• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.117-120
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• 2000

For detecting toxicity of endocrine disruptors (EDs), rapid, sensitive, and simple methods are needed. Therefore, in this study, a new method in which the different toxic effect of EDs can be monitored using 4 different recombinant bacteria was designed and evaluated. It was found that the recombinant bacteria could monitor the toxic effect, not estrogenic effect, due to EDCs through the measurement of bioluminescence and cell growth rate, which were shown to depend upon a form of cellular toxicity, such as DNA damage, protein damage, oxidative damage, and membrane damage. In addition, it was found that the damage done by EDCs can be divided into several groups based upon the toxic mechanisms of the EDCs

• Korean Journal of Veterinary Research
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• v.29 no.3
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• pp.393-405
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• 1989

This study was carried out to treatment test for bovine mastitis by the determination of adenosine triphosphate (ATP) based on firefly bioluminescence. The results obtained are followed; 1. In the susceptibility test, cephalothin which looks the most effective were sensitive to Staphylococcus sp. (72.3%), Micrococcus sp. (84.2%), Streptococcus sp. (72.7%) and Gram positive bacilli (72.7%), Gram negative bacilli were sensitive to gentamicin (92.3%) and Yeast-like-fungi was the most sensitive to clotrimazole, and nystatin in order. 2. When the number of bacteria, such as Staphylococcus aureus, Candida tropicalis isolated from the mastitis milk were counted by conventional agar plating technique, and compared with the concentration of bacterial ATP, it gave a good linear relationship. The content of ATP per Staphylococcus aureus, cell was 3.1fM and Candida tropicalis showed the high level of A TP (90fM). 3. The ATP assay was applied to the determination of minimal inhibitory concentration (MIC) of various antibiotics. When Staphylococcus aureus was incubated in the presence of different concentration of tetracycline, erythromycin, kanamycin and streptomycin sulfate and the growth was monitored by the conventional agar plating technique and ATP assay, both methods shown the same results that they were 1mcg/ml, 2mcg/ml, 6.25mcg/ml and 8mcg/ml, respectively. 4. For the determination of susceptibility of sensitive and resistant Staphylococcus au reus isolated for the milk with mastitis to tetracycline, erythromycin kanamycin and streptomycin sulfate, the minimum time required for the test was determined by the assay of ATP every 30 minutes during incubation of 3 hours at $37^{\circ}C$. ATP concentration time curve calculated on both resistant and sensitive strains incubated 3 hours as the optimum time for the determination of susceptibilities of various antibiotics exemed. The ATP concentration of each test broth (antibiotic containing), expressed as a percentage of its own control brith (antibioticfree) indicated values of 30% to be indicative of each antibiotic sensitivity. Single time point ATP assay carried out on the various sensitive and resistant of Staphylococcus aureus to antibiotics examined after 3 hours at $37^{\circ}C$ correlated exactly with disc diffusion and MIC. 5. In the cure of intramammary treatment of bovine mastitis in lactating quarters, the cure rate of Staphylococcal mastitis showed to cephalexin (80%), cloxacillin and gentamicin (70%), ampicillin and oxytetracycline (60%), and Streptococcal mastitis showed to cephalexin (85%), penicillin (80%), cloxacillin and oxytetracycline (75%), and ampicillin (70%), but intramammary antimycotic drug (clotrimazol) were only a little effect about fungal mastitis.

• Ocean Science Journal
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• v.40 no.2
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• pp.91-100
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• 2005

