• Journal of Microbiology
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• 제35권2호
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• pp.123-126
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• 1997

The aim of the present study was to optimize culture condition for the expression of lipocortin-1$_{1-185}$ in a recombinant of Escherichia coli using batch system. Plasmid (pHT22) carrying lipocortin-1$_{1-185}$ gene was well maintained in the recombinant with the addition of amplicillin as a selection pressures. Optimum temperature was 28$^{\circ}C$ for seed culture and 4$0^{\circ}C$ for main culture and the optimum pH was 7.0. The production of Lipocortin-1$_{1-185}$ was closely associated with cell growth and related to plasmid amplification.

• KSBB Journal
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• 제5권3호
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• pp.293-298
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• 1990

대장균의 lipoprotein promoter, lac UV5 promoter 및 operator와 lipoprotein의 signal sequence를 가지는 vector에 alpha-IFN유전자를 cloning함으로써 제작된 plasmid plF-III-B와 plF-III-C를 여러종류의 대장균 숙주 세포에 형질 전환하여 IFN의 생산성을 조사해 본 결과 $lpp^-$형질을 가지는 JE5505가 가장 우수했으며, 기존 plasmid, Hif-2h에 비해 130배 높은 생산성을 보였다. 또한 생산된 IFN의 약 50%가 세포 외부로 분비됨을 확인하였다.

• 한국미생물·생명공학회지
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• 제21권5호
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• pp.414-420
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• 1993

Escherichia coli mrdAts and mrdBts mutants forming spherical cells at 42C, were employed to investigate the possible role of both inner and outer membrance structures in the determination of cell shape of gram-negative cells. Spherical cells, but not rod-shaped wild types, were specifically killed by anionic detergents, such as sarkosyl, sodium dodecylsulfate and sodium deoxycholate. From the spherical intact cells grown overnight at 42C, much more proteins were released by sakosyl.

• 미생물학회지
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• 제8권2호
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• pp.65-68
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• 1970

In continuation of the previous work (The New Medical Journal, Vol. 12, No. 3, 111, 1969), the effects on the bactericidal activity against coli form group, on vitamin C content and ascorbate oxidase activity of the purple laver due to the $^{80}Co$ gamma-irradiation were studied. The results obtained are ; 1) After the 0.1m rad./hr. doses treatment of gamma-irradiation for 1 hours to the laver, the coli form group was being remarkably destoryed and after the application for 10 hours the coli form group was completely destroyed. 2) The content of vitamin C was gradually decreased during the gamma-irradiation to the laver. According to the sensory test, no changes in flavor nad color were indicated for 9-10 hours treatment. But, the loss of ascorbic was much than that of dehydroascorbic acid after 10-hour treatment. 3) And also, the ascorbate oxidase activity due to the irradiation waas conspicuously decreased.

• 한국산학기술학회논문지
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• 제18권5호
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• pp.667-673
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• 2017

본 연구는 그라비올라 (Graviola; Annona muricata Linn.) 잎의 항균소재 개발 목적으로 병원성 세균에 대한 항균효과를 검증하기 위해 시행된 실험 연구이다. 그라비올라 잎의 추출 온도를 $60^{\circ}C$, $80^{\circ}C$, $98^{\circ}C$ 달리하여 열수 추출하여 수율 및 추출 조건을 찾았으며 실험 균주 S. epidermidis, S. aureus 및 E. coli TOP 10에 대한 항균 활성은 한천 배지 확산법으로 평가하였다. 추출 온도 $60^{\circ}C$, $80^{\circ}C$, $98^{\circ}C$에서 3.02%, 14.73%, 20.76% 수율을 얻었고, S. epidermidis, S. aureus 및 E. coli TOP 10에 대한 항균 활성은 S. epidermidis에서 항균 활성이 나타났으며 $98^{\circ}C$에서 추출한 그라비올라 잎 시료 중 200 mg/mL에서 13 mm, 500 mg/mL에서 20 mm 투명환이 나타났다. MIC는 100 mg/mL이다. 추출 온도, 농도가 높을수록 우수한 성장억제효과를 확인하였다. 위 결과로 천연물속에 함유되어 있는 천연 항균 성분이 피부 상재균에서 우수한 항균력은 앞으로 피부미용 기초자료와 화장품 소재로서의 활용 가능성이 높을 것으로 사료된다.

• 생명과학회지
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• 제22권4호
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• pp.565-568
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• 2012

선식에 사용되는 곡류의 종류도 다양하고 오염미생물의 종류도 다양하여 곡류는 크기 모양 등을 고려하여 검정콩, 찹쌀, 수수의 3종류를 대상으로 피검균은 대장균을 인위적으로 오염시켜 세척조건에 따른 효과를 조사하였다. 초기 원료에 비해 세척횟수를 증가하여도 세척에 의한 오염균 감소효과는 없는 것으로 나타났다. 세척수량도 원료대비 200%의 경우가 오염균 감소에 약간 영향을 미치었으나 큰 효과는 나타나지 않았다. 세척 수 온도를 찬물이 아닌 $40^{\circ}C$의 물로 세척 시 1 log 이상의 오염균 감소효과를 보았다. 세척방법 시 염수를 첨가한 세척수의 사용 시 5% 정도가 적당하였으며 염수 처리 시 2 log 내지 3 log 정도의 감소효과를 관찰 하였다. 그러나 염류의 사용은 짠맛을 최종제품에 주게 되므로 염류를 제거하기 위한 세척공정이 추가로 필요하게 되며 완전한 염류의 제거를 위해서는 많은 양의 세척수량이 추가로 필요하게 된다.

