Bioluminescent Bacteria

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Man Bock Gu - One of the best experts on this subject based on the ideXlab platform.

  • prescreening of natural products in drug discovery using recombinant Bioluminescent Bacteria
    Biotechnology and Bioprocess Engineering, 2019
    Co-Authors: Man Bock Gu
    Abstract:

    Strains of recombinant Bioluminescent Bacteria (RBB) which respond to toxic environments using various stress promoters are practical means of assessing toxicity. In previous research, RBB has proven useful for highthroughput screening in the drug development process. The goal of this research is to demonstrate that RBB can also be used for the toxicity screening of natural products. The RBB strains used were DPD2511, BBTSbmC, TV1061, and GC2, which were selected to respond to oxidative stress, DNA damage, protein damage, and cellular toxicity, respectively. The test drugs (paclitaxel, etoposide, and pentostatin) were carefully selected because these drugs needed to be natural products or their derivatives whose cellular toxicity had previously been reported from human cell line assays. After treating the RBB strains with various doses of the chosen drugs, their Bioluminescent signals were measured over time. The effectiveness of the RBB method was proven by comparing its results to existing toxicity data for the selected drugs. In addition, a similar test using podophyllotoxin, a precursor of etoposide, and a derivative of podophyllotoxin, teniposide, was conducted to prove that the RBB method is suitable for a comparative analysis of toxicity among chemicals with similar molecular structures. As a detection method, RBB Bacteria provide a much easier and more rapid culturing process compared to conventional human cell line assays. Because the implementation of the RBB method in the drug discovery process would enable efficient prescreening, a significant reduction in time, effort, and development costs are expected.

  • a dip stick type biosensor using Bioluminescent Bacteria encapsulated in color coded alginate microbeads for detection of water toxicity
    Analyst, 2014
    Co-Authors: Insup Jung, Man Bock Gu
    Abstract:

    The use of genetically engineered Bioluminescent Bacteria, in which bioluminescence is induced by different modes of toxic action, represents an alternative to acute toxicity tests using living aquatic organisms (plants, vertebrates, or invertebrates) in an aqueous environment. A number of these Bacterial strains have been developed, but there have been no attempts to develop a hand-held type of biosensor for monitoring or identification of toxicity. We report a facile dip-stick type biosensor using genetically engineered Bioluminescent Bacteria as a new platform for classification and identification of toxicity in water environments. This dip-stick type biosensor is composed of eight different optically color-coded functional alginate beads that each encapsulates a different Bioluminescent Bacterial strain and its corresponding fluorescent microbead. These color-coded microbeads exhibit easy identification of encapsulated microbeads, since each microbead has a different color code depending on the Bioluminescent Bacterial strain contained and improved cell-stability compared to liquid culture. This dip-stick type biosensor can discriminate different modes of toxic actions (i.e. DNA damage, oxidative damage, cell-membrane damage, or protein damage) of sample water tested by simply dipping the stick into the water samples. It was found that each color-coded microbead emitted distinct bioluminescence, and each dip-stick type biosensor showed different bioluminescence patterns within 2 hours, depending on the toxic chemicals contained in LB medium, tap water, or river water samples. This dip-stick type biosensor can, therefore, be widely and practically used in checking toxicity of water in the environment primarily in situ, possibly indicating the status of biodiversity.

  • Fabrication of a bio-MEMS based cell-chip for toxicity monitoring
    Biosensors and Bioelectronics, 2007
    Co-Authors: Sung Keun Yoo, Sung-sik Yun, Jin-hyung Lee, Man Bock Gu, Jong Hyun Lee
    Abstract:

    A bio-MEMS based cell-chip that can detect a specific toxicity was fabricated by patterning and immobilizing Bioluminescent Bacteria in a microfluidic chip. Since the emitted light intensity of Bioluminescent Bacteria changed in response to the presence of chemicals, the Bacteria were used as the toxicity indicator in this study. A pattern of immobilized cells was successfully generated by photolithography, utilizing a water-soluble and negatively photosensitive polymer, PVA-SbQ (polyvinyl alcohol-styrylpyridinium) as an immobilization material. Using the recombinant Escherichia coli (E. coli) strain, GC2, which is sensitive to general toxicity, the following were investigated for the immobilization: an acceptable dose of long-wavelength UV light, the biocompatibility of the polymer, and the effect of the chip-environment. We found that 10 min of UV light exposure, the toxicity of polymer (SPP-H-13-bio), and the other chip-environment did not inhibit cell metabolism significantly for making a micro-cell-chip. Detection of a specific toxicity was demonstrated by simply immobilizing the Bioluminescent Bacteria, DK1, which increased bioluminescence in the presence of oxidative damage in the cells. An injection of hydrogen peroxide of 0.88 mM induced 10-fold increase in Bioluminescent intensity confirming the capability of the chip for toxicity monitoring. © 2006 Elsevier B.V. All rights reserved.

