb21), respectively. These two vectors provide four choices of vectors such as $Km^R$ and medium, $Cam^R$ and high, $Cam^R$ and medium, and $Km^R$ and high copy vectors by restriction enzyme cutting, dephosphorylation, and gel purification. These vectors were successfully applied to high throughput shotgun sequencing of rice, tomato, and brassica BAC clones. With an example of extremely biased hydro sheared 3 kb shotgun library of a tomato BAC clone, which is originated from cytogenetically defined peri-centromeric region, we suggest the utility of an additional 10 kb library for sequence assembly of the difficult-to-assemble BAC clone.

• 대한치과보철학회지
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• 제41권2호
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• pp.207-222
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• 2003

As a material of metal-ceramic prosthesis, nickel as a form of Ni-Cr alloy has been used for many dental prostheses in many cases. However, several problems in use of the alloy have been revealed (ex ; tissue stimulation, skin allergy, hypersensitivity cytotoxicity and carcinogenecity). Little is known about nickel with respect to the relationship between Ni-prosthesis and gaining of Niresistance in oral microorganisms. The present study was undertaken to check whether use of Ni-prosthesis leads to occurrence of Ni-resistant microorganisms. So this study may suggest the possible relationships between the oral microorganisms and nickel-resistance in oral environment. Bacteria were isolated from the gingival crevicular fluid on the patients wearing Ni-Cr prosthesis. The isolated bacteria were tested fir their Ni-resistance in nickel containing media at different concentration from 3mM to 110mM. E. coli HB101 was used as control. The Ni-resistant bacteria were isolated and biochemically identified. The Ni-resistant bacteria were tested several biochemical, molecular-biological tests. Performed tests were : measuring the growth curve, antibiotic test, growth ability test in liquid media, isolation of the chromosome and plasmid, digestion of DNA by restriction enzyme, electrophoresis of chromosome and plasmid DNA, identification of Ni-resistant genes by the DNA hybridization. The results were as follows 1) The bacteria isolated from gingival crevicular fluid on the patients wearing Ni-Cr alloy prosthesis showed nickel-resistance. 2) The isolated microorganisms grew at nickel containing media of high concentrations (60mM-110mM). 3) Based on the biochemical tests, the isolated microorganisms were identified as Enterococcus faecalis(13 cases), Klebsiella pneumoniae(1 case) and Enterobacter gergoviae(1 case). 4) Enterococcus faecalis expressed not only nickel resistance but also the multi-drug resistance to several antibiotics ; chloramphenicol, kanamicin, streptomycin, lincomycin, clindamycin, However, all strain showed the sensitivity against the tetracycline. 5) DNA hybridization result suggests that there is no homology between the previously known gene of nickel resistance in Klebsiella pneumoniae and chromosomal DNA of Enterococcus faecalis.

• 한국균학회지
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• 제12권4호
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• pp.183-188
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• 1984

서울에서 1983년 12월 26일부터 1984년 2월 11일 까지 각종 건물실내환경에서 채취한 진균을 배양분리한 결과에서 다음과 같은 결론을 얻을 수 있었다. 총 26종류의 진균이 검출되었다. 병원에서는 14종류의 진균이 검출되었는데, 이중에서 Cladosporium sp.와 Penicillium sp.가 주종을 이루며 Alternaria sp., Chaetomium sp. 그리고 효모등이 비교적 많이 검출되었다. 일반주택에서는 22종류의 진균이 검출되었으며, 여기서는 Penicillium sp.가 상당분을 차지하고, Alternaria sp., Aspergillus sp., Cladosporium sp., Rhizopus sp., Trichoderma sp.가 주종을 이룬다. 아파트에서의 진균종류도 대체로 주택과 같았다. 이 조사에서는 특별히 진균의 정량적인 분석이 이루어지지 않았으므로 확실한 위해도의 여부는 가리기 힘들다. 따라서 이들 진균을 종까지 분류하고 각각에 대한 정량분석을 하여 공중위생적인 위해도와의 관계를 추정하는 조사가 앞으로 요망된다. 이상에서 진균성 식중독을 유발하는 균의 분포가 보편적으로 인정되므로, 분포가 넓은 여러 종의 진균에 대해서는 실내 환경내에서 오염 또는 증식되지 않도록 하는 대책이 필요하다. 또한 많은 사람이 모이는 공중 장소에 대해서는 검출되는 진균의 종류에 대하여서는 적절한 위생적인 규제가 있어야 하겠다.