• 한국식품위생안전성학회지
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• 제24권4호
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• pp.373-377
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• 2009

2008년 4월부터 2009년 1월 사이에 경기도 북부 지역에 위치한 축산 농가 15곳으로부터 458개의 원유 시료를 공급받아 장구균속 세균을 분리 동정하였다. 총 170개의 장구균속 세균이 분리되었으며 그 중 Enterococcus faecalis가 가장 우세하게 분리된 균주이며 (64.7%) E. faecium이 18.8%, E. avium이 5.9%, E. gallinarium이 5.9%, E. durans가 4.7%의 순으로 분리되었다. 분리된 170종의 장구균을 대상으로 ampicillin, erythromycin, tetracyclin, chloramphenicol, vancomycin, ciprofloxacin 및 streptomycin에 대한 감수성 검사를 실시하였다. 그 결과 erythromycin (82.9%)과 streptomycin (93.5%)에 대해서는 고도의 저항성을 나타내었으며 ampicillin (50%), chloramphenicol (45.(%) 및 tetracyclin (32%)에 대해서는 중증도의 저항성을 나타내었으나 vanocomycin 및 ciprofloxacin에 대해서는 다행이 감수성인 결과를 나타내었으며 앞으로도 지속적인 모니터링이 필요한 것으로 판단된다.

• 한국가금학회지
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• 제7권1호
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• pp.53-64
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• 1980

A total of 1503 specimens were submitted to the Poultry Disease Diagnostic Service Laboratory during the year 1966 and 1978. The most frequently diagnosed diseases in order of prevalence were avian mycoplasmosis, staphylococcosis, colibacillosis, salmonellosis and pullorum disease, the percentages of the conditions being 24.6%, 20.0%, 18.0%, 12.6% and 6.4%, respectively, The drug resistance of pathogenic mirnoorganisms isolated during the year 1978 from chicken with colicabacillosis, staphylococcosis or salmonellosis were investigated by the use of disc diffusion technique, the results being as follow. 1) Drug resistance of 63 strains of Escherichia coli More than 95% of the strains tested were sensitive to colistin and gentamicin. The percentages of strains sensitive to kanamycin, chloramphenicol, ampicillin and nitrofurantoin were 66.7%, 60.3%, 60.3% and 47.6%, respectively. Majority of the strains were highly resistant to streptomycin and tetracyline. All the strains were resisistant to bacitracin lincomycin, oleandomycin, penicillin and erythromycin. All the strains tested were resistant to more than two among 10 drugs in common use such as penicillin, erythromycin, streptomycin, tetracycline, neomycin, chloramphenicol, kanamycin, ampicillin and gentamicin, and 27 different resistance patterns were noted. The most frequent multiple resistance pattern was PC, EM, SM and TC (11.1%). 2) Drug resistance of 48 strains of Salmonella More than 95% of the strains tested were sensitive to colistin, gentamicin ana ampicillin. The percentages of st rains sensitive to kanamycin, tetracycline, neomycin and nitrofurantoin were 81,3%, 79%, 72.9%, and 68.0% respectively. None of them was sensitive to streptomycin, oleandomycin, erythromycin, lincomycin and bacitracin. All the strains were resistant to more than one among 7 drugs in common use such as streptomycin, erythromycin, neomycin, tetracycline, kanamycin, ampicillin and gentamicin. The most frequent resistance pattern was SM and EM(66.7%). 3) Drug resistance of 54 strains of Staphylococci All the strains tested were sensitive to gentmaicin, kanamycin and cephalothin. Majority of them were highly sensitive to bacitracin, methicillin, nitrofurantoin and chloramphenicol. The Percentages of strains sensitive to streptomycin, ampicillin, lincomycin and tetracycline were 66.7%, 55.6%, 44.4% and 27.8%, respectively. Among them, 51 strains were resistant to more than one among 11 drugs in common use such as tetracycline, lincomycin, ampicillin, penicillin, streptomycin, erythromycin, neomycin, oleandomycin, chloramphenicol, methicillin and bacitracin, and thirty one different resistance patterns were noted.

