Interaction and photobinding between 8-methoxypsoralen and thymine

Omar, Salama; Eriksson, Leif A.

doi:10.1016/j.cplett.2009.02.010

Cited by 9 publications

(9 citation statements)

References 31 publications

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“…This was recently explained by an efficient photoinduced electron transfer reaction from guanine to intercalated AMT inside either DNA (203,204) or human telomeric Gquadruplex (205) as shown by femtosecond transient absorption spectroscopy. Further information on excited psoralen transients, photobinding of bifunctional furocoumarins to thymine and the reactivity of the resulting furan-and pyrone-side monoadducts was gained from quantum chemistry studies (206)(207)(208). The inability for pyrone-side adduct of 8-MOP to thymine to be converted into interstrand cross-links was explained by the blueshift of their S 1 excitation energy with respect to isolated photosensitizer, thus preventing any further UVA-mediated reaction (207,208).…”

Section: Mono-and Intrastrand Psoralen-dna Photoadductsmentioning

confidence: 99%

“…Further information on excited psoralen transients, photobinding of bifunctional furocoumarins to thymine and the reactivity of the resulting furan-and pyrone-side monoadducts was gained from quantum chemistry studies (206)(207)(208). The inability for pyrone-side adduct of 8-MOP to thymine to be converted into interstrand cross-links was explained by the blueshift of their S 1 excitation energy with respect to isolated photosensitizer, thus preventing any further UVA-mediated reaction (207,208). It was shown from ONIOM and hybrid DFT calculations that the formation of furan-and pyrone-side monoadducts to thymine involves a psoralens triplet excited state as the precursor of a biradical.…”

Section: Mono-and Intrastrand Psoralen-dna Photoadductsmentioning

confidence: 99%

See 1 more Smart Citation

Photosensitization Reactions of Biomolecules: Definition, Targets and Mechanisms

Baptista

Cadet

Greer

et al. 2021

Photochem & Photobiology

106

144

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Photosensitization reactions have been demonstrated to be largely responsible for the deleterious biological effects of UV and visible radiation, as well as for the curative actions of photomedicine. A large number of endogenous and exogenous photosensitizers, biological targets and mechanisms have been reported in the past few decades. Evolving from the original definitions of the type I and type II photosensitized oxidations, we now provide physicochemical frameworks, classifications and key examples of these mechanisms in order to organize, interpret and understand the vast information available in the literature and the new reports, which are in vigorous growth. This review surveys in an extended manner all identified photosensitization mechanisms of the major biomolecule groups such as nucleic acids, proteins, lipids bridging the gap with the subsequent biological processes. Also described are the effects of photosensitization in cells in which UVA and UVB irradiation triggers enzyme activation with the subsequent delayed generation of superoxide anion radical and nitric oxide. Definitions of photosensitized reactions are identified in biomolecules with key insights into cells and tissues.

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Section: Mono-and Intrastrand Psoralen-dna Photoadductsmentioning

confidence: 99%

Section: Mono-and Intrastrand Psoralen-dna Photoadductsmentioning

confidence: 99%

Photosensitization Reactions of Biomolecules: Definition, Targets and Mechanisms

Baptista

Cadet

Greer

et al. 2021

Photochem & Photobiology

106

144

View full text Add to dashboard Cite

show abstract

“…The mechanism of this photoaddition was addressed by steady-state [11] and time-resolved spectroscopy [16][17][18] as well as quantum chemistry [19][20][21][22]. In a recent study, we traced the photo-addition of psoralen to DNA in real-time [23].…”

Section: Introductionmentioning

confidence: 99%

Tracing the Photoaddition of Pharmaceutical Psoralens to DNA

et al. 2020

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The psoralens 8-methoxypsoralen (8-MOP), 4,5′,8-trimethylpsoralen (TMP) and 5-methoxypsoralen (5-MOP) find clinical application in PUVA (psoralen + UVA) therapy. PUVA treats skin diseases like psoriasis and atopic eczema. Psoralens target the DNA of cells. Upon photo-excitation psoralens bind to the DNA base thymine. This photo-binding was studied using steady-state UV/Vis and IR spectroscopy as well as nanosecond transient UV/Vis absorption. The experiments show that the photo-addition of 8-MOP and TMP involve the psoralen triplet state and a biradical intermediate. 5-MOP forms a structurally different photo-product. Its formation could not be traced by the present spectroscopic technique.

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“…The same strategy was successfully employed in previous work on photoinduced cycloadditions in pyrimidine bases. [20][21][22]34 The calculations were performed in two steps. First the thermal reaction pathways on the different monoadducts cycloaddition were explored.…”

Section: Methods and Computational Detailsmentioning

confidence: 99%

Computational study of khellin excited states and photobinding to DNA

Omar

Eriksson

2009

Photochem Photobiol Sci

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A theoretical investigation of the formation and spectroscopic properties of the furan and pyrone monoadducts between the photosensitizer khellin and DNA base thymine is reported. The thermal reaction pathways involve very high barriers, whereas the excited state surfaces display low barriers in regions leading to the ground state TS structures and potential wells at the ground state TS geometries. Computed UV absorption spectra are interpreted with the support of molecular orbital calculations, and the role of solvent effects on the spectra is discussed. The red-shift in the khellin spectra upon intercalation in DNA is excellently reproduced by the computational methodology, as is the solvent induced spectral shift. The data also provides an explanation to why khellin predominantly forms furan monoadducts in DNA, as opposed to the closely related psoralen compounds.

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Interaction and photobinding between 8-methoxypsoralen and thymine

Cited by 9 publications

References 31 publications

Photosensitization Reactions of Biomolecules: Definition, Targets and Mechanisms

Photosensitization Reactions of Biomolecules: Definition, Targets and Mechanisms

Tracing the Photoaddition of Pharmaceutical Psoralens to DNA

Computational study of khellin excited states and photobinding to DNA

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