Spectra luminescence

The electroluminescence spectra of the single-layer devices are depicted in Figure 16-40. For all these OPV5s, EL spectra coincided with the solid-state photoluminescence spectra, indicating that the same excited states are involved in both PL and EL. The broad luminescence spectrum for Ooct-OPV5-CN" is attributed to excimer emission (Section 16.3.1.4). 

Fig. 1.5 Fluorescence emission spectrum of the luciferase-oxyluciferin complex in the same solution as in Fig. 1.4 (solid line), compared with the luminescence spectrum of firefly luciferin measured in glycylglycine buffer, pH 7.6 (dotted line). The former curve from Gates and DeLuca, 1975 the latter from Selinger and McElroy, 1960, both with permission from Elsevier.

Luminescence reaction (Viviani et al., 2002a) The luciferin-luciferase luminescence reaction was carried out in 0.1 M Tris-HCl, pH 8.0, containing 2mM ATP and 4mM Mg2+. Mixing luciferase with luciferin and ATP resulted in an emission of light with rapid onset and a kinetically complex decay. Further additions of fresh luciferase, after the luminescence has decayed to about 10% of its maximum value, resulted in additional luminescence responses similar to the initial one (Fig. 1.15). According to the authors, the repetitive light emission occurred in consequence of the inhibition of luciferase by a reaction product, as seen in the case of the firefly system (McElroy et al., 1953). The luminescence spectrum showed a peak at 487nm (Fig. 1.16). 

The bioluminescence reaction of Oplophorus is a typical luciferin-luciferase reaction that requires only three components luciferin (coelenterazine), luciferase and molecular oxygen. The luminescence spectrum shows a peak at about 454nm (Fig. 3.3.1). The luminescence is significantly affected by pH, salt concentration, and temperature. A certain level of ionic strength (salt) is necessary for the activity of the luciferase. In the case of NaCl, at least 0.05-0.1 M of the salt is needed for a moderate rate of light emission, and about 0.5 M for the maximum light intensity. 

Fig. 3.3.1 Luminescence spectrum of coelenterazine catalyzed by the luciferase of the decapod Oplophorus in 15 mM Tris-HCl, pH 8.3, containing 50 mM NaCl (solid line). For comparison, the luminescence catalyzed by the luciferase of the anthozoan sea pansy Renilla is shown with dashed line (in 25 mM Tris-HCl, pH 7.5, containing 0.1 M NaCl).

According to Charbonneau et al. (1985), aequorin is a single chain peptide consisting of 189 amino acid residues, with an unblocked amino terminal. The molecule contains three cysteine residues and three EF-hand Ca2+-binding domains. The absorption spectra of aequorin and BFP are shown in Fig. 4.1.3, together with the luminescence spectrum of aequorin and the fluorescence spectrum of BFP. 

Fig. 4.1.3 Absorption spectra of aequorin (A), spent solution of aequorin after Ca2+-triggered luminescence (B), and the chromophore of aequorin (C). Fluorescence emission spectrum of the spent solution of aequorin after Ca2+-triggered bioluminescence, excited at 340 nm (D). Luminescence spectrum of aequorin triggered with Ca2+ (E). Curve C is a differential spectrum between aequorin and the protein residue (Shimomura et al., 1974b) protein concentration 0.5 mg/ml for A and B, 1.0 mg/ml for C. From Shimomura and Johnson, 1976.

Fig. 4.1.16 Luminescence spectrum of aequorin triggered by Ca2+ (solid line /.max 465 nm), and the fluorescence spectra of Aequorea GFP excitation (dashed line A.max 400 nm and 477 nm) and emission (dash-dot line 7max 509 nm). The dotted line is the fluorescence excitation spectrum of GFP in the light organs, showing that 480 nm excitation peak is almost missing — an evidence showing that GFP in light organs exists in an aggregated form having a very low E value at 480 nm.

