Kazimierz Strzalka

Jagiellonian University, Cracovia, Lesser Poland Voivodeship, Poland

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Publications (43)105.12 Total impact

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    ABSTRACT: Despite the well-documented information, there are insufficient reports concerning the effects of salicylate compounds on the structure and functions of cell membranes, particularly those of human erythrocytes. With the aim to better understand the molecular mechanisms of the interaction of acetylsalicylic acid (ASA) and salicylic acid (SA) with cell membranes, human erythrocyte membranes and molecular models were utilized. These consisted of bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representative of phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. The capacity of ASA and SA to perturb the multibilayer structures of DMPC and DMPE was evaluated by X-ray diffraction while DMPC unilamellar vesicles (LUV) were studied by fluorescence spectroscopy. Moreover, we took advantage of the capability of differential scanning calorimetry (DSC) to detect the changes in the thermotropic phase behavior of lipid bilayers resulting from ASA and SA interaction with PC and PE molecules. In an attempt to further elucidate their effects on cell membranes, the present work also examined their influence on the morphology of intact human erythrocytes by means of defocusing and scanning electron microscopy, while isolated unsealed human erythrocyte membranes (IUM) were studied by fluorescence spectroscopy. Results indicated that both salicylates interact with human erythrocytes and their molecular models in a concentration-dependent manner perturbing their bilayer structures.
    Archives of Biochemistry and Biophysics 09/2013; · 3.37 Impact Factor
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    ABSTRACT: Toxicity of vanadium on cells is one of the less studied effects. This prompted us to study the structural effects induced on neuroblastoma and erythrocytes by vanadium (V) sodium metavanadate. This salt was incubated with mice cholinergic neuroblastoma cells and intact human erythrocytes. To learn whether metavanadate interacts with membrane lipid bilayers it was incubated with bilayers built-up of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE). These are phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. Exposure of neuroblastoma cells to metavanadate showed significant decreases in cell viability as well as in cell number correlating with inhibition of aconitase activity. In scanning electron microscopy (SEM) and defocusing microscopy (DM) it was observed that induced on erythrocytes the formation of echinocytes. However, no effects were obtained when metavanadate was made to interact with DMPC and DMPE multibilayers and liposomes, assays performed by X-ray diffraction and differential scanning calorimetry (DSC), respectively. These results imply that the effects of metavanadate on erythrocytes are through interactions with proteins located in the membrane outer moiety, and could still involve other minor lipid components as well. Also, partly unsaturated lipids could interact differently the fully saturated chains in the model systems.
    Archives of Biochemistry and Biophysics 04/2013; · 3.37 Impact Factor
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    ABSTRACT: Research on biological influence of vanadium has gained major importance because it exerts potent toxic, mutagenic, and genotoxic effects on a wide variety of biological systems. However, hematological toxicity is one of the less studied effects. The lack of information on this issue prompted us to study the structural effects induced on the human erythrocyte membrane by vanadium (V). Sodium orthovanadate was incubated with intact erythrocytes, isolated unsealed human erythrocyte membranes (IUM) and molecular models of the erythrocyte membrane. The latter consisted of bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. This report presents evidence in order that orthovanadate interacted with red cell membranes as follows: a) in scanning electron microscopy (SEM) studies it was observed that morphological changes on human erythrocytes were induced; b) fluorescence spectroscopy experiments in isolated unsealed human erythrocyte membranes (IUM) showed that an increase in the molecular dynamics and/or water content at the shallow depth of the lipids glycerol backbone at concentrations as low as 50μM was produced; c) X-ray diffraction studies showed that orthovanadate 0.25-1mM range induced increasing structural perturbation to DMPE; d) somewhat similar effects were observed by differential scanning calorimetry (DSC) with the exception of the fact that DMPC pretransition was shown to be affected; and e) fluorescence spectroscopy experiments performed in DMPC large unilamellar vesicles (LUV) showed that at very low concentrations induced changes in DPH fluorescence anisotropy at 18°C. Additional experiments were performed in mice cholinergic neuroblastoma SN56 cells; a statistically significant decrease of cell viability was observed on orthovanadate in low or moderate concentrations.