  • Fabrication of a bio-MEMS based cell-chip for toxicity monitoring.
    Biosensors and Bioelectronics, 2006
    Co-Authors: Man Bock Gu
    Abstract:

    Abstract A bio-MEMS based cell-chip that can detect a specific toxicity was fabricated by patterning and immobilizing Bioluminescent Bacteria in a microfluidic chip. Since the emitted light intensity of Bioluminescent Bacteria changed in response to the presence of chemicals, the Bacteria were used as the toxicity indicator in this study. A pattern of immobilized cells was successfully generated by photolithography, utilizing a water-soluble and negatively photosensitive polymer, PVA-SbQ (polyvinyl alcohol-styrylpyridinium) as an immobilization material. Using the recombinant Escherichia coli ( E. coli ) strain, GC2, which is sensitive to general toxicity, the following were investigated for the immobilization: an acceptable dose of long-wavelength UV light, the biocompatibility of the polymer, and the effect of the chip-environment. We found that 10 min of UV light exposure, the toxicity of polymer (SPP-H-13-bio), and the other chip-environment did not inhibit cell metabolism significantly for making a micro-cell-chip. Detection of a specific toxicity was demonstrated by simply immobilizing the Bioluminescent Bacteria, DK1, which increased bioluminescence in the presence of oxidative damage in the cells. An injection of hydrogen peroxide of 0.88 mM induced 10-fold increase in Bioluminescent intensity confirming the capability of the chip for toxicity monitoring.

  • Application of a multi-channel system for continuous monitoring and an early warning system.
    Water Science and Technology, 2006
    Co-Authors: Chul H. Song, Man Bock Gu
    Abstract:

    A multi-channel continuous toxicity monitoring system developed in our laboratory, based on two-stage mini-bioreactors, was successfully implemented in the form of computer-based data acquisition. The multi-channel system consists of a series of a two-stage minibioreactor systems connected by a fiber optic probe to a luminometer, and uses genetically engineered Bioluminescent Bacteria for the detection of the potential toxicity from the soluble chemicals. This system can be stably and continuously operated due to the separation of the culture reactor from the test reactor and accomplish easy and long-term monitoring without system shut down by abrupt inflows of severe polluting chemicals. Four different recombinant Bioluminescent Bacteria were used in different channels so that the modes of the samples toxicities can be reasonably identified and evaluated based upon the response signature of each channel. The Bioluminescent signatures were delivered from four channels by switching one at once, while the data is automatically logged to an IBM compatible computer. We also achieved the enhancement of the system through the manipulation of the dilution rate and the use of thermo- lux fusion strains. Finally, this system is now being implemented to a drinking water reservoir and river for remote sensing as an early warning system.

Andre Ex Brown - One of the best experts on this subject based on the ideXlab platform.

  • measuring caenorhabditis elegans spatial foraging and food intake using Bioluminescent Bacteria
    Genetics, 2020
    Co-Authors: Siyu Serena Ding, Maksym Romenskyy, Karen S Sarkisyan, Andre Ex Brown
    Abstract:

    For most animals, feeding includes two behaviors: foraging to find a food patch and food intake once a patch is found. The nematode Caenorhabditis elegans is a useful model for studying the genetics of both behaviors. However, most methods of measuring feeding in worms quantify either foraging behavior or food intake, but not both. Imaging the depletion of fluorescently labeled Bacteria provides information on both the distribution and amount of consumption, but even after patch exhaustion a prominent background signal remains, which complicates quantification. Here, we used a Bioluminescent Escherichia coli strain to quantify C. elegans feeding. With light emission tightly coupled to active metabolism, only living Bacteria are capable of bioluminescence, so the signal is lost upon ingestion. We quantified the loss of bioluminescence using N2 reference worms and eat-2 mutants, and found a nearly 100-fold increase in signal-to-background ratio and lower background compared to loss of fluorescence. We also quantified feeding using aggregating npr-1 mutant worms. We found that groups of npr-1 mutants first clear Bacteria from within the cluster before foraging collectively for more food; similarly, during large population swarming, only worms at the migrating front are in contact with Bacteria. These results demonstrate the usefulness of Bioluminescent Bacteria for quantifying feeding and generating insights into the spatial pattern of food consumption.

