• 한국미생물·생명공학회지
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• 제1권1호
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• pp.19-23
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• 1973

Penicillin을 농도별로 첨가한 Bouillon medium에서 배양한 Bacillus subtilis의 성장상태와 세포내미세구조를 전자현미경으로 관찰하여 다음과 같은 결과를 얻었다. 1. penicillin의 농도가 높아짐에 따라 본균의 성장이 현저하게 억제되고 분열된 세포일지라도 분리가 잘 되지않고 서로 융합되어 있다. 2. Cell wall 및 cell membrane 성장에 저해를 일으켜 septa형성이 불가능하다. 3) 세포질은 증가하나 세포막의 형성저해로 인하여, 세포가 팽대되어 세포막이 파열되며, 세포질이 세포외로 유출되어 내부가 공백상태로 된다. 따라서 그 기능을 상실하게 되는 것 같다.

• Journal of Microbiology and Biotechnology
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• 제7권3호
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• pp.194-196
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• 1997

Using the polyclonal antibody for Xanthomonas citri ampicillin acylase raised in Pseudomonas-free Balb/c mice, the immunochemical similarity of several types of penicillin acylases including Erwinia aroideae penicillin V acylase, Escherichia coli penicillin G acylase, Pseudomonas melanogenum and Acetobacter turbidans ampicillin acylases, and Pseudomonas cephalosporin acylase was examined. Among tested, only P. melanogenum ampicillin acylase showed the cross-reactivity with the antibody.

• 약학회지
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• 제18권3호
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• pp.209-216
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• 1974

From the measurements of infrared and fluorescence spectra riboflavin-2',3',4',5'-tetraacetate has been found to associate with penicillin-V more than strongly with themselves. They form the 1 : 1 cyclic hydrogen bonded dimer through the imino and the 2-C carbonyl groups of the isoalloxazine ring and the imino group of the penicillin-V ressidue. Pernicillin-V is an effective quencher of the fluorescence of riboflavin through hydrogen bonds partly due to the collision interaction with the penicillin ring.

• International Journal of Oral Biology
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• 제40권1호
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• pp.35-39
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• 2015

Minimal inhibitory concentration (MIC) is the lowest concentration of antibiotics that inhibits the visible growth of bacteria. It has been reported that sub-MIC of antibiotics may result in morphological alterations, along with the biochemical and physiological changes in bacteria. The purpose of this study was to examine morphological changes of Aggregatibacter actinomycetemcomitans, after the treatment with sub-MIC metronidazole and penicillin. The bacterial morphology was observed with scanning electron microscope, after incubating with sub-MIC antibiotics. The length of A. actinomycetemcomitans was increased after the incubation with sub-MIC metronidazole and penicillin. Sub-MIC metronidazole and penicillin inhibited bacterial division and induced long filaments. Our study showed that metronidazole and penicillin can induce the morphological changes in A. actinomycetemcomitans.

• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.2990-2994
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• 2014

The studies on design and synthesis of new monocyclic ${\beta}$-lactam esters 4(R/S)-(1'-methoxycarbonylpropyl- 2'(R/S)-thio)-3(R)-phenylacetamidoazetidin-2-one (3a) and 4(R/S)-(1'-methoxycarbonyl-2'-methylpropyl-2'- thio)-3(R)-phenylacetamidoazetidin-2-one (3b) were described. Compounds 3a and 3b were specifically designed to retain all penicillin substructures except the bicyclic system, which would be conceived by cleaving the C(3)-N(4) bond of penicillin G. Compounds 3a and 3b are of particular interest in the context of the structural elucidation of monocyclic ${\beta}$-lactams originated from penicillin. Key intermediates, ${\beta}$-mercapto esters 6a and 6b, were synthesized from conjugate acids 4a and 4b using three-step synthetic sequences, respectively, and 4(S)-acetoxy-3(S)-phenylacetamidoazetidin-2-one (7) was obtained from the degradation of penicillin G. Reactions of 6a and 6b with 7, thus obtained, provided the target compounds 3a and 3b, respectively.

• 한국미생물·생명공학회지
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• 제36권4호
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• pp.314-319
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• 2008

Penicillin G amidase(PGA, benzylpenicillinamidohydrolase, EC 3.5.1.11)는 penicillin G를 phenylacetic acid(PAA)와 6-aminopenicillanic acid(6-APA)로 분해하는 효소이다. Escherichia coli(E. coli) ATCC 11105의 PGA는 24 kDa의 small subunit과 65 kDa의 large subunit으로 구성되어 있고, precursor polypeptide에서 signal peptide와 spacer peptide가 절단되어 활성을 가진 heterodimer가 형성된다. 본 연구에서는 E. coli ATCC 11105에서 PCR(polymerase chain reaction)을 통해 증폭한 pga gene을 expression vector에 넣어 pET-pga plasmid를 제작하였고, 이것을 E. coli BL21 (DE3) 균주에 형질 전환하여 PGA를 발현하고 그 활성을 분석하였다. E. coli BL21(DE3)/pET-pga 균주의 고밀도 배양액을 SDS-PAGE로 분석 했을 때, PGA의 precursor, large subunit, 그리고 small subunit으로 보이는 protein band가 나타났으며, PGA가 soluble form의 precursor로 발현되어 processing을 거쳐서 large subunit과 small subunit으로 절단되기도 하고, 일부는 insoluble form의 precursor로 발현되기도 하는 것으로 생각된다. 유가배양시 온도변화 전략을 사용하여 고농도 배양에서 발현을 유도하였다. 온도변화 전략은 $37^{\circ}C$에서 $28^{\circ}C$를 거쳐 $22^{\circ}C$로 3단계로 변화시켰다. 이러한 전략으로 PGA활성은 19.6 U/mL이며 균체량은 600 nm에서 흡광도가 62까지 도달하였다.