    Biochimica et Biophysica Acta 04/2012; 1818(9):2260-70. · 4.66 Impact Factor
  • Beata Mysliwa-Kurdziel, Anna Stecka, Kazimierz Strzalka
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    ABSTRACT: In Angiosperms, the reduction of protochlorophyllide (Pchlide) to chlorophyllide (Chlide), a penultimate reaction of chlorophyll biosynthesis, is catalyzed by a photoenzyme Pchlide oxidoreductase (POR) and completely inhibited in darkness. This reaction plays also a regulatory role in plant morphogenesis. In the case of dark-grown Angiosperms, Pchlide is accumulated, mainly in the form of complexes with NADPH and POR but also as an unbound pigment. Etioplasts that develop in the place of chloroplasts in the dark contain a highly organized lipid structure termed prolamellar body (PLB), which is the main site of accumulation of the ternary Pchlide:POR:NADPH complexes. An illumination triggers the photoreduction of Pchlide molecules which are bound to the ternary complexes. This is followed by a set of biochemical reactions and structural changes leading to Chl synthesis that can be monitored with fluorescence techniques. This chapter describes the application of low-temperature fluorescence spectroscopy and fluorescence lifetime measurements for monitoring the Pchlide to Chlide conversion in isolated prolamellar bodies. These techniques enable the analysis of heterogeneity of accumulated pigments: Pchlide and Chlide that reflect the different organization of pigment-protein complexes.
    Methods in molecular biology (Clifton, N.J.) 01/2012; 875:231-9. · 1.29 Impact Factor
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    ABSTRACT: The influence of α-cis- and α-trans-polyprenols on the structure and properties of model membranes was analyzed. The interaction of Ficaprenol-12 (α-cis-Prenol-12, α-Z-Prenol-12) and Alloprenol-12 (α-trans-Prenol-12, α-E-Prenol-12) with model membranes was compared using high performance liquid chromatography (HPLC), differential scanning calorimetry (DSC) and fluorescent methods. l-α-Phosphatidylcholine from egg yolk (EYPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) as the main lipid components of unilamellar (SUVs) and multilamellar (MLVs) vesicles were used. The two-step extraction procedure (n-pentane and hexane, respectively) allowed to separately analyze the fractions of polyprenol as non-incorporated (Prenol(NonInc)) and incorporated (Prenol(Inc)) into liposomes. Consequently, distribution coefficients, P', describing the equilibrium of prenol content between phospholipid (EYPC) membrane and the aqueous phase gave different logP' for α-cis- and α-trans-Prenol-12, indicating that the configuration of the α-terminal residue significantly alters the hydrophobicity of the polyisoprenoid molecule and consequently the affinity of polyprenols for EYPC membrane. In fluorescence experiments α-trans-Pren-12 increased up to 1.7-fold the permeability of EYPC bilayer for glucose while the effect of α-cis-Pren-12 was almost negligible. Considerable changes of thermotropic behavior of DPPC membranes in the presence of both prenol isomers were observed. α-trans-Pren-12 completely abolished the pretransition while in the case of α-cis-Pren-12 it was noticeably reduced. Furthermore, for both prenol isomers, the temperature of the main phase transition (T(m)) was shifted by about 1°C to lower values and the height of the peak was significantly reduced. The DSC analysis profiles also showed a new peak at 38.7°C, which may suggest the concomitant presence of more that one phase within the membrane. Results of these experiments and the concomitant occurrence of alloprenols and ficaprenols in plant tissues suggest that cis/trans isomerization of the α-residue of polyisoprenoid molecule might comprise a putative mechanism responsible for modulation of the permeability of cellular membranes.
