• 한국수산과학회지
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• 제40권5호
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• pp.293-299
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• 2007

The distribution of hemolytic Vibrio sp. from sea water of three main beaches located in Busan (Gwangan(G), Haeundae(H) and Songjeong(S) beaches) was investigated from June to September 2006 ; this is mid-summer and the main season for bathing. The monthly detection ratio from each beach was 29.2% (7 of 24 samples, G), 33.3% (8 of 24 samples, H), and 16.7% (4 of 24 samples, S). The most probable number(MPN) of strains detected ranged from 1.8-36(G), 1.8-180(H) and 1.8-18(S) MPN/100mL. Of the isolated strains, 24 strains showed definite hemolytic activity. These 24 strains were identified as Vibrio fluvialis, Vibrio vulnificus, Aeromonas hydrophila, Actinobacillus ureae and Eikenella corrodens. Vibrio fluvialis was detected from all three beaches investigated. Vibrio vulnificus was detected from Haeundae and Gwangan beaches. Gwangan beach had a higher detection ratio of Vibrio sp. than Haeundae and Songjeong beaches. These results suggest that seafood harvested from the vicinity of theses beaches may cause food poisoning and risk management to prevent Vibrio septicemia is required, especially for Haeundae and Gwangan beaches.

• Fisheries and Aquatic Sciences
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• 제6권3호
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• pp.105-109
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• 2003

Fifty four strains of pathogenic vibrios were isolated from the Gwangan Beach from May to October, 2002. The isolated vibrios were composed of 7 different species: Vibrio parahaemolyticus, V. cholerae non-O1, V. alginolyticus, V. vulnificus, V. hollisae, V. fluvialis, ane V. mimicus. In the detection rate, V. parahaemolyticus was most predominant as $46\%$(25/54). From the isolated strains, only 25 strains have hemolytic activity or 25 strains only proteolytic activity on agar plates. Eleven strains showed both hemolytic and proteolytic activity. No strains showed urease activity. All strains of V parahaemolyticus did not show hemolytic activity, while V. cholerae non-O1 strains showed $\beta$ hemolytic activity. Kanagawa phenomena of pathogenic vibrios did not accord with hemolytic activity of the culture supernatant at the late log phase. Some strains showed high hemolytic activity despite having proteolytic activity, but some weak hemolytic activities despite having no proteolytic activity.

• Fisheries and Aquatic Sciences
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• 제5권3호
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• pp.178-182
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• 2002

The authors identified 68 Vibrio strains from Gwangan beach seawater from June to October in 2001. We identified them as 19 strains of Vibrio alginolyticus, 15 strains of V. vulnificus, 15 strains of V. parahaemolyticus, 11 strains of V. cholerae non O1, 7 strains of V. fluvialis and just one strain of V. hollisae. They showed their typical biochemical characteristics by API 20E kit (bioMerieux), respectively. It was examined whether their cultural supernatants had enzymatic activities such as hemolysin, protease or urease. The 46 strains showed hemolytic activities and/or protease activities. But we could not find any strain which had urease activity. All isolates of V. cholerae non O1 showed $\beta$ hemolysis. The others showed $\alpha$ hemolysis or did not show clear zones on sheep blood agar plates. These results of Kanagawa phenomenon were not always correspondant with hemolytic activities of cultural supernatants at late log phase. Some strains had higher hemolytic activities despite of showing protease activities on skim milk agar plates and in litmus milk media. On the other hand, some strains showed protease activities but did not show hemolytic activities. Therefore we could guess that there were the relationships between hemolysins and proteases produced by pathogenic vibrios.

