• Journal of Microbiology and Biotechnology
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• 제11권1호
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• pp.164-166
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• 2001

To examine the characteristics of the recombinant thin aggregative fimbriae of Salmonella, the AgfA subunit gene was amplified from Salmonella enteritidis using a PCR. The maltose binding protein (MBP)-AgfA fusion protein was overproduced in E. coli and purified. The secondary structure of AgfA was then elucidated from the difference CD spectra. An estimation of the secondary structure of AgfA using the self-consistent method revealed a mostly ${\beta}-sheet$ structure.

• 생명과학회지
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• 제31권3호
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• pp.330-337
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• 2021

본 연구에서는 천연물유래 구강건강 개선소재로써 노각나무의 이용 가능성을 알아보기 위해 노각나무 잎과 줄기를 에탄올에 추출한 다음 구강미생물에 대한 추출물의 항균활성을 조사하였다. 노각나무 잎과 줄기 추출물(1 mg/disc)은 구강미생물 중 P. gingivalis KCTC5352에 대해서만 항균활성을 나타내었으며 줄기보다는 잎 추출물의 항균활성이 우수하였다. 시판되고 있는 구강케어제품에 사용되고 있는 항균제와 노각나무 잎 추출물의 항균활성을 비교한 결과, P. gingivalis에 대한 노각나무 잎 추출물과 양성대조구로 사용한 triclosan의 항균활성은 유사하게 나타났으며. P. gingivalis에 대한 노각나무 잎 추출물의 MIC는 0.4 mg/ml이고 정균작용을 하였다. 노각나무 잎추출물이 0.2-2.0 mg/ml 농도로 처리된 배양액에서 P. gingivalis KCTC5352의 생물막 형성과 세균 생육은 추출물의 농도가 증가할수록 농도의존적으로 억제되는 경향을 보였다. 또한 노각나무 잎 추출물(1 mg/ml) 처리가 P. gingivalis의 생물막 형성에 미치는 영향을 주사전자현미경으로 관찰한 결과에 의하면 추출물을 처리하지 않은 대조구는 추출물 처리구에 비해 P. gingivalis가 군집을 이루며 모여 있었고 세포 주변에서 생물막이 관찰되었지만 추출물을 처리한 처리구의 세포 주변에서는 생물막을 관찰할 수 없었다. qRT-PCR을 이용하여 생물막 형성 초기 과정에서 치면 부착에 필수적인 섬모(fimbriae)관련 mRNA 발현 양상을 0조사한 결과, 노각나무 잎 추출물이 0.2-2.0 mg/ml의 농도로 처리된 배양액에서 fimA와 mfa1 유전자 발현은 추출물의 농도가 높아질수록 농도의존적으로 억제되는 것을 확인할 수 있었다. 이상의 결과를 종합하면 노각나무 잎 추출물은 치주질환 원인균인 P. gingivalis에 대한 항균 활성과 생물막 형성 억제능이 우수하기 때문에 천연물유래 구강건강 개선소재로써 이용 가능성이 높을 것으로 판단된다.

• Journal of Microbiology
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• 제44권5호
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• pp.548-555
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• 2006

FaeG is the key factor in the infection process of K88ad enterotoxigenic Escherichia coli (ETEC) fimbrial adhesin. In an attempt to determine the possibility of expressing recombinant FaeG with immunogenicity for a new safe and high-production vaccine in E. coli, we constructed the recombinant strain, BL21 (DE3+K88), which harbors an expression vector with a DNA fragment of faeG, without a signal peptide. Results of 15% SDS-polyacrylamide slab gel analysis showed that FaeG can be stably over-expressed in BL21 (DE3+K88) as inclusion bodies without FaeE. Immunoglobulin G (IgG) and M (IgM) responses in pregnant pigs, with boost injections of the purified recombinant FaeG, were detected 4 weeks later in the sera and colostrum. An in vitro villius-adhesion assay verified that the elicited antibodies in the sera of vaccinated pigs were capable of preventing the adhesion of K88ad ETEC to porcine intestinal receptors. The protective effect on the mortality rates of suckling piglets born to vaccinated mothers was also observed one week after oral challenge with the virulent ETEC strain, $C_{83907}$ (K88ad, $CT^+,\;ST^+$). The results of this study proved that the adhesin of proteinaceous bacterial fimbriae or pili could be overexpressed in engineered E. coli strains, with protective immune responses to the pathogen.

