Transient and stationary spectroscopy of cytochrome c: ultrafast internal conversion controls photoreduction.


:Photoreduction of cytochrome c (Cyt c) has been reinvestigated using femtosecond-to-nanosecond transient absorption and stationary spectroscopy. Femtosecond spectra of oxidized Cyt c, recorded in the probe range 270-1000 nm, demonstrate similar evolution upon 266 or 403 nm excitation: an ultrafast 0.3 ps internal conversion followed by a 4 ps vibrational cooling. Late transient spectra after 20 ps, from the cold ground-state chromophore, reveal a small but measurable signal from reduced Cyt c. The yield phi for Fe3+-->Fe2+ photoreduction is measured to be phi(403) = 0.016 and phi(266) = 0.08 for 403 and 266 nm excitation. These yields lead to a guess of the barrier E(f)(A) = 55 kJ mol(-1) for thermal ground-state electron transfer (ET). Nanosecond spectra initially show the typical absorption from reduced Cyt c and then exhibit temperature-dependent sub-microsecond decays (0.5 micros at 297 K), corresponding to a barrier E(A)(b) = 33 kJ mol(-1) for the back ET reaction and a reaction energy DeltaE = 22 kJ mol(-1). The nanosecond transients do not decay to zero on a second time scale, demonstrating the stability of some of the reduced Cyt c. The yields calculated from this stable reduced form agree with quasistationary reduction yields. Modest heating of Cyt c leads to its efficient thermal reduction as demonstrated by differential stationary absorption spectroscopy. In summary, our results point to ultrafast internal conversion of oxidized Cyt c upon UV or visible excitation, followed by Fe-porphyrin reduction due to thermal ground-state ET as the prevailing mechanism.


Photochem Photobiol


Löwenich D,Kleinermanns K,Karunakaran V,Kovalenko SA




Has Abstract


2008-01-01 00:00:00














  • UV exposure alters respiratory allergic responses in mice.

    abstract::We have tested the hypothesis that exposure to ultraviolet light would inhibit T helper-1 (Th1) responses and stimulate T helper-2 (Th2) responses, and that thus in a mouse model of allergic (i.e. extrinsic) asthma (using ovalbumin [OVA] as the allergen) increased symptoms would be observed, while in a model of Th1-de...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Van Loveren H,Boonstra A,Van Dijk M,Fluitman A,Savelkoul HF,Garssen J

    更新日期:2000-08-01 00:00:00

  • Computational analysis of the oxygen addition at the C4a site of reduced flavin in the bacterial luciferase bioluminescence reaction.

    abstract::The energetic characteristics of selected reaction steps in the bacterial luciferase-catalyzed luminescence reaction were examined by computation using the MNDO-PM3 method. Specifically, a three-step model was proposed to account for the reaction between oxygen and reduced riboflavin 5'-phosphate (1,5H2-FMN) to genera...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Wada N,Sugimoto T,Watanabe H,Tu SC

    更新日期:1999-07-01 00:00:00

  • Advanced glycation endproducts induce photocrosslinking and oxidation of bovine lens proteins through type-I mechanism.

    abstract::Advanced glycation endproducts (AGEs) have been suggested as photosensitizers that are capable of mediating eye lens photo-damage during aging. In the present work, we investigate the photo-crosslinking and oxidation of bovine lens proteins sensitized by AGEs, with special regard to low oxygen conditions. A mechanisti...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Fuentealba D,Friguet B,Silva E

    更新日期:2009-01-01 00:00:00

  • Generation of free radicals by emodic acid and its [D-Lys6]GnRH-conjugate.

    abstract::In an attempt to develop an efficient chemotherapeutic agent targeted at malignant cells that express receptors to gonadotropin releasing hormone (GnRH) we coupled [D-Lys6]GnRH covalently to an emodin derivative, i.e. emodic acid (Emo) to yield [D-Lys6(Emo)]GnRH. Emodin is a naturally occurring anthraquinone which is ...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Rahimipour S,Bilkis I,Péron V,Gescheidt G,Barbosa F,Mazur Y,Koch Y,Weiner L,Fridkin M

    更新日期:2001-08-01 00:00:00

  • Cancer Cell-targeted and Activatable Photoimmunotherapy Spares T Cells in a 3D Coculture Model.

    abstract::Photodynamic therapy (PDT) is an established therapeutic modality that uses nonionizing near-infrared light to activate photocytotoxicity of endogenous or exogenous photosensitizers (PSs). An ongoing avenue of cancer research involves leveraging PDT to stimulate antitumor immune responses; however, these effects appea...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Kercher EM,Nath S,Rizvi I,Spring BQ