    Chemistry and Physics of Lipids 03/2011; 164(4):300-6. · 2.59 Impact Factor
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    KAZIMIERZ STRZALKA, RENATA SZYMANSKA, MARIO SUWALSKY
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    ABSTRACT: The content and relative composition of tocopherols, plastochromanol, plastoquinone and pigments in fifteen Antarctic species (five mosses and ten lichens) were analyzed by HPLC. Total tocopherols in mosses ranged from 90 mg/g (Warnstrofia sarmentosa) to 220 mg/g (Syntrichia magellanica), while in lichens it ranged from 0.89 mg/g in Caloplaca sp. to 45 mg/g in Placopsis contortuplicata. With the exception of Ochrolechia frigida, in all other mosses and lichens species, a-tocopherol accounted for more than 90% of total tocopherols. Plastochromanol was detected in four mosses and two lichen species; the highest level was found in Polytrichastrum alpinum (19.1 mg/g). The highest content of plastoquinone-9 (PQ-9) in mosses was found in Bryum pseudotriquetrum (42.6 mg/g), whereas in lichens it was 24.5 mg/g in Stereocaulon alpinum, and 23.17 mg/g in Umbilicaria antarctica. Pigment composition in mosses was typical for higher plants. Some lichen species lacked chlorophyll b, violaxanthin and β-carotene. Based on these results it is suggested that tocochromanols and carotenoid pigments are involved in the protection of mosses and lichens against the oxidative stress caused by the extreme Antarctic conditions.
    Journal of the Chilean Chemical Society 12/2010; 56(3):808-811. · 0.38 Impact Factor
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    ABSTRACT: Comparative study was performed to assess the content and proportions of photosynthetic pigments and the violaxanthin cycle (VXC) activity in winter-green and summer-green leaves of bugleweed (Ajuga reptans L.) plants grown in shaded (photosynthetically active radiation, PAR 150 μmol/(m2 s)) and sunny (PAR 1200 μmol/(m2 s)) habitats in the Botanic Garden of Jagiellonian University (Krakow, Poland). In overwintered and newly formed leaves of shade plants, the content of green and yellow pigments was two times higher than in leaves of sun plants. The shade plants were distinguished by accumulation of β-carotene, while lutein was predominant in leaves of sun plants. Under the action of strong light (2000 μmol/(m2s)), the level of violaxanthin deepoxidation in winter-green leaves of shade and sun plants increased five- to sixfold, whereas it changed insignificantly in summer-green leaves of shade plants. It is concluded that, in a shadetolerant species A. reptans, the photosynthetic apparatus of winter-green leaves in sun and shade plants and of summer-green leaves in sun plants is protected against excess insolation by high activity of VXC. The carotenoids of summer-green leaves in shade plants are supposed to function mainly as light-harvesting pigments. KeywordsAjuga reptans-winter-green and summer-green leaves-chlorophylls-carotenoids-violaxanthin cycle-light regime of habitats
    Russian Journal of Plant Physiology 01/2010; 57(6):755-763. · 0.62 Impact Factor
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    Beatrycze Nowicka, Wojciech Strzalka, Kazimierz Strzalka
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    ABSTRACT: Zeaxanthin epoxidase (ZE, E.C. 1.14.13.90), an enzyme belonging to the lipocalin superfamily, catalyses the conversion of zeaxanthin to antheraxanthin and violaxanthin. These reactions are part of the xanthophyll biosynthetic pathway and the xanthophyll cycle. The role of carotenoids in the dissipation of excessive light energy has been widely studied using mutants with a disabled carotenoid biosynthetic pathway. In this paper, the transgenic line MaZEP7 with partially disabled ZE activity is described and compared with wild-type plants and npq2 mutant lacking active ZE. We examined the presence and the abundance of aba1 transcripts, measured pigment composition, xanthophyll cycle functioning and chlorophyll fluorescence in all three lines. The MaZEP7 line contains additional copies of the aba1 gene introduced by agroinfiltration, but no enhanced aba1 transcript level was observed. In addition, ZE activity in MaZEP7 was impaired, resulting in an altered xanthophyll profile. In dark-adapted plants, violaxanthin and neoxanthin levels were lower than in wild-type plants, whereas antheraxanthin and zeaxanthin levels were considerably higher. The presence of lutein epoxide was also observed. Violaxanthin levels changed only minimally during light exposition, whereas antheraxanthin was converted to zeaxanthin and there was no epoxidation during the course of the experiment indicating disturbed xanthophyll cycle functioning. The amounts of carotenoids and chlorophylls on a dry weight basis and chl a/chl b ratio were similar in all lines. The presence of epoxidated pigments in MaZEP7 plants indicates that epoxidation occurs, but it is likely very slow. Chlorophyll fluorescence measurements showed that the dependence of electron transport rates on light intensity for the MaZEP7 line resembled the npq2 mutant. Kinetic measurements showed that the MaZEP7 line exhibited very rapid induction and a high steady-state value of non-photochemical quenching.