Bioassay using the marine bacteria, Vibrio fischeri and rotifer, Brachionus plicatilis, and chemical analyses were conducted to assess the toxicity of the various sewage sludges, one of the major ocean dumped materials in the Yellow Sea of Korea. Sludge elutriates extracted by filtered seawater were used to estimate the ecotoxicity of the sludge. Chemical characterization included the analyses of organic contents, heavy metals, and persistent organic pollutants in sludge. Bacterial bioluminescent inhibition (15 min), rotifer mortality (24 hr) and rotifer population growth inhibition (48 hr) assay were conducted to estimate the sludge toxicity. EC50 15 min (inhibition concentration of bioluminescence after 15 minutes exposed) values by Microtox(R) bioassay clearly revealed different toxicity levels depending on the sludge sources. Highest toxicity for the bacteria was found with the sludge extract from dyeing waste and followed by industrial waste, livestock waste, and leather processing waste. Clear toxic effects on the bacteria were not found in the sludge extract from filtration bed sludge and rural sewage sludge. Consistent with Microtox(R) results, rotifer neonate mortality and population growth inhibition test also showed highest toxicity in dyeing waste and low in filtration bed and rural sewage sludge. High concentrations of persistent organic pollutants (POPs) and heavy metals were measured in the samples from the industrial wastes, leather processing plant waste sludge, and urban sewage sludge. However, there was no significant correlation between pollutant concentration levels and the toxicity values of the sludge. This suggests that the ecotoxicity in addition to the chemical analyses of various sludge samples must be estimated before release of potential harmful waste in the natural environment as part of an ecological risk assessment.

• Proceedings of the Microbiological Society of Korea Conference
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• 2008.05a
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• pp.135-135
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• 2008

Various biosensors were evaluated for identifying and detecting foodborne pathogens in a rapid and effective manner. First, five strains of Escherichia coli and six strains of Salmonella were identified using Fourier transform infrared spectroscopy and a statistical program. For doing this, lipopolysaccharides (LPSs) and outer membrane proteins (OMPs) were extracted from a cell wall of each bacterial strain. As a result, each strain was identifed at the level of 97% for E. coli and 100% for Salmonella. Second, E. coli O157:H7, S. Enteritidis, and Listeria monocytogenes were identified by multiplex PCR products from four specific genes of each bacteria using a capillary electrophoresis (CE). Also, ground beef for E. coli O157:H7, lettuce for S. Enteritidis, and hot dog for L. monocytogenes were used to determine the possibility of detecting pathogens in foods. Foods inoculated with respective pathogen were cultivated for six hours and multiplex PCR products were obtained and assessed. The minimum detection levels of tested bacteria were <10 cells/g, <10 cells/g, and $10^4$ cells/g for E. coli O157:H7, S. Enteritidis, and L. monocytogenes, respectively. Third, it was possible to detect S. Typhimurium in a pure culture and lettuce by a bioluminescence-based detection assay using both recombinant bacteriophage P22::luxI and a bioluminescent bioreporter. In addition, bacteriophage T4 was quantitatively monitored using E. coli including luxCDABE genes.

• Korean Journal of Microbiology
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• v.52 no.4
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• pp.495-499
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• 2016

In order to identify the biochemical characteristics of LuxG, the luxG gene from bioluminescence bacteria of Photobacterium leiognathi ATCC 25521 was isolated by PCR-Amplification and inserted into pQE30 vector containing the T5 promoter and 6X His-tag system. The resulting recombinant plasmid was transformed into Escherichia coli to over-express the luxG gene and purify the gene product. The purified LuxG protein demonstrated ferric iron reductase activity and the kinetic parameters of $K_m$ and $V_{max}$ for FMN as well as the NADPH substrates of ferric iron reductase were determined, respectively.

• Korean Journal of Microbiology
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• v.36 no.1
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• pp.74-78
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• 2000

Vibrio, Photobacterium, Alteromonas and Xenorhabdus species are capable of emitting light, called bioluminescence. They exist in marine, freshwater and terrestrial environments. Bacterial bioluminescent reaction is that reduced riboflavin phosphates and a long-chain aldehyde are oxidized in the presence of molecular oxygen and enzyme luciferase. This experiment aims to develop the proper culture media and to optimize the storage condition for the recovery of bioluminescent activity in Photobacterium phosphoreum. The Luria broth (LB) medium was modified for cultivation of Photobacterium phophoreum, called as modified LB(mLB) medium. The mLB medium is LB fortified with 3% glycerol and 1.5% NaCl. In mLB medium. bacterial growth and bioluminescent activity are 25% higher than those in a Nutrient broth medium. When the cell stocks were stored at $-20^{\circ}C$, $-70^{\circ}C$ and LN2 for 3 months, cell growth and bioluminescent activity of culture after stored at $-20^{\circ}C$ were better than those of other treatments. The highest bioluminescent activity obtained at the late exponential phase in all treatments. When the cell stock was freeze-dried with 5% adonitol as a cryoprotectant, the recovery of cell was better than those of control and freeze-dried cell stock without addition of cryoprotectant.