    更新日期:2020-03-01 00:00:00

  • Identification of ROS produced by photodynamic activity of chlorophyll/cyclodextrin inclusion complexes.

    abstract::Photodynamic therapy (PDT) is a way of treating malignant tumors and hyperproliferative diseases. It is based on the use of photosensitizer, herein the chlorophyll a (chl a), and a light of an appropriate wavelength. The interaction of the photosensitizer (PS) with the light produces reactive oxygen species (ROS), pow...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Cellamare BM,Fini P,Agostiano A,Sortino S,Cosma P

    更新日期:2013-03-01 00:00:00

  • Ligand-dependent interaction of ruthenium(II) polypyridyl complexes with DNA probed by emission spectroscopy.

    abstract::The nature of the interaction in buffered aqueous solution of several homo and heteroleptic ruthenium(II) polypyridyl complexes containing 2,2'-bipyridine (bpy), 2,2'-bipyrazine (bpz), 1,10-phenanthroline (phen), 4,7-diphenyl-1,10-phenanthroline (dip), 3,4,7,8-tetramethyl-1,10-phenanthroline (tmp), 1,4,5,8-tetraazaphe...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Kirsch-De Mesmaeker A,Orellana G,Barton JK,Turro NJ

    更新日期:1990-09-01 00:00:00

  • Distance-dependent fluorescence quenching of tryptophan by acrylamide.

    abstract::We used GHz frequency-domain fluorometry to investigate the time-dependent intensity decays of N-acetyl-L-trytophanamide (NATA) when collisionally quenched by acrylamide in propylene glycol at 20 degrees C. The intensity decays of NATA became increasingly heterogeneous in the presence of acrylamide. The NATA intensity...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Lakowicz JR,Zelent B,Gryczynski I,Kuśba J,Johnson ML

    更新日期:1994-09-01 00:00:00

  • Second Rhagophthalmid Luciferase Cloned from Chinese Glow-worm Menghuoius giganteus (Rhagophthalmidae: Elateroidea).

    abstract::The pH-insensitive beetle luciferases cloned from Rhagophthalmidae, Phengodidae, and Elateridae exhibit great potential application as reporter assays for monitoring gene expression. At present, however, only one luciferase has been reported from the enigmatic and predominantly Asian distributed luminous family Rhagop...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Liu GC,Dong ZW,Hou QB,He JW,Zhao RP,Wang W,Li XY

    更新日期:2020-01-01 00:00:00

  • Chronic low-dose UVA irradiation induces local suppression of contact hypersensitivity, Langerhans cell depletion and suppressor cell activation in C3H/HeJ mice.

    abstract::It has previously been demonstrated that chronic low-dose solar-simulated UV radiation could induce both local and systemic immunosuppression as well as tolerance to a topically applied hapten. In this study, we have used a chronic low-dose UV-irradiation protocol to investigate the effects of UVA on the skin immune s...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Bestak R,Halliday GM

    更新日期:1996-12-01 00:00:00

  • Molecular evolution of the Ca(2+)-binding photoproteins of the Hydrozoa.

    abstract::Alignment of the primary structures of the hydrozoan photoproteins, aequorin, mitrocomin, clytin and obelin showed very strong amino acid sequence identities. The Ca(2+)-binding sites of the proteins were found to be highly conserved. The Ca(2+)-binding sites were also homologous to the Ca(2+)-binding sites of other C...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Tsuji FI,Ohmiya Y,Fagan TF,Toh H,Inouye S

    更新日期:1995-10-01 00:00:00

  • Membrane damage efficiency of phenothiazinium photosensitizers.

    abstract::Structure-activity relationships have been widely reported for porphyrin and phthalocyanine photosensitizers, but not for phenothiazinium derivatives. Here, four phenothiazinium salts (methylene blue, toluidine blue O, 1,9-dimethyl methylene blue and the pentacyclic derivative DO15) were used to investigate how the ab...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Bacellar IO,Pavani C,Sales EM,Itri R,Wainwright M,Baptista MS

    更新日期:2014-07-01 00:00:00

  • mTHPC-mediated photodynamic treatment up-regulates the cytokines VEGF and IL-1alpha.

    abstract::Photodynamic therapy (PDT) of cancer induces oxidative stress, which intervenes in the expression of cytokines by tumor cells. The cytokines might have either a positive or a negative impact on tumor eradication. Here, we studied the expression of cytokines vascular endothelial growth factor (VEGF) and interleukin-1al...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Dabkeviciene D,Sasnauskiene A,Leman E,Kvietkauskaite R,Daugelaviciene N,Stankevicius V,Jurgelevicius V,Juodka B,Kirveliene V

    更新日期:2012-03-01 00:00:00

  • Chaetopterus variopedatus Bioluminescence: A Review of Light Emission within a Species Complex.