Renilla luciferase. The luciferase of Renilla reniformis has been purified and characterized by Karkhanis and Cormier (1971) and Matthews et al. (1977a). The purified luciferase has a molecular weight of 35,000, and catalyzes the luminescence reaction of coelenterazine. The luciferase-catalyzed luminescence is optimum at pH 7.4, at a temperature of 32°C, and in the presence of 0.5 M salt (such as NaCl or KC1). The luciferase has a specific activity of 1.8 x 1015 photons s"1mg"1, and a turnover number of 111/min. The luminescence spectrum shows a maximum at 480 nm. The absorbance A28O of a 0.1% luciferase solution is 2.1. The luciferase has a tendency to self-aggregate, forming higher molecular weight species of lower luminescence activities. 

Fig. 4.8.2 Comparison of the in vivo and in vitro luminescence of the photoproteins of Mnemiopsis sp. and Beroe ovata (A) in vitro luminescence spectra of mineopsin-1, -2, and berovin (B) in vivo luminescence spectrum of Mnemiopsis, (C) in vivo luminescence spectrum of Beroe. From Ward and Seliger, 1974b, with permission from the American Chemical Society.

Thus, the 2-methyl derivative of the imidazopyrazinone (above) dissolved in DMSO spontaneously emits blue light (A.max 450 nm) in the presence of air (Goto, 1968), like the 2-benzyl derivative (Amax 475 nm), the 2-methyl-6(p-hydroxyphenyl) derivative (MCLA 7max 468 nm), and coelenterazine (Amax 465 nm) under similar conditions (Fig. 5.3). The comparison of the luminescence spectra of these compounds shows that the 6-position substituent has little influence on the luminescence spectrum of coelenterazine derivatives, despite the apparent conjugation between the 6-phenyl ring and the imidazopyrazinone ring in the structures of MCLA and coelenterazine. 

Fig. 6.1.5 Fluorescence spectra of the purple protein (1-4) and the luminescence spectrum measured with Latia luciferin, luciferase and the purple protein (5 Xmax 536 nm). Excitation spectra (1) and (2) were measured with emission at 630 nm and 565 nm, respectively. Emission spectra (3) and (4) were measured with excitation at 285 nm and 380 nm, respectively. From Shimomura and Johnson, 1968c, with permission from the American Chemical Society.

Involvement of ATP in the luminescence. Tsuji (1985) found that homogenate of the light organs of W. scintillans emits light when ATP is added in the presence of Mg2+. The luminescence reaction has a sharp pH optimum at 8.8 (Fig. 6.3.3), and the luminescence spectrum shows a peak at 470 nm (Fig. 6.3.4). The luminescence reaction... 

Fig. 6.3.4 Luminescence spectrum of the Watasenia bioluminescence reaction measured with a crude extract of light organs that contain particulate matters, in chilled 0.1 M Tris-HCl buffer, pH 8.26, containing 1.5 mM ATP. From Tsuji, 2002, with permission from Elsevier.

Fig. 6.3.7 Luminescence spectrum of a homogenate of the luminous organ of Symplectoteuthis oualaniensis in the presence of 0.5 M KC1 (from Tsuji and Leisman, 1981). A homogenate suspension (1 ml) and 1MKC1 (1 ml), both made with 50 mM Tris-HCl, pH 7.6, containing 1 mM dithioerythritol, were mixed and the spectrum was measured 6 min after mixing. Note that the luminescence of the photoprotein symplectin isolated from the luminous organs showed a maximum at 470—480 nm (Takahashi and Isobe, 1993, 1994).

Fig. 7.1.5 Fluorescence spectra of purified Chaetopterus photoprotein (CPA) in 10 mM ammonium acetate, pH 6.7 (solid lines), and the bioluminescence spectrum of the luminous slime of Chaetopterus in 10 mM Tris-HCl, pH 7.2 (dashed line). Note that the luminescence spectrum of Chaetopterus photoprotein in 2 ml of 10 mM Tris-HCl, pH 7.2, containing 0.5 M NaCl, 5 pi of old dioxane and 2 pi of 10 mM FeSC>4 (Amax 453-455 nm) matched exactly with the fluorescence emission spectrum of the photoprotein. No significant change was observed in the fluorescence spectrum after the luminescence reaction.