• 한국식품영양과학회지
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• 제30권2호
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• pp.222-227
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• 2001

The members of the genus Vibrio include harmless aquatic strain as well as strains capable of causing infections in human and fish. Pathogenic mechanisms are only understood for Vibrio cholerae O1 and O139 and not for the majority of Vibrio species. Twelve clinical and nonclinical strains were examined by in vitro and in vivo experiments for the importance of extracellular enzymes as a virulence determinant of Vibrio species. In vivo cytotoxicity assay was performed by injecting approximately $10^{8}$ cells/mL into mice (BALB/c). V. harvyi and V. vulnificus showed 100% lethality within 3hr after bacterial injection. V. fluvialis and four strains of V. parahaemolyticus showed 50% lethality within 4hr. V. mimicus, V. alginolyticus and V. furnissii revealed 30% lethality within 9hr. Nonclinical strains, V. campbellii and V. ordalii, did not show any lethality. In vitro protease and hemolytic activities were also good indicators for clinical and nonclinical strains of Vibrio species. The clinical strains showed much higher activities than nonclinical strains. The activity of some clinical strains of re-isolates was evidently increased. Most clinical strains had $\beta$ hemolytic activity. The results demonstrate that the prevalent distribution of extracellular proteases in pathogenic Vibrio sp. implies their importance as a virulence determinant.

• Journal of Microbiology and Biotechnology
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• 제13권6호
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• pp.1021-1026
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• 2003

Numerous secreted and cell-associated virulence factors have been proposed to account for the fulminating and destructive nature of Vibrio vulnificus infections. Among the putative virulence factors are an elastase, elastolytic protease, and a cytolytic hemolysin. Effects of the elastase on the hemolysin were assessed by evaluating changes of hemolytic activities either in the presence or absence of the protease. Although hemolytic activity in the culture supernatant was lowered by the purified elastase added in vitro, the cellular level of hemolytic activity was unaffected by the mutation of vvpE encoding the elastase. Growth kinetic studies revealed that hemolysin reached its maximum level in the exponential phase of growth, and the elastase appeared at the onset of the stationary phase. These results have provided insight into the regulation of virulence factors: temporally coordinate regulation of virulence factors is essential for the overall success of the pathogen during pathogenesis.

• 한국식품위생안전성학회지
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• 제15권2호
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• pp.173-175
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• 2000

V. parahaemolyticus 종류들이 gelatin분해 확인 실험에서 큰 clear zone을 형성했고, V. alginolyticus 분리균주도 V. parahaemolyticus와 비슷한 clear zone을 형성했다. V. fluvialis KCTC 2473은 clear zone을 형성하지 못했다. Hemolytic activity측정 실험에서는 V. parahaemolyticus 분리균주(2)가 가장 활성이 크게 나타났고, V. parahaemolyticus ATCC 17802, V. parahaemolyticus 분리균주(1)과 V. mimicus ATCC 33653도 높은 활성을 나타냈으며, 나머지 다른 비브리오균은 활성이 나타나지 않았다. Azocasein분해 활성 실험에서는 V. parahaemolyticus ATCC 17802, 분리균주(1), 분리균주(2)는 200EU/m1전후로 활성이 높게 나타났고, 나머지는 110EU/ml전후로 활성이 상대적으로 낮게 나타났다.

• 한국수산과학회지
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• 제41권4호
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• pp.243-247
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• 2008

The hemolysin of Vibrio cholerae non-O1 CT isolated from sea water was purified and characterized. The purified hemolysin displayed an optimum at $37^{\circ}C$ and exhibited more than 70% of residual hemolytic activity after incubation at $45^{\circ}C$ for 120 min. However, the activity dropped dramatically at temperature above $55^{\circ}C$. The purified protein showed the highest hemolytic activity at pH 7.0, while the activity was completely lost outside of the pH ranges of 5.0 and 10.0. The activity of hemolysin was inactivated by addition of divalent cations, such as $Cu^{2+},\;Fe^{2+},\;Hg^{2+},\;Mn^{2+},\;and\;Zn^{2+}$, however, the activity was not completely inhibited by additions of $Ca^{2+},\;Mg^{2+},\;K^+,\;Na^+,\;and\;Li^+$.