    abstract::Chaetopterus variopedatus has been studied for over a century in terms of its physiology, ecology and life history. One focus of research is on its intrinsic bioluminescent emissions, which can be observed as a blue light emitted from the extremities of individual body segments, or as a secreted mucus. Even though res...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章,评审


    authors: Mirza JD,Migotto ÁE,Yampolsky IV,de Moraes GV,Tsarkova AS,Oliveira AG

    更新日期:2020-07-01 00:00:00

  • UVA exposure affects UVB and cis-urocanic acid-induced systemic suppression of immune responses in Listeria monocytogenes-infected Balb/c mice.

    abstract::Ultraviolet radiation can inhibit immune responses locally as well as systemically. Such effects have been measured in animals and humans exposed to ultraviolet B (wavelength 280-315 nm) (UVB) and ultraviolet A (315-400 nm) (UVA). The precise wavelength dependence is important for the identification of possible molecu...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Garssen J,de Gruijl F,Mol D,de Klerk A,Roholl P,Van Loveren H

    更新日期:2001-04-01 00:00:00

  • Enhanced UV-B radiation increases glyphosate resistance in velvetleaf (Abutilon theophrasti).

    abstract::Depletion of the ozone layer leads to increasing UV-B radiation on the earth's surface, which may affect weeds and their responses to herbicides. However, the effect of increased UV-B radiation on weeds and the interaction of weeds and herbicides are still obscure. The objective of this study was to compare glyphosate...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Yin L,Zhang M,Li Z,Duan L,Wang S

    更新日期:2012-11-01 00:00:00

  • Fluence Rate Determines PDT Efficiency in Breast Cancer Cells Displaying Different GSH Levels.

    abstract::Photodynamic therapy (PDT) appears as a promising alternative in the treatment of breast cancer since it can be highly effective in curing cancer while preserving normal tissue. However, predicting outcomes in PDT still constitutes a great challenge. One of the parameters that are usually empirically determined is the...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Dos Santos AF,de Almeida DRQ,Terra LF,Wailemann RAM,Gomes VM,Arini GS,Ravagnani FG,Baptista MS,Labriola L

    更新日期:2020-05-01 00:00:00

  • Quenching enhancement of the singlet excited state of pheophorbide-a by DNA in the presence of the quinone carboquone.

    abstract::Changes in the emission fluorescence intensity of pheophorbide-a (PHEO) in the presence of carboquone (CARBOQ) were used to obtain the association constant, the number of CARBOQ molecules interacting with PHEO, and the fluorescence quantum yield of the complex. Excitation spectra of mixtures of PHEO and CARBOQ in etha...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Díaz-Espinosa Y,Crespo-Hernández CE,Alegría AE,García C,Arce R

    更新日期:2011-03-01 00:00:00

  • Proton uptake of rhodobacter capsulatus reaction center mutants modified in the primary quinone environment.

    abstract::Flash-induced absorbance spectroscopy was used to analyze the proton uptake and electron transfer properties of photosynthetic reaction centers (RC) of Rhodobacter capsulatus that have been genetically modified near the primary quinone electron acceptor (Q(A)). M246Ala and M247Ala, which are symmetry-related to the po...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Tandori J,Miksovska J,Valerio-Lepiniec M,Schiffer M,Maróti P,Hanson DK,Sebban P

    更新日期:2002-02-01 00:00:00

  • Mechanisms of ultraviolet light-induced pigmentation.

    abstract::Work in the past 8 years, particularly in the past 1-2 years, has greatly expanded our understanding of the mechanisms by which ultraviolet irradiation stimulates melanogenesis in the skin. A direct effect of UV photons on DNA results in up-regulation of the gene for tyrosinase, the rate-limiting enzyme in melanin syn...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章,评审


    authors: Gilchrest BA,Park HY,Eller MS,Yaar M

    更新日期:1996-01-01 00:00:00

  • Pomegranate fruit extract modulates UV-B-mediated phosphorylation of mitogen-activated protein kinases and activation of nuclear factor kappa B in normal human epidermal keratinocytes paragraph sign.

    abstract::Excessive exposure of solar ultraviolet (UV) radiation, particularly its UV-B component, to humans causes many adverse effects that include erythema, hyperplasia, hyperpigmentation, immunosuppression, photoaging and skin cancer. In recent years, there is increasing use of botanical agents in skin care products. Pomegr...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Afaq F,Malik A,Syed D,Maes D,Matsui MS,Mukhtar H

    更新日期:2005-01-01 00:00:00

  • Personal sun exposure and serum 25-hydroxy vitamin D concentrations.

