• Journal of Microbiology and Biotechnology
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• v.30 no.7
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• pp.1037-1043
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• 2020

Actinobacillus pleuropneumoniae (APP) is a causative agent of porcine pleuropneumonia. Therefore, the development of an effective vaccine for APP is necessary. Here, we optimized the culture medium and conditions to enhance the production yields of Apx toxins in APP serotype 1, 2, and 5 cultures. The use of Mycoplasma Broth Base (PPLO) medium improved both the quantity and quality of the harvested Apx toxins compared with Columbia Broth medium. Calcium chloride (CaCl₂) was first demonstrated as a stimulation factor for the production of Apx toxins in APP serotype 2 cultures. Cultivation of APP serotype 2 in PPLO medium supplemented with 10 ㎍/ml of nicotinamide adenine dinucleotide (NAD) and 20 mM CaCl₂ yielded the highest levels of Apx toxins. These findings suggest that the optimization of the culture medium and conditions increases the concentration of Apx toxins in the supernatants of APP serotype 1, 2, and 5 cultures and may be applied for the development of vaccines against APP infection.

• Korean Journal of Pharmacognosy
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• v.30 no.3
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• pp.244-249
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• 1999

In order to find less toxic antiviral agents from Basidiomycetes, EA, the water soluble substance, was prepared from the carpophores of Elfvingia applanata(Pers.) Karst. Antiviral activity of EA against vesicular stomatitis virus [Indiana serotype, VSV(IND)] was examined in Vero cells using plaque reduction assay in vitro. And the combined antiviral effects of EA with interferon (IFN) alpha or gamma were examined on the multiplication of VSV(IND). EA caused a concentration-dependent reduction in the plaque formation of VSV(IND) with 50% effective concentration $(EC_{50})$ of $104.02\;{\mu}g/ml$. The results of combination assay were evaluated by the combination index (CI) that was analysed by the multiple drug effect analysis. All cases of the combination of EA with IFN alpha or IFN gamma showed potent synergism with CI values of $0.38{\sim}0.52$ for $50{\sim}90%$ effective levels.

• Korean Journal of Veterinary Research
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• v.27 no.2
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• pp.223-226
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• 1987

Serological classification was carried out on 10 samples of PEV isolated from the feces, the milk and the brain of the diseased pigs in Korea by CFT using type specific antisera of PEV. Ten samples of PEV were classified into 2 serotypes which were serotype 3 and 8. PEV from the feces belonged to serotype 8 and those from the milk and the brain to serotype 3. The cross reaction of serotype 3 occurred especially with serotype 1. Talfan virus. It can be said that at least 2 serotypes of PEV have existed in Korea.

• The Korean Journal of Mycology
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• v.27 no.2 s.89
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• pp.175-179
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• 1999

In order to find less toxic antiviral agents from Basidiomycetes, EA, the water soluble substance, was prepared from the carpophores of Elfvingia applanata (Pers.) Karst. Antiviral activity of EA against vesicular stomatitis virus [New Jersey serotype, VSV(NJ)] was examined in Vero cells using plaque reduction assay in vitro. And the combined antiviral effects of EA with interferon (IFN) alpha and gamma were examined on the multiplication of VSV(NJ). EA caused a concentration-dependent reduction in the plaque formation of VSV(NJ) with 50% effective concentration $(EC_{50})$ of 2.10 mg/ml. The results of combination assay were evaluated by the combination index (CI) that was analysed by the multiple drug effect analysis. The combination of EA with IFN alpha showed more potent effect with CI values of $0.87{\sim}1.59$ for 50%, 70% and 90% effective levels than that with INF gamma with CI values of $1.05{\sim}2.03$.

• Korean Journal of Veterinary Service
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• v.32 no.4
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• pp.315-323
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• 2009

Foot-and-mouth disease (FMD) virus exists in seven serotypes and is known to be a highly contagious disease that is hard to eradicate from the world. The O, A, Asia1 and SAT2 serotypes commonly infected cattle, sheep and goats during 2007~2009 throughout the world. In particular, the outbreak of the Asia1 serotype in China appeared in all areas from 2005 and is still present. Surprisingly, in 2009, Taiwan reported the first outbreak of the type O serotype since 2001. Then type A appeared in China for the first time since the early 1960s. The virus shows a close relationship to the viruses from Southeast Asia suggesting one or more recent introductions into China in the OIE reports. Recently the subtype of A/Iran05 spread to nearby countries exhibiting genomic evolution. The use of molecular epidemiology is an important tool in understanding and consequently controlling the FMD virus. The phylogenetic analysis with VP1 gene was especially useful for molecular epidemiological studies and showed the same pattern which matches with serotype classification. This paper describes basic information about the disease, and the serotype-specific characteristics and evolution to perform molecular epidemiological analysis. Furthermore, we show the importance of the genetic evolution on the FMD serotypes in global surveillance and molecular epidemiology of FMD for outbreak investigation.

