• 한국미생물·생명공학회지
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• 제27권2호
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• pp.136-144
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• 1999

Since the condition of immobilization must be optimized, it is very important to know whether and on how conditions bacterial cells retain their metabolic activity during immobilization process. A bioluminescence intensity had the maximum value when cell concentrations were between 1.0 and 1.2 measured at O.D660. The strontium alginate was used as an immobilization matrix and two independent factors for immobilization of Photobacterium phosphoreum with strontium alginate were optimized with the response surface methodology(RSM) considering degree of bioluminescence. As a result, the optimum concentration for immobilization was found to be 2.4%(w/w) for sodium alginate and 0.31M for strontium chloride, respectively. A dilution was carried out with 2.5%(w/v) NaCl solution that is an optimum environmental condition for growth of P. phosphoreum. Under the such condition of immobilization, hardness could be predicted as 4.66$\times$104N/$m^2$ and it took different time according to the volume of matrix to be immobilized completely.

• 대한화학회지
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• 제64권4호
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• pp.225-230
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• 2020

• 미생물학회지
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• 제49권2호
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• pp.205-210
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• 2013

루마진 단백질은 발광 세균인 Photobacterium 종에서 추출된 형광성 단백질이다. 형광성을 지닌 최소 크기의 Photobacterium leiognathi 야생형 아미노-말단 도메인 루마진 단백질(N-terminal domain of lumazine protein 118 wt)과 여러 영역에 tryptophan을 생성시킨 돌연변이 단백질들(N-LumP 118 V41W, S48W, T50W, D64W, A66W)을 코드하는 유전자들을 위치 지정 돌연변이(Site Directed Mutagenesis)와 중합효소 연쇄 반응(Polymerase Chain Reaction)을 통해 제조하였다. 위의 유전자들이 포함된 재조합 플라스미드를 대장균에 형질 전환시켜 과발현시키는 최적의 조건을 찾았으며, 발현된 야생형 및 돌연변이 아미노-말단 영역 루마진 단백질을 6X-His tag system을 이용하여 정제 하였다. 흡광 및 형광 분광광도계를 이용한 실험 결과 이들 단백질들은 리간드인 6,7-dimethyl-8-ribityllumazine과 결합하여 형광성을 보유함을 보였다. 따라서 이들은 형광성을 지니게 되는 최소 크기의 루마진 단백질일 뿐만 아니라 형광성을 지닌 아미노산인 tryptophan이 여러 위치에 유일하게 존재함으로써 배향성 및 거리 등의 단백질의 구조 및 결합에 관한 심도 있는 연구에 탐침자로써 유용하게 활용 될 수 있을 것이다.

• 한국임상수의학회지
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• 제27권5호
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• pp.618-621
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• 2010

서울 소재 수족관에서 관상용으로 사육되었던 giant grouper (Epinephelus lanceolatus) 한 마리가 폐사된 채발견되었다. 폐사어는 2주간 식욕부진, 무기력 및 침울의 증상을 보였다. 폐사어의 장기 (신장, 간 및 비장)로부터 세균을 순수 분리하여 Vitek System 2, API 20E test, multiplex PCR 및 16S rRNA gene sequencing을 수행하여 Photobacterium damselae subsp. damselae로 확진하였다. 본 증례에서, 우리는 국내 수족관에서 사육되었던 giant grouper에서의 Photobacterium damselae subsp. damselae의 분리 및 특성을 보고하고자 한다.

• KSBB Journal
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• 제14권1호
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• pp.91-95
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• 1999

P. phosphoreum의 고정화에 있어 중요한 것은 Matrix의 선택이며, Matrix로서 sodium algnate만을 사용하여 고정화하는 것보다는 strontnum chloride를 첨가하였을 때 세포의 bio-iummescence 유지도가 증가하였다. 저장 온도에 따른 bio-iummescence 유지도와 관련하여 -$70^{\circ}C,\;-20^{\circ}C,\;20^{\circ}C$에서 저장한 세포의 경우 저장 1일 후에 급격한 bioluminescence의 감소를 보였으나 $4^{\circ}C$ 에서 저장한 세포는 bioluminescence의 유지도가 15일 이상 이어졌다. 따라서 P. phosphoreum의 bioluminescence 안정성에 있어 가장 좋은 결과를 나타낸 것은 2.5%(W/W)sodium alginate와 0.3M(W/V)strontnum chloride 를 사용하여 고정화한 세포였으며 저장 온도는 $4^{\circ}C$였다.

