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Lopes-de-Campos D, Pereira-Leite C, Fontaine P, Coutinho A, Prieto M, Sarmento B, Jakobtorweihen S, Nunes C, Reis S. Interface-Mediated Mechanism of Action-The Root of the Cytoprotective Effect of Immediate-Release Omeprazole. J Med Chem 2021; 64:5171-5184. [PMID: 33847502 DOI: 10.1021/acs.jmedchem.1c00251] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Omeprazole is usually administered under an enteric coating. However, there is a Food and Drug Administration-approved strategy that enables its release in the stomach. When locally absorbed, omeprazole shows a higher efficacy and a cytoprotective effect, whose mechanism was still unknown. Therefore, we aimed to assess the effect of the absorption route on the gastric mucosa. 2D and 3D models of dipalmitoylphosphatidylcholine (DPPC) at different pH values (5.0 and 7.4) were used to mimic different absorption conditions. Several experimental techniques, namely, fluorescence studies, X-ray scattering methodologies, and Langmuir monolayers coupled with microscopy, X-ray diffraction, and infrared spectroscopy techniques, were combined with molecular dynamics simulations. The results showed that electrostatic and hydrophobic interactions between omeprazole and DPPC rearranged the conformational state of DPPC. Omeprazole intercalates among DPPC molecules, promoting domain formation with untilted phospholipids. Hence, the local release of omeprazole enables its action as a phospholipid-like drug, which can reinforce and protect the gastric mucosa.
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Affiliation(s)
- Daniela Lopes-de-Campos
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313 Porto, Portugal
| | - Catarina Pereira-Leite
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313 Porto, Portugal
| | - Philippe Fontaine
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, BP48, 91192 Gif-sur-Yvette, France
| | - Ana Coutinho
- IBB-Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.,Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Manuel Prieto
- IBB-Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Bruno Sarmento
- INEB-Instituto de Engenharia Biomédica, Universidade do Porto, 4200-135 Porto, Portugal.,i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.,IINFACTS, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Instituto Universitário de Ciências da Saúde, 4585-116 Gandra, Portugal
| | - Sven Jakobtorweihen
- Institute of Thermal Separation Processes, Hamburg University of Technology, 21073 Hamburg, Germany
| | - Cláudia Nunes
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313 Porto, Portugal
| | - Salette Reis
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, 4050-313 Porto, Portugal
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Lopes-de-Campos D, Nunes C, Sarmento B, Jakobtorweihen S, Reis S. Metronidazole within phosphatidylcholine lipid membranes: New insights to improve the design of imidazole derivatives. Eur J Pharm Biopharm 2018; 129:204-14. [PMID: 29859282 DOI: 10.1016/j.ejpb.2018.05.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 05/17/2018] [Accepted: 05/29/2018] [Indexed: 12/17/2022]
Abstract
Metronidazole is a imidazole derivative with antibacterial and antiprotozoal activity. Despite its therapeutic efficacy, several studies have been developing new imidazole derivatives with lower toxicity. Considering that drug-membrane interactions are key factors for drugs pharmacokinetic and pharmacodynamic properties, the aim of this work is to provide new insights into the structure-toxicity relationship of metronidazole within phosphatidylcholine membranes. For that purpose, lipid membrane models (liposomes and monolayers) composed of dipalmitoylphosphatidylcholine were used. Experimental techniques (determination of partition coefficients and Langmuir isotherm measurements) were combined with molecular dynamics simulations. Different pHs and lipid phases were evaluated to enable a better extrapolation for in vivo conditions. The partition of metronidazole depends on the pH and on the biphasic system (octanol/water or DPPC/water system). At pH 1.2, metronidazole is hydrophilic. At pH 7.4, metronidazole disturbs the order and the packing of phospholipids. For this toxic effect, the hydroxyl group of the side chain of metronidazole is crucial by interacting with the water embedded in the membrane and with the phosphate group and the apolar chains of phospholipids.
