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1.
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   

2.
Bioluminescence is a biochemical process occurring in many organisms. Bacterial bioluminescence has been investigated extensively that lead to many applications of such knowledge. Quorum sensing in the bioluminescent bacteria is a chemical signal process to recognize the strength of its own population to start luminescence in harmony. There is a mechanism in these bacteria to also recognize inter‐species strength. When there is a higher number of these bacteria, the possibility and frequency of cell–cell physical contact will be high. In this study, the physical proximity was artificially enhanced between cells and the effect on luminescence in the concentrated cells in the normal culture medium and in the presence of other non‐bacterial cell‐free supernatants was investigated. The role of such physical contact in the quorum sensing in the bioluminescence is not known. Increase in the luminescence of V. fischeri when concentrated shows that the presence of physical proximity facilitates the quorum sensing for their bioluminescence. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

3.
ATP生物发光测定试剂研究进展   总被引:1,自引:0,他引:1  
萤火虫荧光素酶是ATP生物发光试剂的关键组成部分,可通过萤火虫尾提取纯化或基因工程技术制备,酶的活力和纯度决定了ATP生物发光试剂的性能。迄今许多先进技术在ATP生物发光试剂的制备中均有应用,包括酶基因工程改造技术、ATP循环的酶法放大技术、荧光素酶蛋白的活力及发光稳定技术,特异的细胞ATP提取技术等。ATP生物发光试剂的研究焦点主要集中在提高发光试剂的检测灵敏度和性能、增加产品的适应性等方面。  相似文献   

4.
Photon imaging is a new technique for the quantitative analysis of bioluminescence and chemiluminescence and can be performed both at the macro and micro levels. The high sensitivity and spatial resolution of photon-counting cameras have resulted in the development of new applications in the life sciences. At the macro level, imaging is a valuable tool for the rapid identification of biological samples emitting long-lasting glows in assays using microtitre plates or filter formats (immunoassays, DNA probes, phagocytosis, gene expression, metabolite and drug analysis) and also for in vivo studies of promoter activity. At the micro level, low-light imaging can be used for analysing multiple analytes on micro sensors and for advanced cell analysis (immunocytology, in situ hybridization, identification of cells or tissues expressing the luciferase gene, intracellular or intercellular protein traffic, metabolite analysis and imaging of Ca2+ flux and phosphorylation reactions). Two-dimensional photon-counting instrumentation is a versatile and powerful research tool for imaging and is complementary to conventional luminometers. The main applications to the life sciences involve many types of luminescence assays and can be performed on multiple samples in standard and non-standard formats. Photon-counting coupled to imaging is very helpful in selecting microorganisms or cells expressing bioluminescent genes. Measurements can be made in vitro and in vivo with a sensitivity comparable to that of phototube luminometers.  相似文献   

5.
The manufacturing processes of many electronic and medical products demand the use of high-quality water. Hence the water supply systems for these processes are required to be examined regularly for the presence of microorganisms and microbial biofilms. Among commonly used bacteria detection approaches, the ATP luminescence assay is a rapid, sensitive, and easy to perform method. The aim of this study is to investigate whether ATP regeneration from inorganic pyrophosphate, a product of the ATP luminescence assay, can stabilize the bioluminescence signals in ATP detection. ADPglc pyrophosphorylase (AGPPase), which catalyzes the synthesis of ATP from PPi in the presence of ADPglc, was selected because the system yields much lower luminescence background than the commercially available ATP sulfurylase/adenosine 5′-phosphosulfate (APS) system which was broadly used in pyrosequencing technology. The AGPPase-based assay could be used to measure both PPi and ATP quantitatively and shows 1.5- to 4.0-fold slight increases in a 10-min assay. The method could also be used to stabilize the luminescence signals in detection of Escherichia coli, Pseudomonas aeruginosa, and Bacillus cereus in either broth or biofilm. These findings suggest that the AGPPase-based ATP regeneration system will find many practical applications such as detection of bacterial biofilm in water pipelines.  相似文献   