• 미생물학회지
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• 제47권4호
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• pp.335-341
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• 2011

본 연구에서는 병원 감염의 주요 원인균으로 생물막 관련 감염증에서 흔히 분리되고 있는 Citrobacter, Enterobacter 및 Serratia 등의 임상분리 장내세균 22주를 대상으로 생물막 형성능을 조사하고, 생물막의 세포외 바탕질의 구성 성분을 알아보기 위하여 Congo-red 한천배지상의 집락 형상과 calcofluor 염색을 시행하였다. 또한 curli 생성 오페론인 csgBA(C) 유전자의 유무 확인과 csgA 유전자의 염기서열을 규명하였다. $37^{\circ}C$에서 24시간 배양 후 생물막 형성능 분석에서는 2주의 S. marcescens를 제외한 나머지 20주는 모두 생물막 형성능이 있는 것으로, $28^{\circ}C$에서 48시간 배양 후 분석에서는 22주 모두 생물막 형성능이 있는 것으로 확인되었다. Congo-red 한천배지에서의 균집락 형상을 조사한 결과 균속에 따라서 균 집락의 표현형상이 다르게 나타났으며, 동일 균속내에서도 균 집락의 표현형상과 색 농도의 차이가 관찰되어 세포외 바탕질의 주요 성분 및 생성량의 차이가 있음을 시사하였다. 1주의 C. freundii와 4주의 E. cloacae에서 csgBA(C) 유전자 양성을 나타내었다. 염기서열 분석결과, E. cloacae의 csgA는 E. coli의 csgA와 80.9%, E. sakazakii의 csgA와 75.7%, 그리고 C. freundii의 csgA와 67.8%의 상동성이 있는 것으로 나타났다. E. cloacae의 경우 Congo-red 염색의 결과와 curli 유전자 검색 결과가 일치하였을 뿐만 아니라, csgA 유전자를 보유하지 않은 균주의 생물막 형성능이 csgA 유전자를 보유한 균주에 비해 현저하게 낮은 것으로 나타나, curli가 E. cloacae의 생물막 세포외 바탕질 구성성분의 주요 요소일 것으로 추정되었다.

• Journal of Animal Science and Technology
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• 제62권4호
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• pp.543-552
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• 2020

For efficient prevention and treatment of enteric colibacillosis, understanding about latest virulence factors and antimicrobial resistance of Escherichia coli is essentially needed. The aim of this study was to survey antimicrobial resistance and determine the prevalence of fimbriae and enterotoxin genes among 118 pathogenic E. coli isolates obtained from Korean pigs with diarrhea between 2016 and 2017. The genes for the toxins and adhesins were amplified by polymerase chain reaction (PCR). The susceptibility of the E. coli isolates to antimicrobials were tested using the standard Kirby-Bauer disk diffusion method. The most prevalent fimbrial antigen was F18 (40.7%), followed by F4 (16.9%), and the most prevalent combinations of toxin genes were Stx2e (21.2%), STb:EAST-1 (19.5%), and STa:STb (16.9%), respectively. Among the pathotypes, enterotoxigenic E. coli (ETEC) was the most predominant (67.8%), followed by Shiga-toxin producing E. coli (STEC, 23.7%). We confirmed high resistance rates to chloramphenicol (88.1%), tetracycline (86.4%), streptomycin (86.4%), and ampicillin (86.4%). And the majorities of isolates (90.7%) showed multi-drug resistance which means having resistance to 3 or more subclasses of antimicrobials. Results of this study can be a source of valuable data for investigating the epidemiology of and control measures for enteric colibacillosis in Korean piggeries.

• Journal of Microbiology and Biotechnology
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• 제27권3호
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• pp.542-551
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• 2017

Small phytochemicals have been successfully adopted as antibacterial chemotherapies and are being increasingly viewed as potential antibiofilm agents. Some of these molecules are known to repress biofilm and toxin production by certain bacterial and yeast pathogens, but information is lacking with regard to the genes allied with biofilm formation. The present study was performed to investigate the inhibitory effect of burdock root extract (BRE) and of chlorogenic acid (CGA; a component of BRE) on clinical isolates of Klebsiella pneumoniae. BRE and CGA exhibited significant antibiofilm activity against K. pneumoniae without inflicting any harm to its planktonic counterparts. In vitro assays supported the ${\beta}$-lactamase inhibitory effect of CGA and BRE while in silico docking showed that CGA bound strongly with the active sites of sulfhydryl-variable-1 ${\beta}$-lactamase. Furthermore, the mRNA transcript levels of two biofilm-associated genes (type 3 fimbriae mrkD and trehalose-6-phosphate hydrolase treC) were significantly downregulated in CGA- and BRE-treated samples. In addition, CGA inhibited biofilm formation by Escherichia coli and Candida albicans without affecting their planktonic cell growth. These findings show that BRE and its component CGA have potential use in antibiofilm strategies against persistent K. pneumoniae infections.

