• Title/Summary/Keyword: Bioluminescence

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Conditions for Stable light Production of Recombinant Escherichia coli Containing Lux Operon and Sensitivity to Toxic Chemicals (Lux operon을 함유한 유전자 재조합 Escherichia coli의 발광 안정화 조건 및 독성물질에 대한 민감성)

  • 배희경;이상민;정윤철;송방호;신평균
    • KSBB Journal
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    • v.17 no.6
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    • pp.571-576
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    • 2002
  • Recombinant E. coli DH5 ${\alpha}$/pSB311 was made by cloning the genes encoding bacterial luciferase and aldehyde substrate proteins from Photohabdus luminescense, to complement defects of Lumistox, which is normally used in bioassays to monitor toxic substances in water environmental systems. The conditions for stable light production by the recombinant strains were investigated with respect to cell growth stage, cell number, and buffer conditions. The optimum growth stage was a middle-exponential stage with an OD$_{660nm}$ value of 0.6-0.7. ADout 10$^{6}$-10$^{7}$ cells per test tube was optimum for stable light emission. The effect of buffer was not significant if an optimum viable cell number was maintained. The bioluminescence of the recombinant E. coli harboring the lux operon of Photohabdus luminescense was not affected by temperature, while the bioluminescence of Lumistox was temperature sensitive. The recombinant E. coli was more sensitive to heavy metals (Cd, Cu, Hg, Zn) than Lumistox, because it does not require high concentrations of NaCl in the buffer.

Optimum Conditions of Freezing Lyophilization and Bioluminescence Activity Recovery for Environmental Applications Using a Recombinant Strain (유전자 재조합 균주를 환경에 적용하기 위한 (동결) 건조 및 활성회복 조건 최적화)

  • Ko Kyung-Seok;Kim Myung-Hee;Kong In-Chul
    • Journal of Soil and Groundwater Environment
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    • v.11 no.5
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    • pp.43-50
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    • 2006
  • Bioreporter bacteria, such as recombinant bioluminescent bacteria, have been used for the detection of specific compounds in complex environmental media. In this study, optimum conditions for the preparation and application of deep-freezed and Iyophilized recombinant bioluminescent strain KG1206 were investigated for the future application on contaminated environmental sites. Genetically engineered microorganism, Pseudomonas putida mt-2 KG1206, contains TOL plasmid and the plasmid inserted $P_{m}$, promoter on the upper part of lux gone in vector pUCD615, and m-toluate and benzoate are considered direct inducers for bioluminescence. Optimum conditions determined for the preparation and application of the deep-freezed and lyophilized strain were followings: cryoprotective agent (24% sucrose), lyophilization time (12 hrs), strain concentration ($OD_{600}=0.6$), reconstitution for freezed strain (quick reconstitution at $35^{\circ}C$), reconstitution for lyophilized strain ($3{\sim}6$ hrs exposure on LB medium), carrying conditions (keep at $20^{\circ}C$ after reconstitution). These results demonstrate the feasibility of deep-freezed or lyophilized state of genetically engineered bioluminescent strain for environmental usage.

Quorum Sensing Regulation of Biofilm Formation by Periodontal Pathogens

  • Choi, Bong-Kyu
    • International Journal of Oral Biology
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    • v.43 no.4
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    • pp.171-175
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    • 2018
  • Quorum sensing (QS) is a cell density-dependent communication mechanism between bacteria through small signaling molecules. When the number of QS signaling molecules reaches a threshold, they are transported back into the cells or recognized by membrane-bound receptors, triggering gene expression which affects various phenotypes including bioluminescence, virulence, adhesion, and biofilm formation. These phenotypes are beneficial for bacterial survival in harsh environments. This review summarizes the application of QS inhibitors for control of biofilm formation and virulence expression of periodontal pathogens.

AHL inhibition of Beckerelide and Fimbrolide

  • Kim, Yeon-Hee;Lee, Jae-Gun;Park, Sung-Hoon;Kim, Jung-Sun
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.174.2-174.2
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    • 2003
  • Quorum sensing, a gene expression in response to population density, is regulated by chemical signals, most of which are acylated homoserine lactones (AHLs). The AHL derivatives have been reported to regulate bioluminescence, virulence factors and / or swarming motility in bacteria. It is hypothesized that higher organisms may have evolved specific means to interfere with bacterial communication as exemplified in the AHL-antagonistic activity of halogenated furanones isolated from the Australian macroalga Delisea pulchra. (omitted)

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Ferric iron reductase activity of LuxG from Photobacterium leiognathi (Photobacterium leiognathi LuxG 단백질의 철(III) 이온 환원 효소 활성도)

  • Lee, Eui Ho;Nam, Ki Seok;Lee, Seon Kwang;Oh, Eugeney;Lee, Chan Yong
    • 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.