Harvey (1952) demonstrated the luciferin-luciferase reaction with O. phosphorea collected at Nanaimo, British Columbia, Canada, and with O. enopla from Bermuda. McElroy (1960) partially purified the luciferin, and found that the luminescence spectrum of the luciferin-luciferase reaction of O. enopla is identical to the fluorescence spectrum of the luciferin (A.max 510 nm), and also that the luciferin is auto-oxidized by molecular oxygen without light emission. Further investigation on the bioluminescence of Odontosyllis has been made by Shimomura etal. (1963d, 1964) and Trainor (1979). Although the phenomenon is well known, the chemical structure of the luciferin and the mechanism of the luminescence reaction have not been elucidated. 

Fig. 7.2.6 (A) Luminescence spectrum of Odontosyllis luciferin-luciferase reac-...

Fig. 7.3.2 Comparison between the in vivo luminescence spectrum of a freshly exuded slime of Diplocardia longa and the in vitro luminescence spectrum measured with partially purified preparations of Diplocardia luciferin and luciferase. Reproduced from Bellisario et al., 1972, with permission from the American Chemical Society. Note that the in vitro emission maximum shifts to 490 nm when a sample of pure luciferin is used (Ohtsuka et al., 1976).

Fig. 7.4.2 Luminescence spectrum of a solution of the photoprotein polynoidin. Light emission was initiated by the additions of H2O2 (final cone. 3mM) and Fe2+ (final cone. 0.1 mM). From Nicolas et al., 1982, with permission form the American Society for Photobiology.

Fig. 9.9 Luminescence spectrum of a young fruiting body of Fanellus stipticus (1) the chemiluminescence spectra of PM-1 in the presence of CTAB (2) hexadecanoyl-choline iodide (3) and tetradecanoylcholine chloride (4). Chemiluminescence was elicited with Fe2+ and H2O2 in 50mM Tris buffer, pH 8.0, containing 0.18mM EDTA.

The absorption spectrum of the photoprotein showed a small peak (Xmax 423 nm, with a shoulder at about 450 nm) in addition to the protein peak at 280nm (Fig. 10.1.2). The peak at 423nm decreased slightly upon the FI202-triggered luminescence reaction. The photoprotein is fluorescent in greenish-blue (emission A.max 482 nm), which coincides exactly with the luminescence spectrum of the photoprotein... 

Fig. 10.1.3 Fluorescence excitation and emission spectra (solid lines) and H2O2-triggered luminescence spectrum (dashed line) of Ophiopsila photoprotein (Shimomura, 1986b, revised). The dotted line indicates the in vivo bioluminescence spectrum of Ophiopsila californica plotted from the data reported by Brehm and Morin (1977).

Davenport et al. (1952) were unsuccessful in their attempts to restore the luminescence of the filtered aqueous extract of Luminodesmus. Hastings and Davenport (1957) saw a weak luminescence in their filtered aqueous extracts made from the acetone powder of the millipedes. They found that the luminescence is dependent on pH, with an optimum at about pH 8.9, and that the light intensity could be increased by 10-30% by adding ATP. Hastings and Davenport also measured the luminescence spectrum of live animals, finding an emission peak at 495 nm. 

Fig. 10.S.3 Luminescence spectrum of the light emitted from freeze-dried, powdered specimens of the ascidian Clavelina miniata upon addition of water. The same luminescence spectrum was obtained when living specimens were stimulated. From Chiba et ai, 1998, with permission from John Wiley Sons Ltd.

Euphausiid bioluminescence, 71-81 effect of pH, 72, 73 effects of temperature and salts, 80 luminescence spectrum, 77 Euprymna, 334 Eustomias, 338 Eusyllis, 335... 

Laetmogone, 301, 337 Latnpadena, 163, 339 Lampito, 216, 234, 335 Lampteroflavin, 270 Lampteromyces, 267, 270 Lampyridae, 1, 2 See also Fireflies distribution, 2 morphology, 2 Lampyris, 2, 337 Latia bioluminescence, 189 activators and inhibitors, 189 light emitter, 191 luminescence spectrum, 192 reaction scheme, 190 Latia luciferase, 183-189, 343 assay, 184... 

Oplopborus luminescence, 82-87 effects of pH and temperature, 83-86 luminescence spectrum, 84 mechanism, 85-87 quantum yield of coelenterazine, 85 Orfelia, 2, 27, 337... 

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