    Journal of plant physiology 04/2009; 166(10):1045-56. · 2.50 Impact Factor
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    ABSTRACT: Phosphatidylglycerol (PG) depletion suppressed the oxygenevolving activity of Synechocystis PCC6803 pgsA mutant cells. Shortage of PG led to decreased photosynthetic activity, which, similar to the effect of high light exposure, is likely to generate the production of reactive oxygen species (ROS) or free radicals. Protection of the PG-depleted cells against light-induced damage increased the echinenone and myxoxanthophyll content of the cells. The increased carotenoid content was localized in a soluble fraction of the cells as well as in isolated thylakoid and cytoplasmic membranes. The soluble carotenoid fraction contained carotene derivatives, which may bind to proteins. These carotene–protein complexes are similar to orange carotenoid protein that is involved in yielding protection against free radicals and ROS. An increase in the content of myxoxanthophyll and echinenone upon PG depletion suggests that PG depletion regulates the biosynthetic pathway of specifi c carotenoids
    Plant and Cell Physiology 02/2009; 50:1-9.. · 4.13 Impact Factor
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    Peter Jahns, Dariusz Latowski, Kazimierz Strzalka
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    ABSTRACT: The violaxanthin cycle describes the reversible conversion of violaxanthin to zeaxanthin via the intermediate antheraxanthin. This light-dependent xanthophyll conversion is essential for the adaptation of plants and algae to different light conditions and allows a reversible switch of photosynthetic light-harvesting complexes between a light-harvesting state under low light and a dissipative state under high light. The photoprotective functions of zeaxanthin have been intensively studied during the last decade, but much less attention has been directed to the mechanism and regulation of xanthophyll conversion. In this review, an overview is given on recent progress in the understanding of the role of (i) xanthophyll binding by antenna proteins and of (ii) the lipid properties of the thylakoid membrane in the regulation of xanthophyll conversion. The consequences of these findings for the mechanism and regulation of xanthophyll conversion in the thylakoid membrane will be discussed.
