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1.
生物超弱发光研究   总被引:5,自引:0,他引:5  
生物超弱发光是自然界普遍在的一种生命现象。本文概述了近年来生物超弱发光研究的进展,探讨了生物超弱发光在医学和农业上应用的可能性,并提出了该领域有待深入研究的问题。  相似文献   

2.
This study was conducted to investigate the applicability of the stimulant conditions for the bioluminescence activity of a recombinant strain of Pseudomonas putida, mt-2 KG1206, when immobilized using alginate polymer. The bioluminescence activity of the immobilized strain was generally approximately three to five times lower than the subcultured strain, and the activity was observed to slowly decrease. These facts may have been caused by several factors, such as the low biomass and the time required for diffusion into the entrapped biomass. Although different inducers produced different degrees of stimulation, immobilized bacteria modified with KNO3 consistently produced more bioluminescence than those treated with sodium lactate, regardless of the inducer chemical tested. Cells treated with KNO3 exhibited 2.8 times greater bioluminescence than that of the control activity. This condition also stimulated the bioluminescence activities of the immobilized bacteria exposed to contaminated groundwater samples. Based on these results, the immobilized KG1206 presented in this research can be used as a portable assay for the purpose of preliminary on-site monitoring of specific inducer contaminants, with subsequent off-site instrumental analysis, suggesting the potential of this immobilized cell for preliminary application in a field-ready bioassay.  相似文献   

3.
Jun Wang  Yong Yu 《Luminescence》2009,24(4):209-212
Ultra‐weak luminescent analysis is a new way to detect the irradiation dose and the vigour of irradiated wheat. Wheat grain and wheat flour were used in this research for ultra‐weak luminescent analysis. The experimental data showed that the bioluminescence intensity of wheat grain sample was different with increasing storage time and increasing dose, and a similar trend appeared in the germination rates of irradiated wheat grain. It was found that the differences in bioluminescence intensities and germination rates of irradiated wheat grain at different doses and storage times were due to the effect of irraditation on the wheat embryo and self‐repair during storage. As a result, ultra‐weak luminescent analysis cannot be used to detect the irradiation dose of irradiated wheat, but it can be used to determine vigour. Experiments showed that the irradiation dose had a highly significant effect on the bioluminescence intensities of wheat flour when cane sugar was added. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

4.
活体生物发光与荧光成像技术是近年发展起来的新兴技术,以其操作简便、灵敏度高、创伤性小在生命科学研究中有着较大的优势,目前已被广泛应用于基因标记、细胞凋亡、免疫细胞研究、肿瘤转移等诸多领域,尤其在新兴的干细胞研究方面更是发挥着不可替代的作用。综述了活体生物发光与荧光成像技术的原理、优势、应用范围及发展前景,特别对近年来该技术在胚胎干细胞的肝向分化、人造血干细胞重建小鼠造血系统、神经祖细胞治疗中枢神经系统肿瘤等方面的应用做了详细介绍。  相似文献   

5.
Bioluminescence has recently become a popular research tool in several fields, including medicine, pharmacology, biochemistry, bioprocessing, and environmental engineering. Beginning with purely qualitative goals, scientists are now targeting more demanding applications where accurate, quantitative interpretation of bioluminescence is necessary. Using the recent advances in fiber-optic technology, bioluminescence is easily monitored in vivo and in real time. However, the convenience of this measurement is often concealing an unsuspected problem: the bioluminescence signal might be corrupted by a large error caused by the extinction of light by biological cells. Since bioluminescent cultures not only emit light but also absorb and scatter it, the measured signal is related in a complex, nonlinear, and cell-concentration-dependent manner to the "true" bioluminescence. This light extinction effect, known as the "inner filter effect," is significant in high-density cultures. Adequate interpretation of the bioluminescence signal can be difficult without its correction. Here, we propose a real-time algorithm for elimination of the inner filter effect in a bioreactor. The algorithm yields the bioluminescence which would be measured if the glowing culture was completely transparent. This technique has been successfully applied to batch and continuous cultivation of recombinant bioluminescent Escherichia coli. (c) 1993 John Wiley & Sons, Inc.  相似文献   