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Wang D, de Jong DH, Rühling A, Lesch V, Shimizu K, Wulff S, Heuer A, Glorius F, Galla HJ. Imidazolium-Based Lipid Analogues and Their Interaction with Phosphatidylcholine Membranes. Langmuir 2016; 32:12579-12592. [PMID: 27934518 DOI: 10.1021/acs.langmuir.6b02496] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
4,5-Dialkylated imidazolium lipid salts are a new class of lipid analogues showing distinct biological activities. The potential effects of the imidazolium lipids on artificial lipid membranes and the corresponding membrane interactions was analyzed. Therefore, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) was employed to create an established lipid monolayer model and a bilayer membrane. Mixed monolayers of DPPC and 4,5-dialkylimidazolium lipids differing by their alkyl chain length (C7, C11, and C15) were characterized by surface pressure-area (π-A) isotherms using a Wilhelmy film balance in combination with epifluorescence microscopy. Monolayer hysteresis for binary mixtures was examined by recording triplicate consecutive compression-expansion cycles. The lipid miscibility and membrane stability of DPPC/imidazolium lipids were subsequently evaluated by the excess mean molecular area (ΔAex) and the excess Gibbs free energy (ΔGex) of mixing. Furthermore, the thermotropic behavior of mixed liposomes of DPPC/imidazolium lipids was investigated by differential scanning calorimetry (DSC). The C15-imidazolium lipid (C15-IMe·HI) forms a thermodynamically favored and kinetically reversible Langmuir monolayer with DPPC and exhibits a rigidification effect on both DPPC monolayer and bilayer structures at low molar fractions (X ≤ 0.3). However, the incorporation of the C11-imidazolium lipid (C11-IMe·HI) causes the formation of an unstable and irreversible Langmuir-Gibbs monolayer with DPPC and disordered DPPC liposomes. The C7-imidazolium lipid (C7-IMe·HI) displays negligible membrane activity. To better understand these results on a molecular level, all-atom molecular dynamics (MD) simulations were performed. The simulations yield two opposing molecular mechanisms governing the different behavior of the three imidazolium lipids: a lateral ordering effect and a free volume/stretching effect. Overall, our study provides the first evidence that the membrane interaction of the C15 and C11 derivatives modulates the structural organization of lipid membranes. On the contrary, for the C7 derivative its membrane activity is too low to contribute to its earlier reported potent cytotoxicity.
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Affiliation(s)
- Da Wang
- Institut für Biochemie, ‡Institut für Physikalische Chemie, and §Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster , Wilhelm-Klemm-Straße 2, D-48149 Münster, Germany
| | - Djurre H de Jong
- Institut für Biochemie, ‡Institut für Physikalische Chemie, and §Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster , Wilhelm-Klemm-Straße 2, D-48149 Münster, Germany
| | - Andreas Rühling
- Institut für Biochemie, ‡Institut für Physikalische Chemie, and §Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster , Wilhelm-Klemm-Straße 2, D-48149 Münster, Germany
| | - Volker Lesch
- Institut für Biochemie, ‡Institut für Physikalische Chemie, and §Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster , Wilhelm-Klemm-Straße 2, D-48149 Münster, Germany
| | - Karina Shimizu
- Institut für Biochemie, ‡Institut für Physikalische Chemie, and §Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster , Wilhelm-Klemm-Straße 2, D-48149 Münster, Germany
| | - Stephanie Wulff
- Institut für Biochemie, ‡Institut für Physikalische Chemie, and §Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster , Wilhelm-Klemm-Straße 2, D-48149 Münster, Germany
| | - Andreas Heuer
- Institut für Biochemie, ‡Institut für Physikalische Chemie, and §Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster , Wilhelm-Klemm-Straße 2, D-48149 Münster, Germany
| | - Frank Glorius
- Institut für Biochemie, ‡Institut für Physikalische Chemie, and §Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster , Wilhelm-Klemm-Straße 2, D-48149 Münster, Germany
| | - Hans-Joachim Galla
- Institut für Biochemie, ‡Institut für Physikalische Chemie, and §Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster , Wilhelm-Klemm-Straße 2, D-48149 Münster, Germany
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Flasiński M, Wydro P, Broniatowski M. Lyso-phosphatidylcholines in Langmuir monolayers – Influence of chain length on physicochemical characteristics of single-chained lipids. J Colloid Interface Sci 2014; 418:20-30. [DOI: 10.1016/j.jcis.2013.12.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2013] [Revised: 11/29/2013] [Accepted: 12/01/2013] [Indexed: 01/23/2023]
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Flasiński M, Broniatowski M, Wydro P, Dynarowicz-Łątka P. Comparative Characteristics of Membrane-Active Single-Chained Ether Phospholipids: PAF and Lyso-PAF in Langmuir Monolayers. J Phys Chem B 2012; 116:3155-63. [DOI: 10.1021/jp2121092] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Michał Flasiński
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
| | - Marcin Broniatowski
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
| | - Paweł Wydro
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
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Naumowicz M, Petelska AD, Figaszewski ZA. Impedance analysis of complex formation equilibria in phosphatidylcholine bilayers containing decanoic acid or decylamine. Cell Biochem Biophys 2011; 61:145-55. [PMID: 21340532 DOI: 10.1007/s12013-011-9171-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Bilayer lipid membranes composed of phosphatidylcholine and decanoic acid or phosphatidylcholine and decylamine were investigated using electrochemical impedance spectroscopy. Interaction between membrane components causes significant deviations from the additivity rule. Area, capacitance, and stability constant values for the complexes were calculated based on the model assuming 1:1 stoichiometry, and the model was validated by comparison of these values to experimental results. We established that phosphatidylcholine and decylamine form highly stable 1:1 complexes. In the case of decanoic acid-modified phosphatidylcholine membranes, complexes with stoichiometries other than 1:1 should be taken into consideration.