    abstract::Solar ultraviolet-B radiation (UVB) is essential for epidermal vitamin D production. We aimed to quantitate the relationship between personal solar UV exposure and serum 25hydroxy vitamin D (25[OH]D) concentration. Blood was collected for 25(OH)D analysis in 207 South Australian adults aged 27-61 years. At the time of...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Nair-Shalliker V,Clements M,Fenech M,Armstrong BK

    更新日期:2013-01-01 00:00:00

  • Near-UV activation of enzymatic conversion of 5-hydroxytryptophan to serotonin.

    abstract::Near-UV (337 nm) photoactivation of the 5-hydroxytryptophan decarboxylation reaction producing serotonin has been observed. The photoactivation effect was investigated as a function of fluence rate and fluence, and pH. Photoactivation of decarboxylase activity was found to occur at nearly neutral pH values (low activi...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Fraikin GY,Strakhovskaya MG,Ivanova EV,Rubin AB

    更新日期:1989-04-01 00:00:00

  • Furocoumarin sensitization induces DNA-protein cross-links.

    abstract::The capacity of some linear and angular furocoumarins to induce DNA-protein cross-links by UVA (320-400 nm) irradiation has been evaluated in Chinese hamster ovary cells. Two linear furocoumarins, psoralen and 8-methoxypsoralen appeared to be capable of inducing DNA-protein cross-links to a noticeable extent. 4'-Methy...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Bordin F,Carlassare F,Busulini L,Baccichetti F

    更新日期:1993-07-01 00:00:00

  • Photochemical linkage of antibodies to silicon chips.

    abstract::Antibodies and antigen binding fragments thereof were photochemically immobilized on surface-modified silicon chips of 5 x 5 mm size. Silicon surface-grafted diazirines and benzophenones formed covalent bonds with the immunoreagents on light activation. Photolithographic immobilization of monoclonal antibodies in aque...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Sundarababu G,Gao H,Sigrist H

    更新日期:1995-06-01 00:00:00

  • The susceptibility of dermatophytes to photodynamic treatment with special focus on Trichophyton rubrum.

    abstract::Owing to the accessibility of skin to light, many applications of photodynamic treatment (PDT) have been developed within dermatology. The recent increase of dermatological antimicrobial PDT investigations is related to the growing problem of bacterial and fungal resistance to antibiotics. This review focuses on the s...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章,评审


    authors: Smijs TG,Pavel S

    更新日期:2011-01-01 00:00:00

  • Relation of Photochemical Internalization to Heat, pH and Ca2+ Ions.

    abstract::The inefficient endosomal escape of drugs or macromolecules is a major obstacle to achieving successful delivery to therapeutic targets. An efficient approach to circumvent this barrier is photochemical internalization (PCI), which uses light and photosensitizers for endosomal escape of the delivered macromolecules. T...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Soe TH,Nanjo T,Watanabe K,Ohtsuki T

    更新日期:2019-11-01 00:00:00

  • Energy dissipation processes of singlet-excited 1-hydroxyfluorenone and its hydrogen-bonded complex with N-methylimidazole.

    abstract::Effects of solvent, pH and hydrogen bonding with N-methylimidazole (MIm) on the photophysical properties of 1-hydroxyfluorenone (1HOF) have been studied. Fluorescence lifetime, fluorescence quantum yield and triplet yield measurements demonstrated that intersystem crossing was the dominant process in apolar media and ...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Sebok-Nagy K,Biczók L,Morimoto A,Shimada T,Inoue H

    更新日期:2004-07-01 00:00:00

  • Mutation and sister chromatid exchange induction in Chinese hamster ovary (CHO) cells by pulsed excimer laser radiation at 193 nm and 308 nm and continuous UV radiation at 254 nm.

    abstract::We compared mutagenesis and sister chromatid exchange (SCE) induction by 193 nm and 308 nm pulsed excimer laser radiation with 254 nm low intensity continuous wave UV light in Chinese hamster ovary (CHO) cells in culture. The 254 nm radiation was most mutagenic of the radiations, in accordance with expectation, and al...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Rasmussen RE,Hammer-Wilson M,Berns MW

    更新日期:1989-04-01 00:00:00

  • Photochemistry of DNA using 193 nm excimer laser radiation.

    abstract::Photoproducts in double-stranded DNA induced by 193 nm radiation have been investigated. Double-stranded, supercoiled pBR322 DNA in buffered aqueous solution was exposed to varying fluences of 193 nm radiation from an ArF excimer laser. The quantum yields for formation of cyclobutylpyrimidine dimers, frank strand brea...

    journal_title:Photochemistry and photobiology

    pub_type: 杂志文章


    authors: Kochevar IE,Buckley LA

    更新日期:1990-05-01 00:00:00