6.
We recently developed a novel bioluminescent enzymatic cycling assay for ATP and AMP with the concomitant use of firefly luciferase and pyruvate orthophosphate dikinase (PPDK), where AMP and pyrophosphate produced from ATP by firefly luciferase were converted back into ATP by PPDK. Background luminescence derived from contaminating ATP and AMP in the reagent was reduced using adenosine phosphate deaminase which degrades ATP, ADP, and AMP, resulting in constant and highly amplified bioluminescence with low background luminescence. To detect bacterial cells without cultivation, we applied the above bioluminescent enzymatic cycling reagent to rapid microbe detection system. ATP spots (0.31-5.0 amol/spot) at the level of a single bacterial cell were detected with 5 min signal integration, signifying that integrated luminescence was amplified 43 times in comparison to traditional ATP bioluminescence. Consequently, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Lactobacillus brevis in beer were detected without cultivation. Significant correlation was observed between the number of signal spots obtained using this novel system and the colony-forming units observed with the conventional colony-counting method (R(2)=0.973).  相似文献   

7.
We constructed a novel ATP amplification reactor using a continuous-flow system, and this allowed us to increase the sensitivity of a quantitative bioluminescence assay by controlling the number of ATP amplification cycles. We previously developed a bioluminescence assay coupled with ATP amplification using a batch system. However, it was difficult to control the number of amplification cycles. In this study, ATP amplification was performed using a continuous-flow system, and significant linear correlations between amplified luminescence and initial ATP concentration were observed. When performing four cycles of continuous-flow ATP amplification, the gradient of amplification was 1.87N. Whereas the lower quantifiable level was 500 pM without amplification, values as low as 50 pM ATP could be measured after amplification. The sensitivity thus increased 10-fold, with further improvements expected with additional amplification cycles. The continuous-flow system thus effectively increased the sensitivity of the quantitative bioluminescence assay.  相似文献   

8.
生物发光及化学发光在生物医学领域中应用的进展   总被引:10,自引:0,他引:10  
生物发光和化学发光在生物医学领域内的应用主要包括细胞学检测,分子生物学、卫生学检测,生物传感器、脂质过氧化检测和药物筛选等六个方面,其中细胞学检测主要是利用细胞内ATP导致的虫荧光素酶发光进行活细胞计数,目前已实现快速、动态、单细胞分析;同时发现了一些新的与生物或化学发光有关的细胞学指标。分子生物学领域内的应用主要为报告基因和分子杂交,近年来又有人推出了生物发光实时DNA测序技术。卫生学检测则主要  相似文献   

9.
The assimilable organic carbon (AOC) test is a standardized measure of the bacterial growth potential of treated water. We describe the design and initial development of an AOC assay that uses bioluminescent derivatives of AOC test bacteria. Our assay is based on the observation that bioluminescence peaks at full cell yield just prior to the onset of the stationary phase during growth in a water sample. Pseudomonas fluorescens P-17 and Spirillum sp. strain NOX bacteria were mutagenized with luxCDABE operon fusion and inducible transposons and were selected on minimal medium. Independent mutants were screened for high luminescence activity and predicted AOC assay sensitivity. All mutants tested were able to grow in tap water under AOC assay conditions. Strains P-17 I5 (with p-aminosalicylate inducer) and NOX I3 were chosen for use in the bioluminescence AOC test. Peak bioluminescence and plate count AOC were linearly related for both test bacteria, though data suggest that the P-17 bioluminescence assay requires more consistent luminescence monitoring. Bioluminescence results were obtained 2 or 3 days postinoculation, compared with 5 days for the ATP luminescence AOC assay and 8 days for the plate count assay. Plate count AOC assay results for nonmutant and bioluminescent bacteria from 36 water samples showed insignificant differences, indicating that the luminescent bacteria retained a full range of AOC measurement capability. This bioluminescence method is amenable to automation with a microplate format with programmable reagent injection.  相似文献   

10.
Bacteria monitoring is essential for many industrial manufacturing processes, particularly those involving in food, biopharmaceuticals, and semiconductor production. Firefly luciferase ATP luminescence assay is a rapid and simple bacteria detection method. However, the detection limit of this assay for Escherichia coli is approximately 104 colony-forming units (CFU), which is insufficient for many applications. This study aims to improve the assay sensitivity by simultaneous conversion of PPi and AMP, two products of the luciferase reaction, back to ATP to form two chain-reaction loops. Because each consumed ATP continuously produces two new ATP molecules, this approach can achieve exponential amplification of ATP. Two consecutive enzyme reactions were employed to regenerate AMP into ATP: adenylate kinase converting AMP into ADP using UTP as the energy source, and acetate kinase catalyzing acetyl phosphate and ADP into ATP. The PPi-recycling loop was completed using ATP sulfurylase and adenosine 5′ phosphosulfate. The modification maintains good quantification linearity in the ATP luminescence assay and greatly increases its bacteria detection sensitivity. This improved method can detect bacteria concentrations of fewer than 10 CFU. This exponential ATP amplification assay will benefit bacteria monitoring in public health and manufacturing processes that require high-quality water.  相似文献   

