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Chemiluminescence and Bioluminescence

Chemiluminescence and bioluminescence are defined as processes in which light is generated during chemical or biological reactions, i.e., exothermic reactions in which part of the reaction energy is converted into photons. In chemiluminescence, an educt molecule is converted to the final stable product upon decay of an unstable chemical intermediate that only exists in an excited electronic state [160, 161]. Bioluminescence includes reactions of photoproteins such as aequorin and of enzymes such as the luciferases (see below). [Pg.642]

Glow luminescence techniques have been used extensively with luciferases as reporter genes in cell-based assays. An overview of such assays is given in Section 10.3.2 Reporter Assays below. Luciferases are enzymes which catalyze bio-luminescent reactions. Two forms are used as reporters, one originating from the firefly (firefly luciferase) and the other from Rmilla (Renilla luciferase). Due to their different origins, the enzyme structures and their respective substrates are quite different While Rmilla luciferase catalyzes the oxidation of coelenterazine, the substrate of firefly luciferase is the beetle luciferin, which is oxidized in the presence of ATP and Mg as depicted in Fig. 17. [Pg.642]

The distinct difference in substrate makes it possible to use both luciferase reporters simultaneously in one assay, as in Promega s Dual-Ludferase Reporter (DLR ) assay system [162]. [Pg.642]

Aequorin is a Ca -sensitive, bioluminescent protein complex that was originally isolated from the jellyfish Aequorea victoria [166]. The protein complex is assembled in the presence of molecular oxygen from the protein apoaequorin and its cofactor, the luminophore coelenterazine [167] (see Fig. 18). The binding of Ca ions induces a conformational change in the complex, resulting in the oxidation of coelenterazine and a subsequent emission of blue light in the wavelength [Pg.643]

The purification of aequorin from jellyfish is laborious and has a low yield - two tons of jellyfish are needed to obtain about 125 mg of protein [168]. Today, aequorin can be produced by recombinantly expressing apoaequorin in E. coli followed by in vitro reconstitution with coelenterazine [13]. [Pg.644]

There is another artefact that can arise with concentrated samples, and this is the reabsorption of emission light by the sample itself. Light which is emitted at the centre of the cell must travel through a pathlength of a few mm of the sample, and absorption will take place in the wavelength region of overlap of the emission and absorption spectra. This problem can be serious when the Stoke s shift of these spectra is small. Reabsorption then results in an apparent red shift of the emission maximum with increasing concentration. [Pg.235]

The short lifetimes of excited diaryl polyene singlet states precludes the equilibration of conformers following excitation and, as a result, the conformational distribution in the ground state controls the product distribution. Because the absorption spectra of different conformers usually differ, this results in an excitation-wavelength dependence of the product distribution (NEER principle 501 cf. Section 6.1.1 and Case Study 6.3). [Pg.223]

The energy requirement is an obstacle to the physical characterization of chemiluminescent compounds because the availability of a reaction of high exothermicity renders most such reagents unstable. They are usually generated in situ by mixing stable precursors with appropriate reagents. The observation of blue chemiluminescence from a solution of oxalyl chloride and hydrogen peroxide was first reported in 1963,510 now well [Pg.223]

The majority of bioluminescent organisms live in the ocean, but there are many terrestrial forms, notably beetles, that exploit bioluminescence. The bioluminescence of fireflies [Pg.224]

The pK of phenalene ionizing to its anion 4 (Case Study 4.1) is about 20. The first absorption band of phenalene lies at vq o 2.9 pm Predict the acidity constant of phenalene in the lowest excited singlet state. [p fa = — 1] [Pg.225]

Identify the symmetry point groups of formaldehyde [C2v, ammonia [C3J, phenol [CJ, gyloxal C2h and allene [D2hl- [Pg.226]


The release of a photon following thermal excitation is called emission, and that following the absorption of a photon is called photoluminescence. In chemiluminescence and bioluminescence, excitation results from a chemical or biochemical reaction, respectively. Spectroscopic methods based on photoluminescence are the subject of Section lOG, and atomic emission is covered in Section lOH. [Pg.423]

Analytical Applications. Chemiluminescence and bioluminescence are useful in analysis for several reasons. (/) Modem low noise phototubes when properly instmmented can detect light fluxes as weak as 100 photons/s (1.7 x 10 eins/s). Thus luminescent reactions in which intensity depends on the concentration of a reactant of analytical interest can be used to determine attomole—2eptomole amounts (10 to 10 mol). This is especially useful for biochemical, trace metal, and pollution control analyses (93,260—266) (see Trace and residue analysis). (2) Light measurement is easily automated for routine measurements as, for example, in clinical analysis. [Pg.274]