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Nunes C, Brezesinski G, Lopes D, Lima JL, Reis S, Lúcio M. Lipid–Drug Interaction: Biophysical Effects of Tolmetin on Membrane Mimetic Systems of Different Dimensionality. J Phys Chem B 2011; 115:12615-23. [DOI: 10.1021/jp206013z] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Cláudia Nunes
- REQUIMTE, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, 164, Rua Aníbal Cunha, Porto, Portugal
| | - Gerald Brezesinski
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, Am Mühlenberg 1, D-14476 Potsdam, Germany
| | - Daniela Lopes
- REQUIMTE, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, 164, Rua Aníbal Cunha, Porto, Portugal
| | - José L.F.C. Lima
- REQUIMTE, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, 164, Rua Aníbal Cunha, Porto, Portugal
| | - Salette Reis
- REQUIMTE, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, 164, Rua Aníbal Cunha, Porto, Portugal
| | - Marlene Lúcio
- REQUIMTE, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, 164, Rua Aníbal Cunha, Porto, Portugal
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Flasiński M, Broniatowski M, Majewski J, Dynarowicz-Łątka P. X-ray grazing incidence diffraction and Langmuir monolayer studies of the interaction of β-cyclodextrin with model lipid membranes. J Colloid Interface Sci 2010; 348:511-21. [DOI: 10.1016/j.jcis.2010.04.086] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 04/28/2010] [Accepted: 04/29/2010] [Indexed: 11/16/2022]
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Wiacek AE, Holysz L, Chibowski E. Effect of temperature on n-tetradecane emulsion in the presence of phospholipid DPPC and enzyme lipase or phospholipase A2. Langmuir 2008; 24:7413-7420. [PMID: 18564865 DOI: 10.1021/la800794x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Zeta potentials and effective diameters of n-tetradecane emulsions in 1 M ethanol were investigated in the presence of 1,2-dipalmitoyl- sn-glycero-3-phosphocholine (DPPC) (1 mg/100 mL), Candida cylindracea lipase (CCL), and phospholipase PLA2 (1 mg/100 mL) at 20, 37, and 45 degrees C. The enzyme was added at the beginning of mechanical emulsion homogenization or 1 min before the end of stirring for 10 min at 10,000 rpm. It was found that DPPC decreases the negative zeta potentials at all three temperatures. The decrease was largest at 20 degrees C and smallest at 45 degrees C. The influence of the enzymes on the zeta potentials depended on the enzyme kind, time of its injection, and temperature. More negative values of the zeta potentials relative to n-C14H30/DPPC droplets were obtained if the lipase was present. Generally, the effective diameters correlate with the zeta potentials, i.e., lower zeta potential corresponds with bigger effective diameter. Possible reasons for the observed changes of the measured parameters are discussed.