6.
Evolutionary convergence provides natural opportunities to investigate how, when, and why novel traits evolve. Many convergent traits are complex, highlighting the importance of explicitly considering convergence at different levels of biological organization, or ‘multi-level convergent evolution’. To investigate multi-level convergent evolution, we propose a holistic and hierarchical framework that emphasizes breaking down traits into several functional modules. We begin by identifying long-standing questions on the origins of complexity and the diverse evolutionary processes underlying phenotypic convergence to discuss how they can be addressed by examining convergent systems. We argue that bioluminescence, a complex trait that evolved dozens of times through either novel mechanisms or conserved toolkits, is particularly well suited for these studies. We present an updated estimate of at least 94 independent origins of bioluminescence across the tree of life, which we calculated by reviewing and summarizing all estimates of independent origins. Then, we use our framework to review the biology, chemistry, and evolution of bioluminescence, and for each biological level identify questions that arise from our systematic review. We focus on luminous organisms that use the shared luciferin substrates coelenterazine or vargulin to produce light because these organisms convergently evolved bioluminescent proteins that use the same luciferins to produce bioluminescence. Evolutionary convergence does not necessarily extend across biological levels, as exemplified by cases of conservation and disparity in biological functions, organs, cells, and molecules associated with bioluminescence systems. Investigating differences across bioluminescent organisms will address fundamental questions on predictability and contingency in convergent evolution. Lastly, we highlight unexplored areas of bioluminescence research and advances in sequencing and chemical techniques useful for developing bioluminescence as a model system for studying multi-level convergent evolution.  相似文献   

7.
We validated a new method, based on luciferine/luciferase bioluminescence, for drug screening on promastigotes of different Leishmania species. Results obtained with this new, rapid, reproducible, and reliable method are in good accordance with results obtained by the conventional MTT assay. This bioluminescence assay has a lower detection limit.  相似文献   

8.
发光蚯蚓的发光体系研究进展   总被引:1,自引:0,他引:1  
修立辉  梁醒财 《四川动物》2007,26(1):201-205
发光蚯蚓在世界范围内广泛分布。大多数发光蚯蚓的发光体系包含于蚯蚓体腔液内充满颗粒的细胞内。早期对不同种发光蚯蚓的生理学及生物化学方面的对比研究表明大多数发光蚯蚓的发光体系是类似的,但最近对线蚓科的两个种的研究发现它们不仅发光源的定位特殊,而且发光反应所需要的成分也明显不同于其他种类。本文对发光蚯蚓的发光器官和发光体系的研究现状及其进展进行了综述,并将有代表性的发光蚯蚓的发光体系进行了对比总结。  相似文献   

9.
The chemical mechanisms underlying visible bioluminescence in the fungus Mycena chlorophos are not clear. A combination of dihydronicotinamide adenine dinucleotide phosphate (NADPH) and hispidin, which has been reported to increase the intensity of in vitro luminescence in crude cold‐water extracts prepared from the bioluminescent fruiting bodies of M. chlorophos, exhibited potential bioluminescence activation in the early bioluminescence stages, in which the bioluminescence was ultra‐weak, for living gills and luminescence activation for non‐bioluminescent gills, which was collapsed by freezing and subsequent thawing, at all bioluminescence stages. These abilities were not evident in considerably bioluminescent gills. These abilities were blocked by trans‐4‐hydroxycinnamic acid and trans‐3,4‐dihydroxycinnamic acid, which were identified as in vivo bioluminescence‐activating components. Original bioluminescence and bioluminescence produced from the addition of trans‐4‐hydroxycinnamic acid and trans‐3,4‐dihydroxycinnamic acid in living gills were almost completely inhibited by 10 mM NaN3, whereas the luminescence produced form the combination of NADPH and hispidin in thawed non‐bioluminescent and living gills at the early weak bioluminescence stages was not inhibited by 10 mM NaN3. Thus, the combination of NADPH and hispidin plays different roles in luminescence systems compared with essential bioluminescence systems, and the combination of NADPH and hispidin was not essential for visible bioluminescence in living gills.  相似文献   

