• 한국미생물·생명공학회지
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• 제25권2호
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• pp.151-158
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• 1997

For the production of potent chitinolytic enzyme from bacteria, screening was carried out. Of 100 samples from soil, fresh water and sea water collected from the Kyung-gi area, 7 strains of chitinolytic bacteria were isolated. Among them, Aeromonas hydrophila 5-3K showed the highest chitinolytic activity. Culture conditions of Aeromonas hydrophila for the production of chitinolytic enzyme were inverstigated and lytic enzyme was fractionated by the use of ammonium sulfate and Sephadex G-100. Maximum production of chitinolytic enzyme was obtained at pH 7.0 and 30$\circ$C with chitin concentration between 0.2% and 1.0%. Conditions for the enzyme production were optimized including fermentor cultivation. The chitinolytic system of Aeromonas hydrophila 5-3K was composed of two enzymes, chitinase and chitobiase.

• 한국어병학회지
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• 제7권2호
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• pp.113-117
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• 1994

어병 세균에 대해 쑥(Artemisia princeps var. orientalis) 추출물인 정유의 항균성을 조사하였다. Aeromonas hydrophila, Aeromonas salmonicida, Aeromonas sorbia, Edwardsiella tarda 와 Streptococcus sp. (yellowtail)는 1,000~2,000 ppm 에서 증식이 억제되었다. 즉 억제 농도는 A.salmonicida 가 1,000 ppm A.hydrophila, A. sorbia, E. tarda 와 Streptococcus sp. (yellowtail)는 1,500 ppm 이었다. 그러나 Vibrio anguillarum, Vibrio ordalii, Edwardsiella ictaluri와 Streptococcus sp. (SF-1)는 100~2,000 ppm 농도에서 현저한 억제 효과는 없었다.

• 대한수의학회지
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• 제45권4호
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• pp.563-568
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• 2005

The present study was conducted to investigate biochemical characteristics and antimicrobial susceptibility of Aeromonas hydrophilia isolated from Jackass penguins (Spheniscus demersus) of zoo and capelins (Mallotus villosus). Seven of Jackass penguins showed anorexia, depression with seriously greenish vomiting for a few days, but resulted in 4 deaths although extensive treatment was carried out by zoo veterinarians. From the 18 samples composed of organs or feces from dead or live Jackass penguins and capelins, 4 (22.2%) Aeromonas hydrophilia were isolated and Bacillus spp, Staphylococcus aureus, Staphylococcus auricularis, Staphylococcus cohnii and Enterobacter aminigenus were also identified. Antimicrobial susceptibility tests of Aeromonas hydrophilia showed that all isolates were susceptible to amikacin, gentamicin, kanamycin, norfloxacin and trimethoprim- sulfadimethoxazole. However, all isolates were resistant to the following antimicrobials; ampicillin, bacitracin, c ephalothin, cefazolin, noboviocin, penicillin and vancomycin.

• 한국임상수의학회지
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• 제22권2호
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• pp.114-118
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• 2005

Bacterial disease caused by Aeromonas are among the most common and troublesome diseases of fish raised in aquaculture systems. In this study, some strains identified as belonging to the Aeromonas were isolated from neon tetra (Hyphessobrycon herbertaxelrodi) skin and fin, as well as from water samples. VITEK system and API ZYM examination of the isolated strains were undertaken, and it seemed to correlate with the Aeromonas, proved to be Aeromonas veronii. The antibiotic susceptibility test of isolated strains to different groups of antibiotics was evaluated using the disc diffusion method. Cefixime was the most sensitive antibiotic.