    Biochimica et Biophysica Acta 11/2008; 1787(1):3-14. · 4.66 Impact Factor
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    ABSTRACT: The effect of high temperature treatment (40 degrees C, 3 h, illumination at 100 micromol m(-2) s(-1)) on the photosynthetic electron flow in barley seedlings of different age was investigated. Thermoinduced inhibition of the liner electron flow due to partial impairment of the water oxidizing complex (WOC) and the increase in the extent of Q(A)(-) reoxidation by Tyr(z)(ox) in thylakoids isolated from 4-day-old leaves was shown by measurements of oxygen evolution using benzoquinone or potassium ferricyanide as electron acceptors, as well as by following Q(A)(-) reoxidation kinetics in the absence and presence of exogenous electron acceptors, DCBQ and DMBQ. Using HPLC analysis, an increase in the oxidation of the photoactive plastoquinone pool in young leaves under heating was shown. In older, 11-day-old leaves, heat treatment limited both photosynthetic electron flow and oxygen evolution. The same effects of heat shock on oxygen evolution caused an inhibition of electron flow on the donor side of PSII only. However, a rise in the proportion of PSII with Q(A)(-) reoxidized through recombination with the S(2)/S(3) state of the WOC was observed. The addition of exogenous electron acceptors (DCBQ and DMBQ) and a donor (DPC) showed that the thermoinduced decrease in the electron transport rate was caused by an impediment of electron flow from Q(A)(-) to acceptor pool. The decrease in size of the photoactive PQ-pool and a change in the proportions of oxidized and reduced PQ in older leaves under heat treatment were shown. It was suggested that a thermoinduced change of the redox state of the PQ-pool and a redistribution of plastoquinone molecules between photoactive and non-photoactive pools are the mechanisms which reflect and regulate the response of the photosynthetic apparatus under heat stress conditions.
    Biochimica et Biophysica Acta 09/2008; 1777(11):1393-9. · 4.66 Impact Factor
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    ABSTRACT: Methylation of inorganic arsenic has been regarded as a detoxification mechanism because its metabolites monomethylarsonic acid (MMA(v)) and dimethylarsinic acid (DMA(v)) are supposed to be less toxic than inorganic arsenite and arsenate. In recent years, however, this interpretation has been questioned. Additionally, there are insufficient reports concerning the effects of arsenic compounds on cell membrane structure and functions. With the aim to better understand the molecular mechanisms of the interaction of MMA(v) and arsenate with cell membranes, we have utilized molecular models consisting in bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representative of phospholipid classes located in the outer and inner monolayers of many cell membranes including that of the human erythrocyte. The capacity of MMA(v) and arsenate to perturb the bilayer structures of DMPC and DMPE was evaluated by X-ray diffraction; the modifications of their thermotropic behavior were followed by differential scanning calorimetry (DSC), while DMPC large unilamellar vesicles (LUV) were studied by fluorescence spectroscopy. It was found that MMA(v) and arsenate did not structurally perturb DMPC bilayers; however, DMPE bilayers did suffer structural perturbations by MMA(v). DSC measurements also revealed that DMPE's thermotropic properties were significantly affected by arsenicals, where MMA(v) was more effective than arsenate, whilst only slight modifications were observed in the case of DMPC-MMA(v) system.
    Biophysical Chemistry 02/2008; 132(1):1-8. · 2.28 Impact Factor
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    ABSTRACT: We have examined the mode of interaction between cadmium (Cd) and zinc (Zn), toxic and micronutrient elements, on the photosynthetic apparatus, with respect to energy transfer in leaves of the free-floating macrophyte Ceratophyllum demersum L. Low temperature fluorescence spectroscopy enabled in situ detection of changes in energy transfer from pigments energetically coupled to PS I and PS II, induced by Cd and Zn in C. demersum. The two-point normalization algorithm permitted a direct comparison of the shape of excitation spectra in the wavelength range including absorption maxima of main photosynthetic pigments (from 438 to 555 nm). The results indicate that Cd and Zn in concentrations up to 1000 μM can induce remarkable changes in energy transfer from carotenoids to reaction centers of PS II and antenna complexes LHC II in C. demersum leaves. Cd at 1000 μM, after 48 hr incubation, induced the most pronounced increase of fluorescence from PS II/LHC II, attributable to excitation of the carotenoid pool (482 and 486 nm bands). The presence of Zn (100 μM) together with Cd (1000 μM) suppressed the observed increase of carotenoid contribution to energy transfer to photosynthetic reaction centers in PS II/LHC II. The changes in the contribution of carotenoids to energy transfer, as observed by low-temperature fluorescence spectroscopy show no direct correlation with relative changes in concentrations of these pigments in untreated versus metal-treated C. demersum, as measured by HPLC. In conclusion, the presence of Zn in the environment may prevent effects on photosynthetic energy transfer, induced by high concentrations of Cd in PS II/LHC II of aquatic plants.