10.
Bioluminescence bioassays based on luminous bacteria (Photobacterium phosphopreum) and coupled enzyme system NADH-FMN-oxidoreductase-luciferase were adapted for monitoring the saline-water conditions of Lake Shira (Khakasia, Siberia). The differences in bioluminescence responses have been found to be related to the salt composition and the oxidation-reduction properties of water. Bioluminescent kinetics parameters, which are mostly sensitive to pollution under conditions of saline water, have been observed. The enzymatic system in the presence of 1,4-benzoquinone are shown to be more sensitive to redox characteristics of the salt water than this in the absence of 1,4-benzoquinone. 1,4-benzoquinone should be applied for the preparation of a model solution for the monitoring of redox properties of the salt water. Using this technique, the results of bioluminescence analysis are used to construct a heterogeneity map that characterizes the spatial and temporal water quality of lake Shira. A partial map was based on the bioluminescence characteristics of water samples taken along the shoreline, sampling stations in the different places and in different depths of the lake. It has been demonstrated that the bioluminescence assay measurements must be done within two hours after the sampling time.  相似文献   

11.
Noninvasive bioluminescence imaging in small animals   总被引:3,自引:0,他引:3  
There has been a rapid growth of bioluminescence imaging applications in small animal models in recent years, propelled by the availability of instruments, analysis software, reagents, and creative approaches to apply the technology in molecular imaging. Advantages include the sensitivity of the technique as well as its efficiency, relatively low cost, and versatility. Bioluminescence imaging is accomplished by sensitive detection of light emitted following chemical reaction of the luciferase enzyme with its substrate. Most imaging systems provide 2-dimensional (2D) information in rodents, showing the locations and intensity of light emitted from the animal in pseudo-color scaling. A 3-dimensional (3D) capability for bioluminescence imaging is now available, but is more expensive and less efficient; other disadvantages include the requirement for genetically encoded luciferase, the injection of the substrate to enable light emission, and the dependence of light signal on tissue depth. All of these problems make it unlikely that the method will be extended to human studies. However, in small animal models, bioluminescence imaging is now routinely applied to serially detect the location and burden of xenografted tumors, or identify and measure the number of immune or stem cells after an adoptive transfer. Bioluminescence imaging also makes it possible to track the relative amounts and locations of bacteria, viruses, and other pathogens over time. Specialized applications of bioluminescence also follow tissue-specific luciferase expression in transgenic mice, and monitor biological processes such as signaling or protein interactions in real time. In summary, bioluminescence imaging has become an important component of biomedical research that will continue in the future.  相似文献   

12.
A review of the research conducted during the past 30 years on the distribution, taxonomy, phylogeny, ecology, physiology and bioluminescence mechanisms of luminescent fungi is presented. We recognize 64 species of bioluminescent fungi belonging to at least three distinct evolutionary lineages, termed Omphalotus, Armillaria and mycenoid. An accounting of their currently accepted names, distributions, citations reporting luminescence and whether their mycelium and/or basidiomes emit light are provided. We address the physiological and ecological aspects of fungal bioluminescence and provide data on the mechanisms responsible for bioluminescence in the fungi.  相似文献   