• 미생물학회지
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• 제43권2호
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• pp.106-110
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• 2007

USEPA 1605 방법을 이용하여 서울시 상수도계통에서 Aeromonas를 조사하였다. 2002년 7월부터 2003년 12월까지 매월 한강수계 하천수와 서울시 정수장에서 공급되는 정수, 수돗물에서 시료를 채취하였다. Aeromonas는 선택배지(ADA-V)를 사용하여 membrane 필터 표면에 성장한 노란색 집락을 계수하여 측정하였다. 하천수에서는 Aeromonas가 $1.0{\times}10^{0}-9.8{\times}10^{3}\;CFU/ml$의 농도로 검출되었으며, 정수에서는 검출되지 않았다. 수돗물에서는 141개 중 1개의 시료에서 1 CFU/500 ml의 농도로 검출되었다. 확인된 Aeromonas는 대부분 비병원성인 A. salmonicida(51%)였고, 이 외에도 A. caviae(4.7%), A. schubertti(3.4%), A. sobria(3.8%), A. hydrophila(2.1%), A ichithiosmia(0.4%)등이 동정되었다. A. salmonicida에 대한 염소 저항성을 평가한 결과, 0.2 mg/L 염소농도에서 30초 접촉 후, 99.99% (일부)가 제거되었다. USEPA 1605 방법에서 제시한 정도관리를 수행한 결과, 정도관리 허용기준을 만족하였다. 본 연구를 통해 서울시 상수도계통에서 Aeromonas에 대한 안전성이 확보되었다.

• KSBB Journal
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• 제31권4호
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• pp.228-236
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• 2016

The aim of this study was to characterize the hemolytic Aeromonas sp. MH-8 exposed to green tea catechin, epigallocatechin gallate (EGCG). Initially, the hemolytic Aeromonas sp. MH-8 was enriched and isolated from stale fish. Bactericidal effects of MH-8 exposed to EGCG ranging from 1 mg/mL to 4 mg/mL were monitored, and complete bactericidal effects were achieved within 3 h at 3 mg/mL and higher concentrations. SDS-PAGE with silver staining revealed that the amount of lipopolysaccharides increased or decreased in the strain MH-8 treated to different concentrations and exposing periods of EGCG in exponentially growing cultures. The stress shock proteins (70-kDa DnaK and 60-kDa GroEL), which might contribute to enhancing the cellular resistance to the cytotoxic effect of EGCG, were induced at different concentrations of EGCG exposed to cell culture of MH-8. Scanning electron microscopic analysis demonstrated the presence of irregular rod shapes with umbilicated surfaces for cells treated with EGCG. 2-DE of soluble protein fractions from MH-8 cultures showed 18 protein spots changed by EGCG exposure. These proteins involved in chaperons (e.g., DnaK, GroEL and trigger factor), enterotoxins (e.g., aerolysin and phospholipase C precursor), LPS synthesis (e.g., LPS biosynthesis protein and outer membrane protein A precursor), and various biosynthesis and energy metabolism were identified by peptide mass fingerprinting using MALDI-TOF. In consequence, EGCG was found to have substantial antibacterial effects against food-poisoning causing bacterium, hemolytic Aeromonas sp. MH-8. Also the results provide clues for understanding the mechanism of EGCG-induced stress and cytotoxicity on Aeromonas sp. MH-8.

• Applied Biological Chemistry
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• 제44권4호
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• pp.251-256
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• 2001

난용성 인산염을 가용화 시킬 수 있는 경제적이고 효율적인 생물비료를 개발하기 위하여 난용성 인산염 가용화능이 우수한 미생물을 염류 집적 및 인산과다처리 재배지로부터 분리하였다. 이 분리균주의 생리 생화학적인 특성을 조사한 결과 Aeromonas hydrophila DA57로 동정되었다. Aeromonas hydrophila DA57은 hydroxyapatite, tri-calcium phosphate 와 같은 난용성 인산염을 모두 가용화한다. 난용성 인산염의 분해능이 최대가 되는 배양 온도와 배양초기 pH는 각각 $30^{\circ}C$와 5.0이었으며, 탄소원으로 glucose를 3% 첨가시 가용화능이 높았다. 배양 pH가 감소함에 따라 가용화된 유리인산의 함량이 증가하였고 gluconic acid의 생성이 확인되었다. 따라서 난용성 인산염의 분해가 우수한 새로운 Aeromonas hydrophila DA57를 분리하였고, 이는 하나의 생물비료원으로 활용이 가능하리라고 사료된다.