A Study on Gamma ray effects on Stress Response and Cellular Toxicity using Bacterial Cells

  • Min, Ji-Ho;Lee, Hyeon-Ju;Lee, Chang-U;Gu, Man-Bok
    • 한국생물공학회:학술대회논문집
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    • 2000.11a
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    • pp.187-190
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    • 2000
  • Effects of gamma ionizing radiation on recombinant Escherichia coli cells containing stress promoters, recA, fabA, grpE, or katG, fused to luxCDABE originated from Vibrio fischeri were characterized by monitoring transcriptional responses reflected by bioluminescent output. Quantification of gamma-ray intensity may be possible using the recA and fabA promoter fusion since a linear enhancement of bioluminescence emission with increasing gamma-ray intensity was observed. Other strains sensitive to either oxidative stress (DPD2511, katG::luxCDABE) or protein-damaging stress (TV1061, grpE::luxCDABE) were also irradiated by gamma-rays, and resulted in no noticeable bioluminescent output while DPD2794 with recA promoter and DPD2540 with fabA promoter irradiated by the same intensities of gamma-rays gave a significant bioluminescent output. This indicates that the main stresses in the recombinant bacteria caused by ionizing radiation are DNA and membrane-damage, not protein- or oxidative-damage. In addition, in this study, to investigate the relationship between the radiation dose rate and bacterial responses, two recombinant Escherichia coli strains, DPD2794 and GC2, containing lac promoter fused to luxCDABE originating from Photorhapdus luminescences, were used for detecting DNA damage and cellular toxicity under various radiation dose rates. Throughout this study, it was found that these bacteria showed quantitative stress responses to DNA damage and general toxicity caused by gamma rays, depending on the radiation dose rates, indicating that the bacterial stress responses and general toxicity were seriously influenced according to radiation dose rates.

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Setting Guidelines for ATP Bioluminescence Hygiene Monitoring of Distribution Trays in Used Children's Foodservices (어린이 급식소의 배식용기 표면에 대한 ATP(Adenosine Triphosphate) 위생 모니터링 가이드라인 설정)

  • Moon, Hye-Kyung
    • Journal of the Korean Dietetic Association
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    • v.26 no.4
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    • pp.243-253
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    • 2020
  • The purpose of this study was to set new guidelines for adenosine triphosphate (ATP) bioluminescence hygiene monitoring of distribution trays at children's foodservices. Five dietitians visited 223 foodservices (95 institutional, 128 small) to examine whether they adhered to the norms of 'Keeping distribution tray sanitary by washing/sanitizing' and 'Performing food distribution in a clean and appropriate way'. In this visit, dietitians swabbed 100 ㎠ area of the distribution trays twice, once for obtaining ATP measurements and the second time for Aerobic Plate Counts (APC) using 3M Petrifilm Plates. Chi-square test and ANOVA were applied using SPSS 23.0 software. SPSS 23.0 was used to conduct graphical and statistical analysis of the raw data of ATP measurements, which were further transformed by a Box-Cox transformation. The mean of APC from all the subjects inspected was 3.8×102±2,102.0 CFU/100 ㎠. A total of 208 (93.3%) trays were observed within the acceptable limits of APC (Pass<5.0×102 CFU/100 ㎠). APCs taken at institutional foodservices showed significantly lower levels (1.4×102±600.0 CFU/100 ㎠, P<0.01) compared to the small foodservices (5.5×102±2,718.7 CFU/100 ㎠). No significant differences were observed between the two groups in ATP measurements and in the performance rate of 2 checklist items. As against the 93.3% APC adequacy from the total subjected inspection, total ATP adequacy (Pass≤300 RLU/100 ㎠) was only 71.7%. Therefore, more practical guidelines should be prepared for the assessment of the hygiene of distribution trays. In the graphical and statistical analysis, levels below 250 RLU/100 ㎠ was considered 'Pass', while equal to or greater than 350 RLU/100 ㎠ was considered 'Fail' for distribution trays.

Organic Enrichment and Pollution in Surface Sediments from Jinhae and Geoje-Hansan Bays with Dense Oyster Farms (굴양식어장 밀집해역인 진해만과 거제-한산만의 퇴적물 내 유기물 분포특성)

  • Choi, Minkyu;Lee, In-Seok;Hwang, Dong-Woon;Kim, Hyung Chul;Yoon, Sang-Pil;Yun, Sera;Kim, Chung-Sook;Seo, In-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.50 no.6
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    • pp.777-787
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    • 2017
  • Organic enrichment and pollution was investigated in surface sediments from Jinhae Bay and Geoje-Hansan Bay of Korea, which contain the largest oyster farms in Korean coastal areas. Geochemical indicators (chemical oxygen demand, total organic carbon, ignition loss, and acid volatile sulfide) in sediments, ammonium and nitrate in pore water, and bioluminescence inhibition test for sediment extracts were analyzed. Temporal changes of organic enrichment were also investigated using sediment core samples from Geoje-Hansan Bay. The level of organic pollution in sediments from Jinhae Bay was significantly greater than that of sediments from Geoje-Hansan Bay. Compared with other sites, Jinhae Bay was one of the most polluted coastal areas of Korea. The levels of geochemical indicators in May were comparable to, or higher than, in August. Ammonium concentrations in pore water were two orders of magnitudes greater than the nitrate concentrations, suggesting that the bays are reducing environments. The concentrations of total organic carbon in core sediment samples from shellfish-farming areas increased significantly from 2000 to the present year, and it seems to be associated with increases in anthropogenic activities.

Studies on the Culture Media and the Optimal Storage Conditions of Bioluminescent Bacteria Photobacterium phosphoreum (생체발광균주 Photobacterium phosphoreum의 배양배지 및 최적 저장조건에 관한 연구)

  • 조동욱;전억한;김병용;김은기;함영태
    • 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.

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A novel retentive type of dental implant prosthesis: marginal fitness of the cementless double crown type implant prosthesis evaluated by bacterial penetration and viability

  • Hong, Seoung-Jin;Kwon, Kung-Rock;Jang, Eun-Young;Moon, Ji-Hoi
    • 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.