• 미생물학회지
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• 제42권2호
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• pp.156-159
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• 2006

Escherichia coli 16S rRNA의 잘 보존된 부분인 790 loop의 즉흥진화를 통한 분석에서 리보솜의 단백질 수행기능을 위해서 필수불가결한 것으로 추측되는 789번 위치에 염기치환을 유발하여 제작한 변이체 리보솜의 기능을 chloramphenicol acetyltransfernse mRNA의 단백질로의 번역능력 차이에 따른 chloramphenicol에 대한 저항성의 정도를 측정함으로써 분석하였다. 예상했던 바와 같이 모든 변이체 리보솜의 단백질 합성능력은 현저히 저하되었으며, 789 염기의 단백질합성에서의 기능을 규명하기 위하여 16S rRNA 변이체의 기능을 회복시키는 이차복귀돌연변이(second-site revertant)를 발췌하는 효과적인 유전학적 실험방법을 개발하였다.

• 미생물학회지
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• 제27권3호
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• pp.194-200
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• 1989

S. aureus에서 분리된 plasmid pSBK203 상의 CAT 유전자 염기서열을 결정하였으며 유발성 발현현상이 확인되었다. 염기서열 결과에 의해 예측된 단백질의 아미노산 서열 분석결고 pC221-CAT 와는 78%의 가장 높은 상동성을 나타냈으며 pC194-CAT와는 55%, 그람음성균 유래의 CAT 중 하나인 Tn9-CATdhkss 38%의 상동성을 각각 보여주고 있었다.

• Fisheries and Aquatic Sciences
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• 제19권7호
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• pp.31.1-31.6
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• 2016

Background: The objective of this study was to develop an efficient selectable marker for transgenic Dunaliella salina. Results: Tests of the sensitivity of D. salina to the antibiotic chloramphenicol and the herbicide Basta$^{(R)}$ showed that cells ($1.0{\times}10^6cells/ml$) treated with 1000 or $1500{\mu}g/ml$ chloramphenicol died in 8 or 6 days, respectively, whereas D. salina cells ($1.0{\times}10^6cells/ml$) treated with 5, 10, 20, or $40{\mu}g/ml$ Basta$^{(R)}$ died in 2 days. Therefore, D. salina is more sensitive to Basta$^{(R)}$ than to chloramphenicol. To examine the possibility of using the phosphinothricin N-acetyltransferase (pat) gene as a selectable marker gene, we introduced the pat genes into D. salina with particle bombardment system under the condition of helium pressure of 900 psi from a distance of 3 cm. PCR analysis confirmed that the gene was stably inserted into the cells and that the cells survived in $5{\mu}g/ml$ Basta$^{(R)}$, the medium used to select the transformed cells. Conclusions: The findings of this study suggest that the pat gene can be used as an efficient selectable marker when producing transgenic D. salina.

• BMB Reports
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• 제34권5호
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• pp.415-420
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• 2001

Chloramphenicol acetyltransferase (CAT) was purified to homogeneity from Morganella morganii starting with ammonium sulphate fractionation, followed by separation on DEAE-Sephadex A50, and G-100 Sephadex gel filtration. The enzyme was purified 133.3 fold and showed a final specific activity of 60 units/mg protein with a yield of 37%. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of the purified enzyme revealed it as a heterotetramer that consists of four subunits with close molecular weights (19.5, 19, 18, and 17.5 kDa). The molecular weight of the native enzyme was calculated to be 78 kDa, as determined by gel filtration, which approximated to that of the four subunits (74 kDa). The enzyme showed a maximum activity at pH 7.8 when incubated at $35^{\circ}C$. A Lineweaver-Burk analysis gave a Km of 5.0 uM and Vmax of 153.8 U/ml. The amino acid composition of the purified enzyme was also determined.