11.
ATP bioluminescence rapid detection of total viable count in soy sauce   总被引:1,自引:0,他引:1  
The adenosine triphosphate (ATP) bioluminescence rapid determination method may be useful for enumerating the total viable count (TVC) in soy sauce, as it has been previously used in food and beverages for sanitation with good precision. However, many factors interfere with the correlation between total aerobic plate counts and ATP bioluminescence. This study investigated these interfering factors, including ingredients of soy sauce and bacteria at different physiological stages. Using the ATP bioluminescence method, TVC was obtained within 4 h, compared to 48 h required for the conventional aerobic plate count (APC) method. Our results also indicated a high correlation coefficient (r = 0.90) between total aerobic plate counts and ATP bioluminescence after filtration and resuscitation with special medium. The limit of quantification of the novel detection method is 100 CFU/mL; there is a good linear correlation between the bioluminescence intensity and TVC in soy sauce in the range 1 × 102–3 × 104 CFU/mL and even wider. The method employed a luminescence recorder (Tristar LB‐941) and 96‐well plates and could analyse 50–100 samples simultaneously at low cost. In this study, we evaluated and eliminated the interfering factors and made the ATP bioluminescence rapid method available for enumerating TVC in soy sauce. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

12.
The importance of having a rapid method for determining the viable biomass in activated-sludge wastewater treatment plants (WWTP) for process control and development is well recognized. The firefly bioluminescence ATP assay has been proposed for this purpose. Such an assay using partially purified firefly luciferase and synthetic firefly luciferin for the bioluminescence reaction, a liquid scintillation counter in the out-of-coincidence mode as luminescence detector, and a sludge ATP extraction technique involving dimethyl sulfoxide at room temperature is described. Experiments with several pure bacteria cultures were done to demonstrate the feasibility of applying this assay to activated sludge to activated sludge WWTP investigation and control. The ATP content of samples taken from various points in a 350000 gal/day brewery activated-sludge WWTP was monitored for 4.5 months. Good linear correlation between ATP and mixed-liquor suspended solids, return sludge suspended solids, and effluent suspended solids were observed. Percentage viabilities of the various sludge samples were derived from the ATP results.  相似文献   

13.
ATP methodology needs to be further standardized and improved in order to avoid the pitfalls that have sometimes hampered its application to biomass assays. The following steps have been reconsidered as far as the bacteriological applications is concerned:
  • destruction of free and somatic ATP: replacement of apyrase by mammalian ATPase, more readily accessible to specific inhibition;
  • extraction of bacterial ATP: protection of luciferase by lipids against inhibitory effect of cationic detergents with production of a constant light response.
New methods are proposed for the calibration of luminometers and for the matching of sample holders in multichannel instruments. The limit of sensitivity of ATP assays is discussed in the light of currently available reagents and instruments.  相似文献   

14.
Terebelliformia is a benthic group of marine annelid worms. The bioluminescence of several species has been reported in taxonomical and histological literature, but very little information is known about the biochemical aspects of this phenomenon. In this study, we examined the basic properties of the luminescence system using an extract of the Japanese terebelliform worm, Thelepus japonicus. The bioluminescence extract was soluble in water, and emitted blue‐green light at λmax 508 nm following the addition of divalent cations. This triggering action was highly specific to Fe2+ and addition of ATP, H2O2 or coelenterazine did not enhance activity. The bioluminescence was inactivated by heat treatment and organic solvents, indicating the involvement of a protein component. These results suggested that Thelepus worm produces light using a novel system that differs from that in other known luminescent annelids.  相似文献   

