Photochemical-like effects in DNA caused by enzynically energized triplet carbonyl cmpounds

Faljoni, Adelaide; Haun, Marcela; Hoffmann, Maria E.; Meneghini, Rogério; Durán, Nélson; Cilento, Giuseppe

doi:10.1016/0006-291x(78)91595-4

Cited by 32 publications

(5 citation statements)

References 23 publications

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“…This figure depicts the formation of products of the formylkynurenine type by irradiation of tryptophan at 280 nm for 47 h (Borkman, 1977) or by 10-min exposure to the propanal-HRP-02 system, which appears to generate triplet acetaldehyde (Haun et al, 1980). Here, as in other systems studied in these laboratories (Rivas-Suárez et al, 1981;Faljoni et al, 1978), a brief exposition to our enzymic reactions which generate triplet species produces photochemical-like effects which normally require prolonged irradiation.…”

Section: Resultsmentioning

confidence: 94%

“…A study of the quenching effect of oxygen and of the sórbate ion supports this interpretation (Bechara et al, 1979). Despite protection, however, this triplet acetone can transfer its energy by a long-range mechanism, not yet fully understood (Haun et al, 1978;Augusto & Cilento, 1979;Cilento, 1980a,b;, and promote photochemical processes ("photobiochemistry in the dark") (Faljoni et al, 1978;Meneghini et al, 1978;Durán et al, 1978; was measured with a Yellow Springs Model 53 oxygen monitor. Absorption spectra were recorded on Zeiss-DMR-21 and DMR-10 recording spectrophotometers.…”

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confidence: 90%

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Quenching of enzyme-generated acetone phosphorescence by indole compounds: stereospecific effects of D- and L-tryptophan. Photochemical-like effects

Rivas‐Suárez¹,

Cilento²

1981

Biochemistry

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Indole compounds efficiently quench the acetone phosphorescence observed during the horseradish peroxidase catalyzed aerobic oxidation of isobutyraldehyde. Different types of Stern-Volmer plots are observed: linear, linear with two slopes, and downward- and upward-curved plots. The complexity probably stems from the operation of both dynamic and static quenching, coupled with different efficiencies of quenching of various acetone triplet populations. Binding to the enzyme may also occur, especially in the case of L-tryptophan. The different Stern-Volmer behavior of D- and L-tryptophan fully confirms that the acetone triplet is generated within the enzyme and not free in solution. This chiral discrimination toward an enzymically generated electronically excited species is novel. It is tentatively postulated that a long-range triplet-triplet exciton transfer occurs; the excited triplet indole then undergoes photochemical-like alterations.

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Section: Resultsmentioning

confidence: 94%

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confidence: 90%

Quenching of enzyme-generated acetone phosphorescence by indole compounds: stereospecific effects of D- and L-tryptophan. Photochemical-like effects

Rivas‐Suárez¹,

Cilento²

1981

Biochemistry

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“…The collaboration between Waldemar Adam and Giuseppe Cilento, along with results obtained by Angelo Lamola at Bell Labs, produced outstanding insights on the chemical modification of DNA by 1,2‐dioxetanes . Adjacent pyrimidine residues in DNA are subject to dimerization via a [2 + 2] cycloaddition, ie , Paternò‐Büchi reaction, not only when DNA is exposed UV light but also coupled with 1,2‐dioxetane thermolysis that produce oxidized guanosine nucleobases (8‐hydroxy‐2'‐desoxyguanosine) as well …”

Section: The (Bio)chemistry Of Four‐membered Ring Peroxidesmentioning

confidence: 99%

Four‐membered cyclic peroxides: Carriers of chemical energy

Bastos

Farahani

Bechara

et al. 2017

J of Physical Organic Chem

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Four-membered cyclic peroxides are high-energy compounds often associated to cold light emission, but whose chemical and biological roles are still matters of debate. The often-dangerous synthesis of 1,2-dioxetanes, achieved around 50 years ago, has been mastered over the years to a point where some derivatives are commercially available. This fact does not imply that 1,2-dioxetanes can be conveniently prepared in the gram scale or that the synthesis of analogous 1,2-dioxetanones and the elusive 1,2-dioxetanedione are simple. Important questions on the mechanism of chemiluminescence and bioluminescence reactions are under experimental and theoretical scrutiny. The available data have contributed to relate structural and medium effects to the quantum efficiency of these compounds to produce excited states. Consequently, such peroxides have been suggested to produce biologically relevant electronically excited species in vivo in the absence of light. The connection of this hypothesis with melanin-mediated photodamage in the dark has renewed the interest in such cyclic peroxides. This review gives some insight on the synthesis, chemiluminescence mechanism, and biological relevance of 1,2-dioxetanes, 1,2-dioxetanones, and 1,2-dioxetanedione and provides practical protocols for those interested in engaging this field.

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“…Earlier, we reported that enzyme-generated excited species are able to excite a series of acceptors, including macromolecules such as DNA (Meneghini et al, 1978;Faljoni et al, 1978) and RNA . In the case of macromolecules, the occurrence of energy transfer was inferred.…”

Section: Resultsmentioning

confidence: 99%

Excited indole-3-aldehyde from the peroxidase-catalyzed aerobic oxidation of indole-3-acetic acid. Reaction with and energy transfer to transfer ribonucleic acid

Mello¹,

Toledo²,

Haun³

et al. 1980

Biochemistry

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The horseradish peroxidase catalyzed aerobic oxidation of the auxin indole-3-acetic acid generates triplet indole-3-aldehyde in high yield. The excited species is quenched by oxygen with formation of singlet oxygen, which is responsible for the observed photon emission and can be trapped by suitable agents. tRNA dramatically enhances the emission as a result of energy transfer from triplet indole-3-aldehyde to a 4-thiouridine group in tRNA. Triplet indole-3-aldehyde also adds covalently to tRNA. The results provide a possible mechanism for the auxin-tRNA interaction in vivo.

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Photochemical-like effects in DNA caused by enzynically energized triplet carbonyl cmpounds

Cited by 32 publications

References 23 publications

Quenching of enzyme-generated acetone phosphorescence by indole compounds: stereospecific effects of D- and L-tryptophan. Photochemical-like effects

Quenching of enzyme-generated acetone phosphorescence by indole compounds: stereospecific effects of D- and L-tryptophan. Photochemical-like effects

Four‐membered cyclic peroxides: Carriers of chemical energy

Excited indole-3-aldehyde from the peroxidase-catalyzed aerobic oxidation of indole-3-acetic acid. Reaction with and energy transfer to transfer ribonucleic acid

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