• Bulletin of the Korean Chemical Society
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• 제4권2호
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• pp.79-83
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• 1983

The structure of thiamphenicol, one of the congeners of chloramphenicol which is a well-known antibiotic, has been determined by single crystal x-ray diffraction techniques. The crystal structure was determined using diffractometer data obtained by the $2{\theta}:{\omega}$ scan technique with $MoK{\alpha}$ radiation from a crystal having space group symmetry $P2_{1}2_{1}2_{1}$, and unit cell parameters a = 5.779, b = 15.292 and c = 17.322 ${\AA}$ . The structure was solved by direct methods and refined by least squares to an R = 0.070 for the 2116 reflections. The overall V-shaped conformation of thiamphenicol revealed in this study is consistent with those from the crystallographic studies and the proposed models from the theoretical and nmr studies of chloramphenicol. However there is no intramolecular hydrogen bond and the propanediol moiety is fully extended in the thiamphenicol molecule, while the crystal structures of chloramphenicol show the existence of the hydrogen bond between the two hydroxyl groups of the propanediol moiety forming an acyclic ring. All of the thiamphenicol molecules in the crystal are linked by a threedimensional hydrogen bonding network.

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.2003-2010
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• 2010

A new class of halobenzyloxy or alkoxy 1,2,4-triazoles and their hydrochlorides were synthesized through cyclization starting from commercially available phenylhydrazine. The structures were characterized by MS, IR and $^1H$ NMR spectra as well as elemental analyses. All the synthesized compounds were screened for their antibacterial activities in vitro against Staphylococcus aureus (ATCC29213), methicillin-resistant Staphylococcus aureus (N315), Bacillus subtilis, Escherichia coli (ATCC25922), Pseudomonas aeruginosa, Shigella dysenteriae, Eberthella typhosa, and antifungal activities against Candida albicans (ATCC76615), Aspergillus fumigatus by broth microdilution assay method. The results of preliminary bioassay indicated that 3-(2,4-difluorobenzyloxy)-1-phenyl-1H-1,2,4-triazole hydrochloride exhibited the best inhibitory activity with an MIC value of 56.25 ${\mu}M$ against P. aeruginosa superior to Chloramphenicol, and showed comparable activity with Chloramphenicol against E. coli (ATCC25922).

• Natural Product Sciences
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• 제6권1호
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• pp.36-39
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• 2000

Acorenone, a diterpene isolated from Acorus gramineus, showed strong resistance inhibitory activity against multi-drug resistant microorganisms such as Staphylococcus aureus SA2, which has resistance to 10 usual antibiotics including chloramphenicol (Cm). At the level of $5\;{\mu}g/ml$ when combined with $50\;{\mu}g/ml$ of Cm. Bacterial resistance to Cm is due to the presence in resistant bacteria of an enzyme, chloramphenicol acetyltransferase (CAT), which catalyses the acetyl-CoA dependent acetylation of the antibiotic at C-3 hydroxyl group. To elucidate the mechanism of resistant inhibitory effect, the acorenone which had the strongest resistant inhibitory activity, was investigated on the CAT assay. As the result, the combination of Cm and acorenone showed the strongest inhibitory activity on CAT as noncompetitive and dose dependent manner.

• 한국미생물·생명공학회지
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• 제23권2호
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• pp.214-219
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• 1995

In fermentation of dairy products, bifidobacteria is used in conjunction with other lactic acid bacteria, such as L. acidophilus, L. bulgaricus and S. thermophilus, rendering the enumeration of bifidobacteria difficult. In order to develop optimum conditions for selective enumeration of bifidobacteria, we examined MIC of several antibiotics against various bifidobacteria and other lactic acid bacteria. The growth of L. acidophilus, L. bulgaricus and S. thermophilus were inhibited by lithium chloride at the concentration of less than 4 mg/ml, whereas growth inhibition of bifidobacteria occurred at concentrations over 6-10 mg/ml. Tetracycline and chloramphenicol were also found to selectively inhibit growth of other lactic acid bacteria at the concentration of 1-3 $\mu$g/ml. Addition of 6 mg/ml lithium chloride, 1 $\mu$g/ml, tetracycline or 3 $\mu$g/ml chloramphenicol to medium was found to be optimal for selective enumeration of bifidobacteria. By using these three inhibitory chemicals in the TPY medium, higher number of bifidobacteria were selectively isolated than with NPNL agar and LP agar.