15.
The assimilable organic carbon (AOC) test is a standardized measure of the bacterial growth potential of treated water. We describe the design and initial development of an AOC assay that uses bioluminescent derivatives of AOC test bacteria. Our assay is based on the observation that bioluminescence peaks at full cell yield just prior to the onset of the stationary phase during growth in a water sample. Pseudomonas fluorescens P-17 and Spirillum sp. strain NOX bacteria were mutagenized with luxCDABE operon fusion and inducible transposons and were selected on minimal medium. Independent mutants were screened for high luminescence activity and predicted AOC assay sensitivity. All mutants tested were able to grow in tap water under AOC assay conditions. Strains P-17 I5 (with p-aminosalicylate inducer) and NOX I3 were chosen for use in the bioluminescence AOC test. Peak bioluminescence and plate count AOC were linearly related for both test bacteria, though data suggest that the P-17 bioluminescence assay requires more consistent luminescence monitoring. Bioluminescence results were obtained 2 or 3 days postinoculation, compared with 5 days for the ATP luminescence AOC assay and 8 days for the plate count assay. Plate count AOC assay results for nonmutant and bioluminescent bacteria from 36 water samples showed insignificant differences, indicating that the luminescent bacteria retained a full range of AOC measurement capability. This bioluminescence method is amenable to automation with a microplate format with programmable reagent injection.  相似文献   

16.
Due to the strict enantioselectivity of firefly luciferase, only d-luciferin can be used as a substrate for bioluminescence reactions. Unfortunately, luciferin racemizes easily and accumulation of nonluminous l-luciferin has negative influences on the light emitting reaction. Thus, maintaining the enantiopurity of luciferin in the reaction mixture is one of the most important demands in bioluminescence applications using firefly luciferase. In fireflies, however, l-luciferin is the biosynthetic precursor of d-luciferin, which is produced from the L-form undergoing deracemization. This deracemization consists of three successive reactions: l-enantioselective thioesterification by luciferase, in situ epimerization, and hydrolysis by thioesterase. In this work, we introduce a deracemizative luminescence system inspired by the biosynthetic pathway of d-luciferin using a combination of firefly luciferase from Luciola cruciata (LUC-G) and fatty acyl-CoA thioesterase II from Escherichia coli (TESB). The enzymatic reaction property analysis indicated the importance of the concentration balance between LUC-G and TESB for efficient d-luciferin production and light emission. Using this deracemizative luminescence system, a highly sensitive quantitative analysis method for l-cysteine was constructed. This LUC-G-TESB combination system can improve bioanalysis applications using the firefly bioluminescence reaction by efficient deracemization of D-luciferin.  相似文献   

17.
Shewanella woodyi cultures were used to correlate bioluminescence intensity with changes in the electrochemical potential of a saltwater medium using soluble electron acceptors. A relationship between the concentration of NaNO3 or CoCl2 to bioluminescence intensity was confirmed using aerobic cultures of S. woodyi at 20°C with glucose as the sole carbon source. In general, increasing the concentration of nitrate or Co(II) reduced the bioluminescence per cell, with complete luminescence being repressed at ≥5 mM nitrate and ≥0.5 mM Co(II). Results from cell viability fluorescent staining concluded that increasing the concentration of Co(II) or nitrate did not affect the overall viability of the cells when compared with cultures lacking Co(II) or nitrate. These data show that potentials of <0.2 V vs Normal Hydrogen Electrode (NHE) repress the luminescence from the cells, but the exact mechanism is unclear. Our results indicated that the luminescence intensity from S. woodyi could be systematically reduced using these two soluble electron acceptors, making S. woodyi a potential model bacterium for whole‐cell luminescence bioelectrochemical sensor applications.  相似文献   

18.
成熟小麦抗穗发芽能力与超弱发光关系的研究   总被引:10,自引:0,他引:10  
生物体的超弱发光表现与其本身的生理活动密切相关,利用超弱发光为指标,测定和比较了小麦不同品种在成熟时抗穗发芽的能力.为其进一步应用,解决农业实际问题提供方法和依据.  相似文献   

19.
The bacterial bioluminescence system is unusual because it is self-induced. In the late logarithmic phase of growth, upon the accumulation of an autoinducer, the synthesis of the components of the system is initiated. We were interested in determining what effect this burst of synthesis and activity has on cellular energy metabolism. The ATP pool of the luminous bacterium Beneckea harveyi was found to dip 10- to 20-fold during the luminescence period, while the respiration per unit cell mass (optical density) increased but by much less. The dip in the ATP pool did not occur in four different types of dark mutants, including one that was temperature conditional and another that was conditional upon added cyclic AMP for luminescence. However, it is neither the synthesis nor the activity of luciferase that is responsible for the ATP dip; the dip does not occur in certain dark "aldehyde" mutants which nevertheless synthesize normal levels of luciferase, whereas it does occur at 36 degrees C in a temperature-sensitive luciferase mutant which forms normal levels of inactive luciferase. Results with other aldehyde mutants implicate the pathway involved in the synthesis of the aldehyde factor with the ATP dip.  相似文献   

20.
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   

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