• Pediatric Infection and Vaccine
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• 제5권2호
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• pp.215-220
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• 1998

목 적 : A군 연쇄구균 무증상 감염자는 증상은 없지만 A군 연쇄구균이 분리되고 ASO(antistreptolysin O)치가 높은 사람으로서 이들은 류마티스열이나 사구체신염 등 후유증을 일으킬 수 있다. 저자들은 무증상 감염자를 대상으로 경구용 페니실린을 복용하게 하여 이들에서 페니실린 치료 효과를 조사하였다. 방 법 : 상기도 감염 증상이 없는 건강한 초등 학생들을 대상으로 인두배양과 ASO치를 정량적으로 측정하였다. A군 연쇄구균이 분리되고 ASO 치가 400IU/mL 이상인 아동 36명을 대상으로 하여 그 중 22명의 학생은 경구용 페니실린 제제(penicillin V, 500mg. 하루 2회)를 10일간 복용하게 하였고, 14명은 대조군으로 삼고 항생제를 복용하지 않았다. 한달 후 두 그둡 아동에서 동시에 인두배양을 시행하여 A군 연쇄구균 제거율을 비교하고 ASO치를 측정하여 농도 변화를 관찰하였다. 결 과 : 항생제를 복용한 그룹과 복용하지 않은 그음의 A군 연쇄구균 제거율은 각각 91%(20/22)와 50%(7/14)로서 항생제를 사용한 그룹에서 유의하게 높았다(P<0.05). 항생제를 사용한 그룹과 사용하지 않은 그룹에서 ASO치가 100IU/mL 이상 상승한 경우는 각각 22%(4/18)와 30%(3/10)이었고 200IU/mL이상 감소한 경우는 각각 44.4%(8/18)와 40%(4/10)로서 유의한 차이가 없었다. 결 론 : 무증상 감염자를 대상으로 페니실린을 투여했을 때 인두에서 균이 효과적으로 제거되어 페니실린 치료의 타당성을 확인하였다. 그러나 ASO치 감소는 두 그룹간에 유의한 차이가 없었는데, 이는 ASO의 반감기가 걸고 경구용 페니실린의 경우 순응도가 낮기 때문으로 사료된다. 항생제 치료에도 불구하고 ASO치가 상승한 것을 치료 실패로 판정할 때 22%의 치료 실패율을 보였다.

• 대한치과의사협회지
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• 제52권7호
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• pp.425-431
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• 2014

Objectives : The purpose of our study was to evaluate penicillin as a still drug of choice for severe endodontic infection, by analyzing the antimicrobial susceptibilities from endodontic infections with swelling to figure out appropriate antibiotics as empirical treatment. Materials and methods : This study involved 18 patients who attended for emergency treatment because of facial or periapical swelling associated with root canal infections. Identification and antimicrobial susceptibility test of each pathogen were performed by Vitek2 Systems (bioM$\acute{e}$rieux, Marcy l'Etoile, France). Results : The most frequent bacteria was Streptococcus spp.(77%), and the resistance against penicillin was 35% in overall patients, followed by clindamycin and erythromycin (17%), which was much higher than previous studies. Conclusions : In our study, the higher resistance made penicillin alone not to be chosen as the first antibiotic drug for severe endodontic infections. Combinations with other drug, penicillin with wider spectrum of activity, or changing to other antibiotics was considered while remembering the increased risk of resistant microorganism.

• Journal of Microbiology and Biotechnology
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• 제14권1호
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• pp.62-67
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• 2004

The biosynthesis of cephalexin was carried out in the aqueous two-phase systems using penicillin acylase as a catalyst, and 7-aminodeacetoxicephalosporanic acid (7-ADCA) and phenylglycine methyl ester (PGME) as substrates. 20% PEG400-l7.5% ${(NH_4)}_2SO_4$ containing 0.5 M NaCl and 1.5 M methanol aqueous two-phase systems (ATPS) were selected as reaction medium, and 53% product yield was obtained using immobilized penicillin acylase as a catalyst. 20% PEG400-l5% $MgSO_4$ ATPS was also used for the synthesis of cephalexin, and 60-62% product yield was obtained by using free penicillin acylase as a catalyst. When batch reactions were repeated in the ATPS, the cephalexin yields decreased during the reactions due to deactivation, loss, and product inhibition of penicillin acylase. The effect of different ratio of phenylglycine methyl ester to 7-ADCA on the product yield was investigated, and high cephalexin yield was obtained at a high molar ratio.

• 대한수의학회지
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• 제13권1호
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• pp.57-62
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• 1973

The antibiotics are usually used for the medical treatments or the other purpose for cow and almost of them are transfered to milk. Moreover a serious problems on public health are caused by misuse or overuse of antibiotics. These studies were conducted to determine the rise and fall of antibiotics in the raw milk which is milked from the cow treated with antibiotics. The number of samples examined were 500 which were taken from 36 cows, and the antibiotics in milk were detected by cylinder plate assay method. The results were as follows: 1) When penicillin, chloramphenycol and streptomycin were infused into a udder, they were detected up to the period of 84 hours, 36 hours and 60 hours after injection in the milk from the same udder, however in the milk from the other udder streptomycin was not detected but penicillin and chloramphenycol were detected up to 72 hours and 24 hours after injection. When streptomycin and penicillin were injected intramusculary, streptomycin was not detected in the milk but penicillin was detected up to 60 hours after injcetion. 2) When penicillin, streptomycin and chloramphenycol were infused into the udder, the lesser amount of milk was produced, the more antibiotics were detected in the milk. 3) It is necessary policy for the public health to inhibit to be sold the milk up to 3 days or more after the injection on antibiotics or to add food blue to mastitis drugs.