13.
Circadian rhythm is a self-sustaining oscillation whose period length coincides with the 24-hour day-night cycle. A powerful tool for circadian clock research is the real-time automated bioluminescence monitoring system in which a promoter region of a clock-controlled gene is fused to a luciferase reporter gene and rhythmic regulation of the promoter activity is monitored as bioluminescence. In the present study, we greatly improved the bioluminescence reporter system in the cyanobacterium Synechocystis sp. strain PCC 6803. We fused an 805-bp promoter region of the dnaK gene seamlessly to the luxA coding sequence and integrated the P(dnaK)::luxAB fusion gene into a specific intergenic region of the Synechocystis genome (targeting site 1). The resulting new reporter strain, PdnaK::luxAB(-), showed 12 times the bioluminescence intensity of the standard reporter strain, CFC2. Furthermore, we generated strain PdnaK::luxAB(+), in which the P(dnaK)::luxAB fusion gene and the selection-marker spectinomycin resistance gene are transcribed in opposite directions. The PdnaK::luxAB(+) strain showed 19 times the bioluminescence intensity of strain CFC2. The procedures used to increase the bioluminescence intensity are especially useful for bioluminescence monitoring of genes with low promoter activity. In addition, these reporter constructs facilitate bioluminescence monitoring of any gene because the promoter fragments they contain can easily be replaced by digestion with unique restriction enzymes. They would therefore contribute to a genome-wide analysis of gene expression in Synechocystis.  相似文献   

14.
The excitation of bioluminescence by different flow regimes generated within a Couette chamber was examined using the dinoflagellates Pyrocystis noctiluca. Cultured cells of P. noctiluca were gently transferred into a cylindrical Couette chamber in a dark room. In initial experiments, the velocity of the outer Couette cylinder was then gradually increased. The bioluminescence emissions in response to stationary-laminar and turbulent flows were quantified using a photomultiplier tube. Video images were also recorded in order to identify the location of bioluminescence emissions within the Couette chamber. Reflective flake flow visualizations were used to correlate these locations to the flow regimes in those parts of the chamber. These experiments clearly demonstrated that the strongest bioluminescence emissions were only triggered by the onset of turbulence at high rotation speeds. Below the turbulence threshold, much lower bioluminescence emissions were detected and appeared to be in response to a nonhomogeneity in the stationary-laminar flow (end cap effects and Ekman cells). In a second set of experiments, the excitation of bioluminescence in response to acceleration was studied by abrupt starts of the rotating Couette cylinder. These experiments also triggered massive bioluminescence emissions. We conclude that pure laminar-stationary, homogenous shear flow excites very little bioluminescence in P. noctiluca. The bulk of bioluminescence emissions primarily occurred under nonhomogenous or nonstationary flow conditions, where the cells experience velocity changes as they move through the flow. These findings are discussed in relation to the theory that bioluminescence in dinoflagellates is an antipredation mechanism.  相似文献   

15.
Real-time monitoring of gene expression by a bioluminescence reporter gene is a powerful method for large-scale, detailed analysis of gene expression in living cells and large-scale screening of mutants. We have developed a portable, compact, integrated automatic bioluminescence-monitoring apparatus that can continuously monitor 960 individual plant seedlings or micro-organism colonies under uniform light conditions at temperatures up to 50 °C. The apparatus gave reproducible and reliable results for both bioluminescence photon counts and period length of bioluminescence rhythms of Arabidopsis reporter strain. Using the apparatus, we measured bioluminescence rhythms in the thermophilic cyanobacterium Thermosynechococcus at temperature up to 43 °C. We also monitored the expression of the flowering regulator gene CONSTANS in Arabidopsis as bioluminescence in high time resolution under different photoperiodic conditions. The high-throughput bioluminescence-monitoring apparatus developed here is a powerful tool for real-time monitoring of gene expression and gene function.  相似文献   

16.
The spatial variability of the vertical structure of bioluminescence intensity has been studied along the Crimean coast in the spring period. The location of a layer with a high intensity of bioluminescence has been determined and its dependence on hydrological characteristics and thermohaline structure of waters is shown. Structurization of the spatial variability of bioluminescence intensity has been made. Four regions that are distinguished by the pattern of the vertical distribution of the bioluminescence intensity have been distinguished in coastal waters of the Crimean Peninsula.  相似文献   

17.