• 미생물학회지
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• 제20권1호
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• pp.11-20
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• 1982

A study was undertaken to examine the effect of curing agents on the stability, curing and segregation of R plasmid pSL100. And also the stability, transfer frequency, and recombination of its segregants obtained from curing agent treatment were studied. Ethidium bromide, acridine orange, and mitomycin-C were used as curing agent. The results obtained were as follows ; 1. The curing agent ethidium bromide, acridine orange, and mitomycin-C were not effective for curing the multiple antibiotic resistant determinant of pSL100 in Salmonella typhimurium and Escherichia coli. However, they induced plasmid segregation with high frequency in S.typhimuruim LT-2strains. TcApSmCm, TcSmCmKm, TcApCm, TcAp, TcKm, Tc segregants were obtained. 2. The resistant markers of the segregents were transferred to S.typhimurium LT-2 strains with high frequencies whereas they were transferred to E.coli K-12 only with low frequencies. 3. The transconjugants obtained from conjugation between two different S.typhimurium segregants were similar to the phenotype of the original R factor pSL100 and the resistant markers were transferred to the S.typhimurium LT-2 or E.coli strain with equal frequencies, indicating that they are recombinants. 4. The transconjugants obtained from conjugation between pSL100 segrgants and pKM101, or pBR322 possessed the resistant markers of the two parental plasmids and they were transferred to both S.typhimurium and E.coli K-12 strains with the same frequencies and maintained stably, suggesting that they are also recombinants. 5. The recombinant pSL100 could be also obtained in rec A-strains of E.coli, suggesting that the gene function of rec A is required for the recombination of pSL100 segregants in E.coli.

• Journal of Microbiology and Biotechnology
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• 제27권5호
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• pp.965-974
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• 2017

The single-chain variable fragment (scFv) against lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a promising molecule for its potential use in the diagnosis and immunotherapy of atherosclerosis. Producing this scFv in several milligram amounts could be the starting point for further engineering and application of the scFv. In this study, the abundant expression of the anti-LOX-1 scFv was attempted using Escherichia coli (E. coli) and Brevibacillus choshinensis (B. choshinensis). The scFv had limited soluble yield in E. coli, but it was efficiently secreted by B. choshinensis. The optimized fermentation was determined using the Plackett-Burman screening design and response surface methodology, under which the yield reached up to 1.5 g/l in a 5-L fermentor. Moreover, the properties of the scFvs obtained from the two expression systems were different. The antigen affinity, transition temperature, and particle diameter size were 1.01E-07 M, $55.2{\pm}0.3^{\circ}C$, and 9.388 nm for the scFv expressed by B. choshinensis, and 4.53E-07 M, $52.5{\pm}0.3^{\circ}C$, and 13.54 nm for the scFv expressed by E. coli. This study established an efficient scale-up production methodology for the anti-LOX-1 scFv, which will boost its use in LOX-1-based therapy.

• 한국식품저장유통학회지
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• 제5권3호
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• pp.286-291
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• 1998

4종류의 식중독세균(Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus 196E, Salmonella typhimurium)에 대하여 녹차 물추출물에 의한 항균작용을 조사하였다. 각 식중독세균을 tryptic soy broth(TSB)에 약 $10^{5}$CFU/ml 정도 되게 접종하여 35$^{\circ}C$에서 30시간 배양하였다. 세균의 배양중 대수증식기의 중기 혹은 말기에 녹차 물추출물을 0-2%(w/v)의 농도로 첨가하였을 때 증식억제 정도를 생균수 변화로서 비교하였다. 식중독세균의 증식은 첨가한 녹차 물추출물의 농도에 비례하여 억제되었으며 대수증식기 말기의 세균이 중기의 세균에 비하여 녹차 물추출물에 대한 내성이 컸다. Gram 양성균(L. monocytogenes, S. aureus)의 경우가 Gram 음성균(E. coli O157:H7, S. typhimurium)에 비하여 녹차 물추출물에 의한 억제효과는 월등히 컸다. 녹차 물추출물에 의한 증식억제 효과의 크기는 S. aureus, L. monocytogenes, E. coli O157:H7의 순이었으며 S. typhimurium에서 가장 강한 내성을 나타내었다.다.

• 한국수산과학회지
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• 제42권4호
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• pp.322-328
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• 2009

Three-hundred and sixteen Escherichia coli strains from seawater, and a variety of farmed fishes, including oliver flounder (Paralichthys olivaceus), black rock fish (Sebastes schlegeli), red sea bream (Pagrus major) and sea bass (Lateolabrax japonicus) between May to October in 2004, were tested by agar dilution method to determine their susceptibility patterns to 17 antimicrobial agents. Overall, 92.1% of Escherichia coli isolates from samples showed antimicrobial resistance to at least one antimicrobial agent and the multiple resistance was seen in 173 isolates (54.7%). The resistance of E. coli isolates to tetracycline (74.1%) was highest, followed by cephalothin (69.9%), doxycycline (66.5%), streptomycin (47.2%), ampicillin (46.2%), cefazolin (31.6%), enrofloxacin (31.0%). norfloxacin (28.2%). The most frequent resistance pattern was TE-D-CF-CIP-ENO-NOR-AM-S-C-SXT-AmC-CZ (14.7%), followed by CF (6.2%), TE (5.1%), TE-CF (4.5%) in 177 isolates from fishes and TE-D-CF (7.2%) followed by TE-D-CF-S (5.8%), CF and TE-D-S (3.6%) in 139 isolates from seawater.