• Korean Journal of Microbiology
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• v.43 no.4
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• pp.346-350
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• 2007

We analyzed the phenotypic changes in coagulase serotype of S. aureus isolated from clinical sources and nasal cavities of healthy persons, $1994{\sim}2005$. A total of 715 isolates, 408 methicillin resistant S. aureus (MRSA) from clinical sources and 307 methicillin-susceptible S. aureus (MSSA), were classified into eight coagulase sero-types, I to VIII. The most prevalent serotype in MRSA was type II (54.3%, 222/408) and followed IV (24.7%), III (10.9%), and V (5.2%), whereas the majorities in MSSA were type VII (30.9%, 95/307), IV (22.2%), V (22.2%) and II (7.1%). Among the isolates collected periods, significant changes of coagulase serotypes in both strains were observed. In MRSA strains, the serotype V was not detected until 1997, but rapidly increased to 18.5% (20/108) in 2005, and the serotypes III decreased from 27% (31/115) in 1994 to 0.9% (1/108) in 2005. A similar trend in MSSA strains was observed but serotype II strain was not detected in 2005. The antigenic shift and changes in the coagulase of S. aureus were confirmed.

• The Journal of the Korean Society for Microbiology
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• v.19 no.1
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• pp.65-71
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• 1984

The author attempted serological typing with the slide agglutination and the production of heat-labile enterotoxin (LT) and heat-stable enterotoxin (ST) by the enterotoxingenic eschenchia coli 446 strains isolated from diarrheal patients. The enterotoxingenic E.coli, producing LT and/or St, were detected by use of assays in the reversed passive hemagglutination(RPHA) and the suckling mouse method. The results obstained were as follows: 1. Of 446 strains isolated, 88 strains(19.73%) produced LT, while 224 strains(50.22%) produced ST, 134(30.05%) produced both LT-ST simultaneously. Serological typing were typed into 06, 08, 020, 025, 027, 0126, 0148 and 0159. Serotype 06 had the highest incidence of 26.46% followed by 0148(18.16%), 027(14.57%); 025(10.99%), 0159(4.03%), 0126(3.59%), 020(1.12%) and 08(0.45%). 2. Serotype 06, 08 and 025 almost always produced both LT and ST, whereas serotypes 020, 027 and 0148 almost always produced only ST. And serotypes 06, 025, 0126 and 0159 almost always produced LT or ST. 3. Of 134 LT-ST positive strains, 115 strains were serotype 06, 3 strains were 025, 2 strains were 08, and 14 strains were 0 untypable. 4. Of 224 ST positive strains, 65 strains were serotype 027, 81 strains were 0148, 16 strains were 0159, and 42 strains were 0 untypable. 5. Of 88 LT positive strains, 45 strains were serotype 025, 5 strains were 0126, 2 strains were 0159, and 42 strains were 0 untypable.

• Journal of Periodontal and Implant Science
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• v.25 no.1
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• pp.153-166
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• 1995

54 clinical isolates of Actinobacillus actinomycetemcomitans showed distinct hybrdization patern(DAN fingerprinting patterns) when the bacterial DNA were hybridized with randomly cloned 4.7 - kb DNA probe. The frequency of the genotypic distribution demonstrated that type C was the most prevalent genotype, the next being D, NT, A, B, and E in the descending order. The most prevalent serotype was serotype c, the next being a, nd, and b in the descending order. It was noted that the one serotype can represent more than two different genotypes and that multiple genotypic variants can also exist in the periodontal pockets within the sam subject.

• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.359-363
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• 1999

To prevent appearance of resistant mosquitoes against $\delta$-endotoxin of bacillus thuringiensis subsp. israelensis (Bti) in field, a mosquitocidal Bacillus thuringiensis strain 21-2(Bt21-2) producing a new type of $\delta$-endotoxin was isolated. The strain Bt 21-2 belongs to H serotype 43, B. thuringiensis subsp. guiyangiensis (Btg). The $\delta$-endotoxins from the strain Bt 21-2 and the strain Bti were a cuboid shape morphologically, but the $\delta$-endotoxin of the strain Bt 21-2 was composed of 150, 90 and 70kDa proteins on SDS-PAGE, and the antigenicity of $\delta$-endotoxin of the strain Bt 21-2 was different from that of the strain Bti on immunoblot. The $\delta$-endotoxin gene of the strain Bt 21-2 was not amplified with specific primers of $\delta$-endotoxin gene (cry4A and cry4B) of the strain Bti on PCR.

• Journal of Periodontal and Implant Science
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• v.26 no.2
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• pp.365-375
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• 1996

5 serotypes(a, b, c, d, e) of Actinobacillus actinomycetemcomitans showed distinct hybridization patterns(DNA fingerprinting patterns) when the bacterial DNA were hybridized with randomly cloned 4.7-Kb sized DNA probe. The sizes of hybridized bands in each serotypes were different among serotypes and represented unique patterns of hybridization with the probe used. The serotype a showed two bands of fingerprinting patterns: 23.1 kb and 2.5 kb respectively. Serotype b and c showed single band: 6.6 kb and 9.5 kb, respectively. Serotype d and e showed two bands of hybridization: 23.1 kb and 2.8 kb, and 23.7 kb and 2.1 kb, respectively. The results indicate that this standard fingerpriting patterns of DNA hybridization with 4.7 kb probe can be further used for genotyping clinical isolates of Actinobacillus 8ctinomycetemcomitansand its relevance with periodontal disease activity.