• 한국어류학회지
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• 제7권1호
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• pp.8-11
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• 1995

1986년(年) 5월(月) 제주도(濟州道)에서 채집(採集)한 통구멍과(科) 어류 중 체장(體長) 242.2 mm 되는 1개체(個體)를 동정한 결과(結果) 지금까지 우리나라에서는 서식(棲息)이 확인(確認)되지 않은 미기록종(未記錄種)인 Ichthyscopus lebeck sannio으로 동정(同定)되었다. 본 종은 외부(外部) 형태적(形態的)으로 등지느러미가 1개이고 입술에는 돌기가 발달되어 있고, 체표면에는 커다란 하얀 반점(斑點)이 많이 있으며 쇄골돌기가 없는 점 등이 본종(本種)의 주요(主要) 특징(特徵)으로 나타나고 있다. 본 종의 한국명(韓國名)은 체표면에 흰무늬가 크게 나 있는 것이 눈에 잘 띠기 때문에 "큰무늬통구멍속(屬)"의 "큰무늬통구멍"이라고 명명(命名)하였다.

• 한국가축번식학회지
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• 제8권1호
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• pp.10-15
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• 1984

This experiment was carried out to study the egg transports and distribution patterns in the oviducts of superovulated rabbits by administrations of PGF2$\alpha$. Group I (3 does) and Group II (3 does) were killed at 24 hours, 48 hours after mating, respectively. Group III (6 does0 received a single injection of 5mg/Kg of body weight of PGF2$\alpha$ at 24 hours after mating and killed at 4 hours after PGF2$\alpha$ administration. The oviducts were frozen in LN-gas, thawed using Howe's method, and cleared in Benzyl-Benzoate sol. using Orsini's technique. The location of the eggs and the AIJ. were identified using transmitted light from a dissecting microscope. The results obtained were as follows: 1. The average numbers of detected eggs from the oviduct were 28.6 (26-32), 26.0 (24-29), and 27.1 (22-34) in Group I, II, and III, respectively. 2. Detection rate was 88.7%, 76.4%, and 84.9% in Group I, II, and III, respectively. 3. The positionof all AIJ. was 44.2% to 55.0%(av. 49.5%) of the distance from the fimbriae to the UTJ.(Utero-Tubal Junction). 4. The changes of egg distribution patterns were as follows: Group I Ampulla : 52.3%, Isthmus : 47.7%, Group II Ampulla : 8.9%, Isthmus : 91.1% Group III Ampulla : 8.0% Isthmus : 92.0%.

• Clinical and Experimental Reproductive Medicine
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• 제20권1호
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• pp.95-98
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• 1993

Salpingoscopy may be helpful in the diagnosis of subclinical epithelial, vascular damage and stricture formation, which may playa significant role in infertility, or predispose women to tubal pregnancy, despite of clear demonstration of tubal patency on hysterosalpingogram. We explored the fallopian tube from the fimbriae to the ampullary-isthmic junction with small rigid flexible endoscope during laparoscopy in sixteen patients from July 1991 to Jan. 1992. All patients have been observed following salpingoscopy for several months. Three pregnancies were achieved in seven patients with bilaterally normal or minimally damaged tubal mucosa. In another five patients with moderate to severe tubal damage, we noted one tubal pregnancy. The other remaining patients are being followed up now. As conclusions, salpingoscopy seems to be an useful tool in the diagnosis of tubal lesions which are not identified by H.S.G., give much help to refine the indications for tubal microsurgery and the selection of patients for GIFT or IVF-ET and to determine the prognostic value in terms of risk for ectopic pregnancy.

• 대한수의학회지
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• 제57권1호
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• pp.9-15
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• 2017

To construct a novel vaccine candidate against bovine enterotoxigenic Escherichia coli (ETEC), FanC, the major subunit of K99 fimbriae adhesion, was inserted into secretion plasmid pYA3560 containing a ${\beta}-lactamase$ secretion system. This was then transformed into ${\Delta}asd$ ${\Delta}crp$ Salmonella (S.) Typhimurium and designated as JOL950. Secretion of recombinant fanC fimbrial antigens was confirmed by immunoblot analysis. Groups of mice were inoculated with single or double doses of JOL950. Another group was used as a negative control. Compared to control mice, all immunized mice had significantly higher levels (p < 0.05) of serum immunoglobulin (Ig)G, and secretory IgA against FanC. The IgG2a and IgG1 titer assays revealed that immunization highly induced IgG2a compared to that of IgG1, indicating that T helper-1- related cell-mediated immune responses may be elicited by JOL950. The results show that both systemic and mucosal immunities against selected fimbrial antigens of bovine ETEC expressed by a live attenuated S. Typhimurium strain are prominently produced in mice immunized with JOL950 via an oral route.