  • measuring c elegans spatial foraging and food intake using Bioluminescent Bacteria
    bioRxiv, 2019
    Co-Authors: Siyu Serena Ding, Karen S Sarkisyan, Andre Ex Brown
    Abstract:

    ABSTRACT For most animals, feeding includes two behaviours: foraging to find a food patch and food intake once a patch is found. The nematode Caenorhabditis elegans is a useful model for studying the genetics of both behaviours. However, most methods of measuring feeding in worms quantify either foraging behaviour or food intake but not both. Imaging the depletion of fluorescently labelled Bacteria provides information on both the distribution and amount of consumption, but even after patch exhaustion a prominent background signal remains, which complicates quantification. Here, we used a Bioluminescent Escherichia coli strain to quantify C. elegans feeding. With light emission tightly coupled to active metabolism, only living Bacteria are capable of bioluminescence so the signal is lost upon ingestion. We quantified the loss of bioluminescence using N2 reference worms and eat-2 mutants, and found a nearly 100-fold increase in signal-to-background ratio and lower background compared to loss of fluorescence. We also quantified feeding using aggregating npr-1 mutant worms. We found that groups of npr-1 mutants first clear Bacteria from each other before foraging collectively for more food; similarly, during high density swarming, only worms at the migrating front are in contact with Bacteria. These results demonstrate the usefulness of Bioluminescent Bacteria for quantifying feeding and suggest a hygiene hypothesis for the function of C. elegans aggregation and swarming.

Paul D Frymier - One of the best experts on this subject based on the ideXlab platform.

  • Comparative Study of Two Bioassays for Applications in Influent Wastewater Toxicity Monitoring
    Journal of Environmental Engineering, 2003
    Co-Authors: Paul D Frymier
    Abstract:

    Bioluminescent Bacteria-based assays can be used for influent wastewater toxicity monitoring for biological wastewater treatment systems. The most thoroughly studied Bioluminescent Bacteria-based test is the Microtox® assay. However, the response to toxicants of Photobacterium phosphoreum, the marine Bacterial strain used in this assay, is different from that of the activated sludge microorganisms. We developed a continuous influent wastewater monitoring system based on the Bioluminescent bacterium Shk1, a genetically modified Pseudomonad isolated from the activated sludge in an industrial wastewater treatment plant. The Shk1 toxicity data were correlated with the Microtox® toxicity data for 79 organic compounds and the two toxicity assays were compared. The Shk1 assay is less sensitive than the Microtox® assay and could therefore be more suitable for influent wastewater toxicity monitoring.

  • estimating the toxicities of organic chemicals to Bioluminescent Bacteria and activated sludge
    Water Research, 2002
    Co-Authors: Paul D Frymier
    Abstract:

    Abstract Toxicity assays based on Bioluminescent Bacteria have several advantages including a quick response and an easily measured signal. The Shk1 assay is a procedure for wastewater toxicity testing based on the Bioluminescent bacterium Shk1. Using the Shk1 assay, the toxicity of 98 organic chemicals were measured and EC 50 values were obtained. Quantitative structure–activity relationship (QSAR) models based on the logarithm of the octanol–water partition coefficient (log( K ow )) were developed for individual groups of organic chemicals with different functional groups. The correlation coefficients for different groups of organic compounds varied between 0.69 and 0.99. An overall QSAR model without discriminating the functional groups, which can be used for a quick estimate of the toxicities of organic chemicals, was also developed and model predictions were compared to experimental data. The model accuracy was found to be one order of magnitude from the observed values.

Stefano Girotti - One of the best experts on this subject based on the ideXlab platform.