Chemiluminescence and bioluminescence are also used in immunoassays to detect conventional enzyme labels (eg, alkaline phosphatase, P-galactosidase, glucose oxidase, glucose 6-phosphate dehydrogenase, horseradish peroxidase, microperoxidase, xanthine oxidase). The enhanced chemiluminescence assay for horseradish peroxidase (luminol-peroxide-4-iodophenol detection reagent) and various chemiluminescence adamantyl 1,2-dioxetane aryl phosphate substrates, eg, (11) and (15) for alkaline phosphatase labels are in routine use in immunoassay analyzers and in Western blotting kits (261—266). [Pg.275]

One is the concerted decomposition of a dioxetanone structure that is proposed for the chemiluminescence and bioluminescence of both firefly luciferin (Hopkins et al., 1967 McCapra et al., 1968 Shimomura et al., 1977) and Cypridina luciferin (McCapra and Chang, 1967 Shimomura and Johnson, 1971). The other is the linear decomposition mechanism that has been proposed for the bioluminescence reaction of fireflies by DeLuca and Dempsey (1970), but not substantiated. In the case of the Oplopborus bioluminescence, investigation of the reaction pathway by 180-labeling experiments has shown that one O atom of the product CO2 derives from molecular oxygen, indicating that the dioxetanone pathway takes place in this bioluminescence system as well (Shimomura et al., 1978). It appears that the involvement of a dioxetane intermediate is quite widespread in bioluminescence. [Pg.87]

Based on the available knowledge on the chemiluminescence and bioluminescence reactions of various luciferins (firefly, Cypridina, Oplophorus and Renilla), the luminescence reaction of coelenterazine is considered to proceed as shown in Fig. 5.4 (p. 171). The reaction is initiated by the binding of O2 at the 2-position of the coelenterazine molecule, giving a peroxide. The peroxide then forms a four-membered ring dioxetanone, as in the case of the luminescence... [Pg.168]

Hori, K., Wampler, J. E., Matthews, J. C., and Cormier, M. J. (1973). Identification of the product excited states during the chemiluminescent and bioluminescent oxidation of Renilla (sea pansy) luciferin and certain of its analogs. Biochemistry 12 4463-4468. [Pg.404]

Lee, J., and Seliger, H. H. (1965). Absolute spectral sensitivity of phototubes and the application to the measurement of the absolute quantum yields of chemiluminescence and bioluminescence. Photochem. Photobiol. 4 1015-1048. [Pg.413]

Stanley, P. E. (1992). A survey of more than 90 commercially available luminometers and imaging devices for low-light measurements of chemiluminescence and bioluminescence, including instruments for manual, automatic and specialized operation, for HPLC, LC, GLC and microtiter plates. Part I descriptions. T. Biolumin. Chemilumin. 7 77-108. [Pg.439]

Argus Laboratories Ltd. Chemiluminescent and bioluminescent products Berthold. Luminescence assays http / / www.berthold-online.com/ http //www.net-escape.co.uk/business/argus/... [Pg.62]

Figure 1 Scheme of chemiluminescent and bioluminescent light emission. [Pg.248]

The advantages of detecting cDNA probes by chemiluminescence and bioluminescence include high sensitivity and simple protocols, using either manual film... [Pg.564]

Methods based on chemiluminescent and bioluminescent labels are another area of nonisotopic immunoassays that continue to undergo active research. Most common approaches in this category are the competitive binding chemiluminescence immunoassays and the immunochemiluminometric assays. Chemiluminescence and heterogenous chemiluminescence immunoassays have been the subject of excellent reviews (91, 92). Detection in chemiluminescence immunoassays is based on either the direct monitoring of conjugated labels, such as luminol or acridinium ester, or the enzyme-mediated formation of luminescent products. Preparation of various derivatives of acridinium esters has been reported (93, 94), whereas a variety of enzyme labels including firefly or bacterial luciferase (70), horseradish peroxidase (86, 98), and alkaline phosphatase are commercially available. [Pg.691]

Kricka, L. J. and Thorpe, G H G. (1986) Photographic detection of chemiluminescent and bioluminescent reactions. Methods Enzymol 133,404-420... [Pg.206]


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