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Affiliation(s)
- Agnieszka Ewa Wiacek
- Department of Physical Chemistry, Interfacial Phenomena, Faculty of Chemistry, Maria Curie Sklodowska University, 20-031 Lublin, Poland
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Wagner K, Desbat B, Brezesinski G. Liquid–liquid immiscibility in model membranes activates secretory phospholipase A2. Biochimica et Biophysica Acta (BBA) - Biomembranes 2008; 1778:166-74. [DOI: 10.1016/j.bbamem.2007.09.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2007] [Revised: 09/17/2007] [Accepted: 09/19/2007] [Indexed: 01/16/2023]
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Hac-Wydro K, Wydro P. The influence of fatty acids on model cholesterol/phospholipid membranes. Chem Phys Lipids 2007; 150:66-81. [PMID: 17651712 DOI: 10.1016/j.chemphyslip.2007.06.213] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2006] [Revised: 05/24/2007] [Accepted: 06/17/2007] [Indexed: 10/23/2022]
Abstract
The aim of this work was to verify the influence of the saturated (SFA) (stearic acid) and the unsaturated (UFA) (oleic and alpha-linolenic) fatty acids on model cholesterol/phospholipid membranes. The experiments were based on the Langmuir monolayer technique. Cholesterol and phospholipid were mixed in the molar ratio that corresponds to the proportion of these lipids in the majority of natural human membranes. Into the binary cholesterol/phospholipid monolayers, various amounts of fatty acids were incorporated. Our investigations were based on the analysis of the interactions between molecules in ternary (cholesterol/phospholipids/fatty acid) mixtures, however, also binary (cholesterol/fatty acid and phospholipids/fatty acid) mixed system were examined. It was concluded that the influence of the fatty acids on model cholesterol/phospholipid membrane is closely connected with the shape of the fatty acid molecule, resulting from the saturation degree of the hydrocarbon chain. It was found that the saturated fatty acid makes the model membrane more rigid, while the presence of unsaturated fatty acid increases its fluidity. The increasing amount of stearic acid gradually destabilizes model membrane, however, this effect is the weakest at low content of SFA in the mixed monolayer. Unsaturated fatty acids in a small proportion make the membrane thermodynamically more stable, while higher content of UFA decreases membrane stability. This explains low proportion of the free fatty acids to other lipids in natural membrane.
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Affiliation(s)
- Katarzyna Hac-Wydro
- Department of General Chemistry, Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
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Abstract
Lysopalmitoylphosphatidylcholine (LPC) black films have been studied by confocal Raman spectroscopy and their spectra analyzed and compared to their counterparts obtained from LPC in the solid state and aqueous solution. It appears that LPC is able to form stable and highly ordered black films, despite the presence of only one hydrophobic chain in this molecule. A complementary infrared study of LPC Gibbs monolayers suggests that the whole LPC polar head is perpendicular to the air/water interface. Such an orientation could explain the high order and the close packing observed in black films.
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Affiliation(s)
- Florent Sandras
- Centre de Physique Moléculaire Optique et Hertzienne, UMR 5798 du CNRS, Université Bordeaux 1, 351 cours de la libération, 33405 Talence Cedex, France
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Hac-Wydro K, Dynarowicz-Łatka P, Grzybowska J, Borowski E. Interactions of amphotericin B derivative of low toxicity with biological membrane components—the Langmuir monolayer approach. Biophys Chem 2005; 116:77-88. [PMID: 15911084 DOI: 10.1016/j.bpc.2005.03.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2004] [Revised: 03/02/2005] [Accepted: 03/07/2005] [Indexed: 10/25/2022]
Abstract
Amphotericin B (AmB)--a polyene macrolide antibiotic--exhibits strong antifungal activity, however, is known to be very toxic to mammalian cells. In order to decrease AmB toxicity, a number of its derivatives have been synthesized. Basing on in vitro and in vivo research, it was evidenced that one of AmB derivatives, namely N-methyl-N-D-fructopyranosylamphotericin B methyl ester (in short MF-AME) retained most of the antifungal activity of the parent antibiotic, however, exhibited dramatically lower animal toxicity. Therefore, MF-AME seems to be a very promising modification product of AmB. However, further development of this derivative as potential new antifungal drug requires the elucidation of its molecular mechanism of reduced toxicity, which was the aim of the present investigations. Our studies were based on examining the binding energies by determining the strength of interaction between MF-AME and membrane sterols (ergosterol-fungi sterol, and cholesterol-mammalian sterol) and DPPC (model membrane phospholipid) using the Langmuir monolayer technique, which serves as a model of cellular membrane. Our results revealed that at low concentration the affinity of MF-AME to ergosterol is considerably stronger as compared to cholesterol, which correlates with the improved selective toxicity of this drug. It is of importance that the presence of phospholipids is essential since--due to very strong interactions between MF-AME and DPPC--the antibiotic used in higher concentration is "immobilized" by DPPC molecules, which reduces the concentration of free antibiotic, thus enabling it to selectively interact with both sterols.