  • checking syrup adulteration of honey using Bioluminescent Bacteria and chemometrics
    European Food Research and Technology, 2019
    Co-Authors: Dora Melucci, Luca Bolelli, Alessandro Zappi, Francesca Corvucci, Giorgia Serra, Francescavittoria Grillenzoni, Giorgio Fedrizzi, Simonetta Menotta, Stefano Girotti
    Abstract:

    Accomplishing the Italian law to verify honey quality is onerous, because it requires measuring many chemical and physical parameters. On the contrary, bioluminescence-based analytical methods allow for rapid and inexpensive analysis. Bioluminescence has never been applied before to verify honey adulteration. The application of chemometrics to analytical methods based on bioluminescence has been here explored for this scope. Several honey samples were prepared, in which sugar syrup was added without exceeding legal limits: in this case, univariate analysis prescribed by the law cannot reveal the fraud. All samples were subjected to measurements of parameters prescribed by the law and also to bioluminescence analysis, executed using the Vibrio fischeri bacterium, one of the most common Bioluminescent Bacteria. Principal components analysis, linear discriminant analysis, and partial least square regression were applied to discriminate sugar-added honeys with respect to natural honeys, both by regulated physicochemical parameters and by bioluminescence ones. The feasibility of combining bioluminescence and multivariate analysis for a rapid screening of honey authenticity was demonstrated.

  • Optimal conditions for stability of photoemission and freeze drying of two luminescent Bacteria for use in a biosensor
    Environmental Toxicology and Chemistry, 2011
    Co-Authors: Laura Camanzi, Elisabetta Maiolini, Stefano Girotti, Luca Bolelli, Diego Matteuzzi
    Abstract:

    Bioluminescent Bacteria have been used for many years for biotoxicological analysis. One of the main concerns with this microorganism is the low experimental repeatability when subjected to external factors. The aim of the present study was to obtain accurate, sensitive, and repeatable measurements with stable signals (during the detection and over days) for application in a water-analysis device for the detection of pollutants. Growth conditions were tested and optimized. An optimal freeze-drying procedure for the constitutive Bioluminescent Bacteria Vibrio fischeri and Photobacterium phosphoreum was developed. The luminescence stability after rehydration was also investigated. Freeze drying was found to be a critical process in survival and signal stability of luminescent Bacteria; for this reason, different suspension fluids and various Bacterial pellet/suspension fluid ratios (g/ml) were evaluated. The toxicity of heavy metals and organic compounds in water was determined to investigate the applicability of a test based on Bacteria obtained in this way, comparing the data with legal limits. A scale-up process was developed with industrial technology: freeze-dried Bacteria that emitted a stable luminous signal after rehydration were obtained. Moreover, the median effective concentration (EC50) was calculated with these Bacteria. Environ. Toxicol. Chem. 2011; 30:801–805. © 2010 SETAC

  • Monitoring of environmental pollutants by Bioluminescent Bacteria.
    Analytica Chimica Acta, 2007
    Co-Authors: Stefano Girotti, Maria Grazia Fumo, Elida Ferri, Elisabetta Maiolini
    Abstract:

    This review deals with the applications of Bioluminescent Bacteria to the environmental analyses, published during the years 2000–2007. The ecotoxicological assessment, by bioassays, of the environmental risks and the luminescent approaches are reported. The review includes a brief introduction to the characteristics and applications of bioassays, a description of the characteristics and applications of natural Bioluminescent Bacteria (BLB), and a collection of the main applications to organic and inorganic pollutants. The light-emitting genetically modified Bacteria applications, as well as the Bioluminescent immobilized systems and biosensors are outlined. Considerations about commercially available BLB and BLB catalogues are also reported. Most of the environmental applications, here mentioned, of luminescent organisms are on wastewater, seawater, surface and ground water, tap water, soil and sediments, air. Comparison to other bioindicators and bioassay has been also made. Various tables have been inserted, to make easier to take a rapid glance at all possible references concerning the topic of specific interest.