• KSBB Journal
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• 제14권5호
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• pp.523-527
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• 1999

A naturally luminescent bacterium, Photobacterium phosphoreum was stored in 2.5% NaCl solution at 2$0^{\circ}C$, 4$^{\circ}C$, -2$0^{\circ}C$ and -7$0^{\circ}C$ for 30 days. In vivo luminescence and concentrations of total and culturable cells were determined by luminometer, spectrophotometer and dilution plate counting, respectively. When stored at 4$^{\circ}C$ and 2$0^{\circ}C$, concentrations of cells were rapidly decreased as a result of cell lysis, leading to adrop in turbidity and cultured counts. The bioluminescence of cells stored at 4$^{\circ}C$ was maintained until 12 days while those of cells starved at other temperatures decreased to background level within 3 days. Following incubation of stored cells in fresh liquid medium, activities of viable cells increased throughout storage period excepting cells stored at 2$0^{\circ}C$. Changes in bioluminescence intensity following addition of 2.5% NaCl solution markedly showed in cells stored at -2$0^{\circ}C$ and -7$0^{\circ}C$ and increased to maximum 8 fold.

• 한국미생물·생명공학회지
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• 제28권1호
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• pp.45-51
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• 2000

Photobacterium phosphoreum was used for the study of bioluminescence response to toxic substances including phenol, As2O3, SoO2, and CrO3 in view of developing monitoring system. measurement of inhibition of bioluminescence in P. phosphoreum has been proposed as a sensitive and raped procedure to monitor toxic substances. The concentration of toxic substance causing 50% light reduction(EC50) in bioluminescence intensity was determined with free and immobilized P. phosphoreum, The minimum inhibitory concentrations (MICs) for bioluminescence emission were found to be 400ppm for As2O3, 800ppm for phenol, 60ppm for SeO2 and 60ppm for CrO3 , respectively. The linear correlation between Gamma value and the concentration of toxic substances was obtained and EC50 wa calculated from the linear correlation. The free cells were shown to be more sensitive to toxic substances than cells immobilized on Sr-alginate and Ca-alginate. However, the linear regression curves were derived from the Sr-alginate immobilized cells indicating the immobilization method in s useful tool for monitoring of toxic substances under the more stable condition of bioluminescence.

• Biotechnology and Bioprocess Engineering:BBE
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• 제2권2호
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• pp.141-146
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• 1997

A new sensing system based on the immobilization of luminescent batcteria, Photobacterium phosphoreum, was proposed for continuous real-time monitoring of polluants. The response curves demonstrate that Photobacterium phosphoreum immobilized on the strontium alginate was very sensitive to seven reference chemicals used. The significant inhibitory concentrations for bioluminescence emission were 5 ppm for Pb(NO3)2, NiCl2, CdCl2, 50 ppm for NaAsO2, 0.1ppm for HgCl2, 0.5ppm for pentachlorophenol and less than 5ppm for SDS, respectively. The alginate mixed-cells (AMC) retained their luminescence during experimental period (29 days) under storage condition of -8$0^{\circ}C$. The variables affecting performance of continuous flow through monitoring (CFTM) were optimized in order to ensure stability and efficiency. The flow through cell with strontium-alginate immobilized luminescent bacteria was tested with salicylate and 4-nitrophenol and a rapid response of luminescence was recorded by time drive mode in bioluminescence spectrometer after exposure to both toxicants.

• 한국수산과학회지
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• 제49권6호
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• pp.838-844
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• 2016

In this study, epidemiological cut-off values were estimated for 44 Photobacterium damselae isolates, since clinical breakpoints have not been established for this pathogenic bacterium. The susceptibility of the isolates to 10 antibiotics was evaluated using internationally standardized disc diffusion protocols. Normalized resistance interpretation was used to generate statistically valid epidemiological cut-off values for the susceptibility data. There were not enough strains exhibiting full sensitivity to ampicillin and amoxicillin to allow analysis of these antibiotics. Because there were only a marginally sufficient number of strains exhibiting full sensitivity to oxytetracycline, the cut-off value generated provided only a provisional estimate. The valid wild-type cut-off values were <13, 13, 9, 22, 25, 27, and 28 mm for gentamicin, cephalexin, erythromycin, oxolinic acid, flumequine, florfenicol, and sulfamethoxazole/trimethoprim, respectively. The application of these cut-off values should greatly facilitate the rational selection of antibiotics for use in commercial fish farms.

• 미생물학회지
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• 제32권2호
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• pp.139-146
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• 1994

Photobacterium leiognathi CuZuSOD(PSOD)의 부세포성 분포에 따른 방어효과가 paraquat, 열 쇼크, 과산화수소 그리고 $CuSO_4$의 처리시 각각 조사되었다. 서로 달리 periplasm내에 분포하는 PSOD와 세포질에 분포하는 PSOD 사이의 생리적 특성은 본 연구에서는 조건에 따란 차이를 보였다. Paraquat나 $H_2O_2$ 처리시에는 periplasm에 SOD를 발현하는 세포에서 세포질내에 SOD를 분포하는 경우보다 약간 방호효과가 나았으며 SOD 발현 정도는 이와 일관되게 아주 중요한 변화를 보였다. 그러나 열 쇼크와 $CuSO_4$의 처리시는 각각 이런 현상이 역으로 나타났다.