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Affiliation(s)
- K Hac-Wydro
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
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Morisaku T, Yui H, Iwazumi M, Ikezoe Y, Fujinami M, Sawada T. Real-Time Observation for the Enzymatic Reaction of Phospholipid Membrane: Application of the Time-Resolved Quasi-Elastic Laser Scattering Method. Anal Chem 2004; 76:2314-20. [PMID: 15080743 DOI: 10.1021/ac030320b] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An analytical technique to measure reactions in biological membranes was developed and applied to monitoring the hydrolysis reaction of phospholipids (dipalmitoylphosphatidylcholine, DPPC) by phospholipase A(2). The technique uses the time-resolved quasi-elastic laser scattering (TR-QELS) method to measure an oil/phospholipid monolayer/water membrane system by monitoring the change of interfacial tension under a noncontact condition and in real time. When the TR-QELS method is used with the newly developed oil/phospholipid monolayer/water membrane system, measurement of the hydrolysis reaction of phospholipids with long alkyl chains (C >or=16), which are the major components in biological membranes, becomes possible. The reaction progress is monitored by the increase of interfacial tension at the oil/water interface caused by the decrease of surface-active DPPC molecules due to the reaction. The characteristic phases, namely, lag, burst, and equilibrium, are observed. The relationship between the duration of the lag phase (the rate-limiting step of the reaction) and the concentration of calcium ion (an essential cofactor of the reaction) is also investigated. Increase of calcium ion concentration in the subphase is found to shorten the duration of the lag phase. In addition, the real-time measurement simplifies the estimation process for the reaction activation energy.
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Affiliation(s)
- Toshinori Morisaku
- Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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Yui H, Ikezoe Y, Sawada T. Dynamic Behaviors of Molecular Assemblies at Liquid/Liquid Interfaces Studied by Time-Resolved Quasi-Elastic Laser Scattering Spectroscopy. ANAL SCI 2004; 20:1501-7. [PMID: 15566140 DOI: 10.2116/analsci.20.1501] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The dynamic behaviors of molecular assemblies at two immiscible liquid interfaces are intriguing topics in many fields of science and technology. However, it is generally difficult to investigate the dynamic behaviors of such molecular assemblies because of the buried nature of liquid/liquid interfaces. In the present paper, our recent investigations on dynamic behaviors of various molecular self-assemblies at liquid/liquid interfaces are reviewed. We monitored dynamic behaviors of the molecular assemblies by time-resolved quasi-elastic laser scattering (TR-QELS) and fluorescent spectroscopy. The former method allows us to monitor the change in interfacial tension with millisecond time-resolution. As molecular assemblies, bis(2-ethylhexyl)sulfosuccinate (AOT) microemulsion, phospholipid biomembrane models, and liposome-DNA complexes have all been studied, since they are relevant in material sciences and biological technologies. At liquid/liquid interfaces, these molecular assemblies showed characteristic behaviors. We review the finding of rebound response of the interfacial tension at the liquid/liquid interface induced by the adsorption of the AOT microemulsion. We monitored the hydrolysis reaction of phospholipid biomembrane models formed at oil/water interfaces, observing the different types of behavior of liposome-DNA complexes at biomembrane models with different kinds of phospholipids.
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Affiliation(s)
- Hiroharu Yui
- CREST Japan Science and Technology Agency, Nanoarchitectonics Research Center, National Institute of Advanced Industrial Science and Technology, Tsukuba Central 4, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8562, Japan.
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Marie-hélène R, Brezesinski G, Möhwald H. Enzymatic Reactions at Interfaces. Organized Monolayers and Assemblies: Structure, Processes and Function. Elsevier; 2002. pp. 207-46. [DOI: 10.1016/s1383-7303(02)80006-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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