• 한국수산과학회지
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• 제30권4호
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• pp.556-561
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• 1997

해수로부터 분리한 V. cholerae non-O1 FM-3 이 생산하는 hemolysin의 특성에 관하여 연구한 결과를 요약하면 다음과 같다. 1. V. cholerae non-O1 FM-3이 생산하는 hemolysin은 대수증식기일 때 가장 높은 활성을 나타내었으며, Sephadex G-100 gel column chromatography로 부분정제한 후 hemolysin의 특성을 실험한 결과, pH 7.0, $4^{\circ}C$에서 가장 안정하였으며, $60^{\circ}C$, 30분 가열에 의해 완전히 실활되었다. 2. 적혈구와 hemolysin이 반응할 때, $Na^+,\;K^+$과 같은 1가 양이온을 첨가하면 약간의 활성증가를 보였으며, $Ca^{2+},\;Mg^{2+},\;Mn^{2+}$과 같은 2가 양이온을 첨가하였을 때 급격한 활성증가를 보였고, 반면 $Zn^{2+}$ 첨가시에는 급격히 활성이 저하되었다. 3. 적혈구 현탁액과 hemolysin을 각각 다른 온도대에서 반응시킨 결과, $4^{\circ}C$에서도 온도와 관계없이 적혈구막과 hemolysin의 결합이 가능한 온도 비의존적인 제1단계와, 용혈황성의 최적온도대인 $37^{\circ}C$에서만 용혈작용이 일어나는 온도 의존적인 제2단계로 나누어졌다.

• 한국식품위생안전성학회지
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• 제12권1호
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• pp.9-14
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• 1997

Vibrio mimicus is a closely related species with V. cholerae, and has been reported to be associated with gastrointestinal infections. Although extraintestinal infections of these vibrios have also been reported in Japan and Southeast Asia. But little research papers on V. mimicus was reported in Korea. Therefore, we tried to isolate V. mimicus from the environmental sea water from April to July in Pusan, Korea. Among the isolated strains, we selected the strongest hemolytic strain and then named V. mimicus SM-9. In this paper, we checked the antibiotic susceptibility and psychrotrophic characteristics of the isolated strain. Hemolytic activity of the hemolysin produced by the isolated strain was also measured. V. mimicus was not detected from the sea water samples in April and May, but its detection rate was relatively high in June and July in Pusan, Korea. The bacteriological characteristics of V. mimicus SM-9 were Gram-negative rods, motile, oxidase positive, Voges-Proskauer negative and sucrose negative. In 23 kinds of antibiotics susceptibility test, V. mimicus SM-9 showed susceptibility to the most of antibiotics submitted while it was resistive against lincomycin, oxacillin, rifampin and vancomycin. Hemolytic activity of the hemolysin produced by V. mimicus SM-9 was highest in stationary phase of the growth curve in BHI broth at 37$^{\circ}C$ and its activity was reached 18 HU per $m\ell$ of culture supernatant. For checking the psychrotrophic property of V. mimicus SM-9, the decreasing rate of the strain in phosphate buffer solution and yellowtail flesh homogenate was examined during the storage at 4, 0, -4 and -2$0^{\circ}C$. The decreasing rates of the selected strain stored in phosphate buffer solution were greater than those in fish homogenate. Decreasing rates of V. mimicus SM-9 stored in phosphate buffer solution were not significantly different by the storage temperatures. The viable cell counts of the strain were decreased as 5 log cycles after 120 hours at all the tested temperatures. While decreasing numbers of the strain in fish homogenates were 2*4 log cycles after 120 hours. The decreasing pattern of the strain numbers were very slow after 200 hours at all the stored temperatures.

• 한국어병학회지
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• 제20권1호
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• pp.71-81
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• 2007

넙치, Paralichthys olivaceus 병어에서 분리된 Photobacterium damselae subsp. damselae와 Vibrio spp.(V. anguillarum, V. splendidus, V. harveyi and V. ordalii)의 병원성을 in vitro에서 조사하였다. Extracellular products (ECPs)의 성상은 효소 활성, 양과 넙치 적혈구에 대한 용혈능과 cell-line에 대한 세포 독성을 조사하였다. 그리고 세균의 internalization에서 signal transduction pathways를 signal transduction inhibitor를 이용하여 조사하였다.P. damselae는 phospholipase 활성, 넙치 적혈구에 대한 용혈능, 세포독성이 높게 나타났으며, 분리된 vibrios 균주에 비하여 internalization에서 다양한 경로를 나타내었다. 따라서 이러한 활성은 P. damselae의 병원성과 관련이 있을 것으로 생각된다.