• The Journal of Advanced Prosthodontics
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• v.12 no.4
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• pp.233-238
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• 2020

PURPOSE. This study aims to compare the marginal fitness of two types of implant-supported fixed dental prosthesis, i.e., cementless fixation (CL.F) system and cement-retained type. MATERIALS AND METHODS. In each group, ten specimens were assessed. Each specimen comprised implant lab analog, titanium abutment fabricated with a 2-degree tapered axial wall, and zirconia crown. The crown of the CL.F system was retained by frictional force between abutment and relined composite resin. In the cement-retained type, zinc oxide eugenol cement was used to set crown and abutment. All specimens were sterilized with ethylene oxide, immersed in Prevotella intermedia culture in a 50 mL tube, and incubated with rotation. After 48 h, the specimens were washed thoroughly before separating the crown and abutment. The bacteria that penetrated into the crown-abutment interface were collected by washing with 500 µL of sterile saline. The bacterial cell number was quantified using the agar plate count technique. The BacTiter-Glo Microbial Cell Viability Assay Kit was used to measure bacterial adenosine triphosphate (ATP)-bioluminescence, which reflects the bacterial viability. The t-test was performed, and the significance level was set at 5%. RESULTS. The number of penetrating bacterial cells assessed by colony-forming units was approximately 33% lower in the CL.F system than in the cement-retained type (P<.05). ATP-bioluminescence was approximately 41% lower in the CL.F system than in the cement-retained type (P<.05). CONCLUSION. The CL.F system is more resistant to bacterial penetration into the abutment-crown interface than the cement-retained type, thereby indicating a precise marginal fit.

• Food Science of Animal Resources
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• v.37 no.1
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• pp.147-152
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• 2017

A bioluminescent Lactobacillus plantarum (pLuc2) strain was constructed. The luminescent signal started to increase during the early exponential phase and reached its maximum in the mid-exponential phase in a batch culture of the strain. The signal detection sensitivity of the strain was the highest in PBS (phosphate buffered saline), followed by milk and MRS broth, indicating that the sensitivity was influenced by the matrix effect. The strain was used in millet seed fermentation which has a complex matrix and native lactic acid bacteria (LAB). The luminescent signal was gradually increased until 9 h during fermentation and abolished at 24 h, indicating that the strain could be specifically tracked in the complex matrix and microflora. Therefore, the bioluminescent labeling system can be used for monitoring LAB in food and dairy sciences and industries.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.6
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• pp.516-521
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• 2006

The use of gltA gene, as a new biomarker for environmental stress biomonitoring, was investigated because of its key position as the first enzyme of the tricarboxylic acid (TCA) cycle. A recombinant bioluminescent Escherichia coli strain, EBJM2, was constructed using a plasmid carrying the citrate synthase (gltA) promoter transcribing the Photorhabdus luminescens IuxCDABE genes (gltA::luxCDABE). The responses from this strain were studied with five different classes of toxicants: DNA damage chemicals, phenolics, oxidative-stress chemicals, PAHs, and organic solvents. EBJM2 responded strongly to DNA damage chemicals, such as mitomycin C (MMC) and methyl-nitro-nitrosoguanidine (MNNG) and nalidixic acid with the strongest responses. In contrast, tests with several compounds from the other four classes of toxicants gave no significant response. Therefore, EBJM2 was found to be sensitive to DNA damage chemicals.

• Journal of Marine Life Science
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• v.7 no.2
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• pp.74-85
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• 2022

Organisms constituting a large proportion of marine ecosystems, ranging from bacteria to fish, exhibit fluorescence and bioluminescence. A variety of marine organisms utilize these biochemically generated light sources for feeding, reproduction, communication, and defense. Since the discovery of green fluorescent protein and the luciferin-luciferase system more than a century ago, numerous studies have been conducted to characterize their function and regulatory mechanism. The unique properties of fluorescent and bioluminescent proteins offer great potential for their use in a broad range of applications. This short review briefly describes the functions and characteristics of fluorescent and bioluminescent proteins, in addition to summarizing the recent status of their applications.