• 대한화학회지
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• 제53권3호
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• pp.325-334
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• 2009

유기용매들에 대한 내성을 갖고 분해할 수 있는 능력을 가진 박테리아가 해수에서 단리되었지만, 해양조건에서 유기용매가 분해될 때 그들의 역할은 잘 알려져 있지 않았다. 콘스탄차 해수에서 단리된 Aeromonas hydrophila IB$B_{ct4}$는 여러 다른 종류의 유기용매들에 대하여 내성을 갖고 분해할 수 있는 능력을 가지고 있다. 옥탄올-헥산 혼합물에서 2.64 - 3.17 사이의 분배계수지수 (log $P_{ow}$)를 가진 톨루엔, 크실렌 이성질체들 및 에틸벤젠은, 3.69 - 4.39 사이의 log $P_{ow}$를 가진 프로필벤젠, n-헥산 및 n-헵탄보다 이들 박테리아에 더 독성이 있었다. Aeromonas hydrophila IB$B_{ct4}$에 유기용매들을 처리하였을 때 분자수준에서 세포의 변형이 유발되었다. 다른 유기용매들에 의하여 분자수준에서의 세포변화가 다르게 나타난다는 것을 밝힌 이 연구는 배양 조건에서 유기용매에 대한 박테리아 세포들의 반응이 복잡하다는 것을 보여 주고 있다.

• 한국수산과학회지
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• 제56권4호
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• pp.388-400
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• 2023

Aeromonas spp. and Pseudomonas spp. are opportunistic pathogens widely distributed in the aquatic environment. To test the antibiotic susceptibility, the MIC of the 18 antibiotics mainly used in aquaculture were measured. Aeromonas spp. and Pseudomonas spp. straoms had different resistance patterns against most antibiotics. The MIC of tetracycline for four Aeromonas spp. strains (10.5%) was < 0.25 ㎍/mL. However, 0.5-4 ㎍/mL tetracycline inhibited most Pseudomonas spp. strains. The tet resistance performance of 14 genes including tet(B), tet(E), and tet(M) were investigated. Investigating, the tetracycline resistance gene of 38 Aeromonas spp. strains detected tet(A) in 21 strains (55.3%). Two Pseudomonas spp. strains showed high MIC values and no inhibition zone. tet gene analysis detected tet(D) in only one strain (5%).

• 한국어병학회지
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• 제32권2호
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• pp.81-89
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• 2019

As an epidemiological survey, mortality of marbled rockfish, Sebastiscus tertius observed from a fish farm in Gyeongnam province of South Korea. The major macroscopic sign of the diseased fish was severe multifocal dermal ulceration. Histological observation revealed inflammation, necrosis and colonization of bacteria in various tissues (gill, liver, spleen and kidney). Bacteria was isolated from spleen and kidney in moribund and mortality fish. Seven bacterial isolates from the diseased fish were identified as Aeromonas salmonicida subsp. salmonicida using API 20E and 20NE, API 50CH API ZYM system. Under light microscopy, infected marbled rockfish showed the lifting of the lamella epidermal layer, edematous changes and hypertrophy of epithelial cell in the gill filament. The atrophy of the mucosal fold, erythema in the intestine, and the necrosis of hematopoietic tissue and renal tubule cells with karyolysis were observed in the kidney. In this study was demonstrated the histological reaction of red marbled rockfish infected by Aeromonas salmonicida. Furthermore, this is the first account of extensive dermatitis in Sebastiscus tertius due to atypical A. salmonicida infection, which has high potential in aquaculture among native fish species.