A modified Robbins device (MRD) has frequently been used as a model system to study adhesion and biofilm formation. This study investigates the reproducibility of attachment and whether a statistically significant gradient of adhesion exists along the 25 sampling ports of a MRD. A simple, quantitative, non‐destructive, bioluminescence assay was developed in order to measure attachment of bioluminescent P. veronii BL146bio cells to plastic discs of Thermanox? in newly modified Robbins devices (nMRD). No statistically significant difference in mean bioluminescence values occurred between pairs of nMRDs run in parallel, but there was a significant difference in bioluminescence values between different batches of bacteria (p < 0.05). Generalised Linear Modelling showed that the position of the sample disc influenced the numbers attaching. In 50% of devices a significant positive gradient of attachment occurred and bioluminescence values varied from disc 1 to disc 25 by 29.6–58.0%. In the other 50% of nMRDs there was a smaller, non‐significant gradient. A disc sampling regime was devised to take this gradient into account and used to prove a positive correlation between bioluminescence and numbers of viable P. veronii BL146bio cells during a 6h biofilm accumulation period.  相似文献   

18.
Elemental sulphur (as S0 and S8) is abundant in anaerobic sediments and soil, and is highly toxic in the Vibrio fischeri bioluminescence test. This mode of S0 action remains uncertain. The objective of this research was the analysis of the toxic effects of S0 on bioluminescence and respiration in V. fischeri, in joint action with N-ethylmaleimide (NEM) or 2,4-dithio-DL-threitol (DTT), which are -SH group inhibiting and maintaining synthetic agents, respectively. Non-toxic DTT immediately protected cell bioluminescence against S0 inhibition at low (5.5ppb) and high (55ppb) concentrations of S0, whilst restoration of the inhibitory effect of S0 took up to 30 minutes. NEM (62.5ppb) diminished cell bioluminescence by up to 50% after 5 minutes, but after 60 minutes, the inhibition reached 100%. DTT restored the bioluminescence function inhibited in vivo and in vitro by S0 and NEM. Enhancement of cell respiration by up to 20% and 33% was observed at 2.2ppm of S0 and 36.8ppm of 2,4-dinitrophenol (2,4-DNP; an uncoupler of oxidative phosphorylation), respectively; whilst NEM (3.1ppm) caused a reduction of up to 40%. This comparative analysis confirmed that S0 has multiple modes of action--it acts as both an -SH group inhibitor and an uncoupler of oxidative phosphorylation in V. fischeri cells.  相似文献   

19.
For applications in field experiments, the recombinant strain Salmonella typhimurium TA1535 was immobilized to permit its immediate utilization after long storage periods. Salmonella typhimurium TA1535 cells contain the plasmid that has an inducible SOS promoter fused to a promoterless luxCDABFE operon from Photobacterium leiognathi. The induction of bioluminescence occurs in the presence of the DNA-damaging agent mitomycin C which stimulates the bacterial SOS response. Early stationary phase cells were immobilized at a cell concentration of 10(10) CFU/ml in microtiter plates and stored up to 6 weeks at 4 degrees C in a sealed container. Even after 4 weeks of storage, the bioluminescence kinetics and yield in response to different concentrations of mitomycin C were not significantly different from those of freshly prepared samples.  相似文献   

20.
Seven hypotheses on relationships between the structure of naphthalene analogs and bioluminescence response of bioreporter Pseudomonas fluorescens were formulated using GUHA (General Unary Hypotheses Automaton) on a training set of 37 compounds. Prediction of bioluminescence response of 12 new naphthalene analogs was successful in 69 % cases and resulted in rejection of single hypothesis. The results demonstrate applicability of GUHA in structure-activity research, especially for qualitative data.  相似文献   

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