    Plant Stress. 01/2008; 2(2):121-126.
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    ABSTRACT: We investigated the influence of cuprous ions, Cu2+, on energy and electron transport in photosystem II (PSII) using fluorescence methods. It has been suggested that the primary targets in PSII for copper are tyrosine Z, cytochrome b559, chlorophyll Z and the quinone-iron complex. Here, we present studies on Cu2+ action on thylakoid membranes and thylakoids enriched in PSII isolated from a wild-type tobacco and from a mutant with a point mutation on the β-chain of cytochrome b559. We observed that copper ions modify in various ways the efficiency of the energy and electron transfer in PSII in both the wild type and the mutant. The action of Cu2+ is additionally influenced by the presence of sulfate anions. We can distinguish at least three different modes of copper acting on the electron and energy transfer within PSII.
    12/2007: pages 657-660;
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    ABSTRACT: We investigated the inhibitory action of cadmium ions on the energy and electron transfer within PSII using fluorescence spectroscopy. We have examined thylakoid membranes isolated from a wild type (WT) and a mutant (M) of tobacco with a point mutation in the β-chain of cytochrome b559. Variable fluorescence measurements were made of PSII samples treated with various concentrations of cadmium salts. From these experiments we were able to determine the impact of the cadmium cations on the efficiency of photochemical processes within PSII and the activity of its acceptor side. We observed that cadmium ions act differently on the WT and M in the presence of chloride anions. Sulfate ions enhanced the inhibitory effect of Cd2+ but at low concentrations, CdSO4 diminished some characteristic transitions monitored for CdCl2. At the lowest applied concentrations, the salts had no influence on the Kautsky effect in the mutant, whereas a strong effect is observed in the WT. This phenomenon is related to the point mutation of cytochrome b559 which is supposed to modify the QB binding site on the acceptor side of PSII (Burda et al., these Proceedings). At higher applied concentrations of Cd salts, one has to consider additional Cd2+ interactions with chlorophylls from the light harvesting antenna.
    12/2007: pages 311-314;
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    ABSTRACT: We Present Studies On Energy And Electron Transfer Within Photosystem Ii (Psii) In Thylakoid Membranes And Bby Psii Isolated From A Wild Type Of Tobacco And A Mutant. We Monitored Energy Transfer Into The Reaction Center And The Kinetics Of Electron Transport At The Psii Acceptor Side Using Steady State And Double Modulated Fluorescence Spectroscopy. Using Measurements Of Oxygen Evolution Under Short Saturating Flashesmade With A Three-Electrode System, We Determined The Redox Properties Of 4Mnca–Complex And The Efficiency Of Transfer Between Its S-States On The Psii Donor Side. We Conclude That A Phe-Ser Point Mutation In The β-Chain Of Cytochrome B559 Causes A Structural Modification Of The QB Binding Site At The Acceptor Site Of Psii, Changing Its Ability To Bind Plastoquinone Molecules.
    12/2007: pages 563-568;
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    ABSTRACT: There are scanty reports concerning the effects of arsenic compounds on the structure and functions of cell membranes. With the aim to better understand the molecular mechanisms of the interaction of arsenite with cell membranes we have utilized bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representative of phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. The capacity of arsenite to perturb the bilayer structures was determined by X-ray diffraction and fluorescence spectroscopy, whilst the modification of their thermotropic behaviour was followed by differential scanning calorimetry (DSC). The experiments carried out by X-ray diffraction and calorimetry clearly indicated that NaAsO(2) interacted with DMPE and modified its thermotropic behaviour. No such information has been so far reported in the literature.