  • trace metals in arcid clam scapharca inaequivalvis effects of molluscan extracts on Bioluminescent Bacteria
    Chemosphere, 2006
    Co-Authors: Stefano Girotti, Luca Bolelli, Fabiana Fini, Marta Monari, Giulia Andreani, Gloria Isani, E Carpene
    Abstract:

    The relationship between a supposed effect of molluscan extracts on Bioluminescent Bacteria and metal concentrations in the extracts was investigated. For this purpose a biotoxicological assay based on Bioluminescent Bacteria (BLB) and extracts from metal exposed molluscs, Scapharca inaequivalvis, was optimized to monitor Cd and Cu marine pollution. Cu and Cd concentrations increased in tissues of experimentally exposed molluscs. Molluscan extracts inhibited the Bacterial luminescence, the inhibition decreasing as the time of mollusc exposure to metals increased, suggesting a reduction of the “bioactive” metals. In regard to the use of BLB test in environmental monitoring, the analysis of Cu, Cd, and metallothionein (MT) was first performed in tissues from molluscs collected in three different areas of Northern Adriatic Sea. Metal concentrations reached maximum values in the gills, while Cd was mostly bound to MT in the kidney. Significant differences in metals and MT concentrations were found depending on the sampling sites. The biotoxicological assay resulted slightly correlated with the biochemical parameters.

  • Bioluminescent Bacteria assay of veterinary drugs in excreta of food producing animals
    Journal of Pharmaceutical and Biomedical Analysis, 2006
    Co-Authors: Luca Bolelli, Elida Ferri, Fabiana Fini, Giorgio Fedrizzi, Simonetta Menotta, Z Bobrovova, S Scandurra, Stefano Girotti
    Abstract:

    The residues of pharmacological treatments on food-producing animals, present in the manure dispersed on agricultural land, can impact environmental and human health through toxic, genotoxic, and drug-resistance development effects. Biotoxicity assays can easily reveal the presence of noxious substances and those based on Bioluminescent Bacteria (BLB) are particularly simple and rapid. A BLB assay was developed as microplate format by using various strains of Vibrio sp. and was employed to evaluate their response to pure antibiotic solutions and to residues extracted from excreta of antibiotic treated pigs and turkeys. The residues were quantified by HPLC analysis. The BLB assay can be proposed as an easy-to-perform screening tool to assess the presence of residues due to undeclared current, or recently ended, pharmacological treatments, as well as to evaluate their permanence in manure.

Mikhail Borisover - One of the best experts on this subject based on the ideXlab platform.

  • toxicity of chlorinated and ozonated wastewater effluents probed by genetically modified Bioluminescent Bacteria and cyanoBacteria spirulina sp
    Water Research, 2019
    Co-Authors: M. Bhuvaneshwari, Evgeni Eltzov, Boris Veltman, Orr H Shapiro, Giji Sadhasivam, Mikhail Borisover
    Abstract:

    Abstract Chlorination and ozonation of various waters may be associated with the formation of toxic disinfection byproducts (DBPs) and cause health risks to humans. Monitoring the toxicity of chlorinated and ozonated water and identification of different toxicity mechanisms are therefore required. This study is one of its kind to examine the toxic effects of chlorinated and ozonated wastewater effluents on three genetically modified Bioluminescent Bacteria, in comparison to the naturally isolated cyanoBacteria, Spirulina strains as test systems. Three different secondary wastewater effluents were collected from treatment plants, chlorinated using sodium hypochlorite (at 1 and 10 mg L−1 of chlorine) or treated using 3–4 mg L−1 of ozone at different contact times. As compared to cyanoBacterial Spirulina sp., the genetically modified Bacteria enhancing bioluminescence at the presence of stress agents demonstrated greater sensitivity to the toxicity induction and have also provided mechanism-specific responses associated with genotoxicity, cytotoxicity and reactive oxygen species (ROS) generation in wastewater effluents. Effects of effluent chlorination time and chlorine concentration revealed by means of Bioluminescent Bacteria suggest the formation of genotoxic and cytotoxic DBPs followed with their possible disappearance at longer times. Ozonation could degrade genotoxic compounds in some effluents, but the cytotoxic potential of wastewater effluents may certainly increase with ozonation time. No induction of ROS-related toxicity was detected in either chlorinated or ozonated wastewater effluents. UV absorbance- and fluorescence emission-based spectroscopic characteristics may be variously correlated with changes in genotoxicity in ozonated effluents, however, no associations were obtained in chlorinated wastewater effluents. The Bacterial response to the developed mechanism-specific toxicity differs among wastewater effluents, reflecting variability in effluent compositions.