    Biophysical Chemistry 05/2007; 127(1-2):28-35. · 2.28 Impact Factor
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    ABSTRACT: In the present study, the solubility and enzymatic de-epoxidation of diadinoxanthin (Ddx) was investigated in three different artificial membrane systems: (1) Unilamellar liposomes composed of different concentrations of the bilayer forming lipid phosphatidylcholine (PC) and the inverted hexagonal phase (H(II) phase) forming lipid monogalactosyldiacylglycerol (MGDG), (2) liposomes composed of PC and the H(II) phase forming lipid phosphatidylethanolamine (PE), and (3) an artificial membrane system composed of digalactosyldiacylglycerol (DGDG) and MGDG, which resembles the lipid composition of the natural thylakoid membrane. Our results show that Ddx de-epoxidation strongly depends on the concentration of the inverted hexagonal phase forming lipids MGDG or PE in the liposomes composed of PC or DGDG, thus indicating that the presence of inverted hexagonal structures is essential for Ddx de-epoxidation. The difference observed for the solubilization of Ddx in H(II) phase forming lipids compared with bilayer forming lipids indicates that Ddx is not equally distributed in the liposomes composed of different concentrations of bilayer versus non-bilayer lipids. In artificial membranes with a high percentage of bilayer lipids, a large part of Ddx is located in the membrane bilayer. In membranes composed of equal proportions of bilayer and H(II) phase forming lipids, the majority of the Ddx molecules is located in the inverted hexagonal structures. The significance of the pigment distribution and the three-dimensional structure of the H(II) phase for the de-epoxidation reaction is discussed, and a possible scenario for the lipid dependence of Ddx (and violaxanthin) de-epoxidation in the native thylakoid membrane is proposed.
    Biochimica et Biophysica Acta 02/2007; 1768(1):67-75. · 4.66 Impact Factor
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    ABSTRACT: This study is part of a project aimed at examining the influence of arsenic on biological membranes. By the use of differential scanning calorimetry (DSC) we have followed the thermotropic behavior of multilamellar vesicles prepared from dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE) upon incorporation of sodium arsenite (AsI), disodium arsenate (AsII), cacodylic acid (AsIII) and disodium methyl arsenate (AsIV).The effectiveness of perturbations exerted by various arsenic compounds on thermotropic phase transition was further analysed in terms of thermodynamic parameters: transition temperature, enthalpy and molar heat capacity, determined for lipid/As systems on the basis of heating and cooling scans. It is found that while it only has a slight influence on the thermotropic properties of DMPC, arsenic is able to significantly modify DMPE model membranes.
    Thermochimica Acta. 01/2007;
  • Comparative Biochemistry and Physiology A-molecular & Integrative Physiology - COMP BIOCHEM PHYSIOL PT A. 01/2007; 146(4).

Publication Stats

424 Citations
105.12 Total Impact Points

Institutions

  • 1992–2013
    • Jagiellonian University
      • • Department of Plant Physiology and Biochemistry
      • • Faculty of Biochemistry, Biophysics and Biotechnology
      Cracovia, Lesser Poland Voivodeship, Poland
    • University of Liège
      • Laboratory of Tissue Biology
      Liège, WAL, Belgium
  • 2011
    • Polish Academy of Sciences
      • Instytut Chemii Fizycznej
      Warsaw, Masovian Voivodeship, Poland
  • 2008
    • Heinrich-Heine-Universität Düsseldorf
      • Institute of Plant Biochemistry
      Düsseldorf, North Rhine-Westphalia, Germany
    • National Academy of Sciences of Belarus
      • Institute of Biophysics and Cell Engineering
      Minsk, Minskaya Voblasts', Belarus
  • 2007–2008
    • University of Concepción
      Ciudad de Concepcion, Biobío, Chile
  • 2005–2007
    • University of Leipzig
      • Institut für Biologie
      Leipzig, Saxony, Germany
  • 1998–2000
    • Roche Institute of Molecular Biology
      Nutley, New Jersey, United States