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Casein interaction with lipid membranes: Are the phase state or charge density of the phospholipids affecting protein adsorption? BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:2588-2598. [DOI: 10.1016/j.bbamem.2018.09.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 09/11/2018] [Accepted: 09/26/2018] [Indexed: 01/03/2023]
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2
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The interfacial properties of various milk fat globule membrane components using Langmuir isotherms. FOOD BIOSCI 2017. [DOI: 10.1016/j.fbio.2017.08.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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3
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Removal of Cr(VI) and Hg(II) ions from wastewater by novel β-CD/MGO-SO3H composite. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2016.10.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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4
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Goswami A, Hassan P, Bhagwat SS. Static and dynamic surface tension behaviour of a triblock copolymer and a non ionic surfactant mixture. Colloids Surf A Physicochem Eng Asp 2015. [DOI: 10.1016/j.colsurfa.2015.07.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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5
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Dilli G, Unsal H, Uslu B, Aydogan N. Restoration of the interfacial properties of lung surfactant with a newly designed hydrocarbon/fluorocarbon lipid. Colloids Surf B Biointerfaces 2014; 122:566-575. [DOI: 10.1016/j.colsurfb.2014.07.034] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 07/16/2014] [Accepted: 07/21/2014] [Indexed: 11/30/2022]
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6
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Penetration of milk-derived antimicrobial peptides into phospholipid monolayers as model biomembranes. Biochem Res Int 2013; 2013:914540. [PMID: 24455264 PMCID: PMC3877611 DOI: 10.1155/2013/914540] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 08/27/2013] [Accepted: 08/27/2013] [Indexed: 12/18/2022] Open
Abstract
Three antimicrobial peptides derived from bovine milk proteins were examined with regard to penetration into insoluble monolayers formed with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or 1,2-dipalmitoyl-sn-glycero-3-phospho-rac-(1-glycerol) sodium salt (DPPG). Effects on surface pressure (Π) and electric surface potential (ΔV) were measured, Π with a platinum Wilhelmy plate and ΔV with a vibrating plate. The penetration measurements were performed under stationary diffusion conditions and upon the compression of the monolayers. The two type measurements showed greatly different effects of the peptide-lipid interactions. Results of the stationary penetration show that the peptide interactions with DPPC monolayer are weak, repulsive, and nonspecific while the interactions with DPPG monolayer are significant, attractive, and specific. These results are in accord with the fact that antimicrobial peptides disrupt bacteria membranes (negative) while no significant effect on the host membranes (neutral) is observed. No such discrimination was revealed from the compression isotherms. The latter indicate that squeezing the penetrant out of the monolayer upon compression does not allow for establishing the penetration equilibrium, so the monolayer remains supersaturated with the penetrant and shows an under-equilibrium orientation within the entire compression range, practically.
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7
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López-Montero I, Mateos-Gil P, Sferrazza M, Navajas PL, Rivas G, Vélez M, Monroy F. Active membrane viscoelasticity by the bacterial FtsZ-division protein. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:4744-4753. [PMID: 22329688 DOI: 10.1021/la204742b] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
At the early stages of the division process in Escherichia coli, the protein FtsZ forms a septal ring at the midcell. This Z-ring causes membrane constriction during bacterial division. The Z-ring associates to the lipid membrane through several membrane proteins, ZipA among them. Here, a simplified FtsZ-ZipA model was reconstituted onto Langmuir monolayers based in E. coli polar lipid extract. Brewster angle and atomic force microscopy have revealed membrane FtsZ-polymerization upon GTP hydrolysis. The compression viscoelasticity of these monolayers has been also investigated. The presence of protein induced softening and fluidization with respect to the bare lipid membrane. An active mechanism, based on the internal forces stressed by FtsZ filaments and transduced to the lipid membrane by ZipA, was suggested to underlie the observed behavior.
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Affiliation(s)
- Iván López-Montero
- Departamento de Química Física I, Universidad Complutense de Madrid, Madrid, Spain
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8
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Caro AL, Rodríguez Niño MR, Rodríguez Patino JM. Dynamics of penetration of dipalmitoyl-phosphatidyl-choline (DPPC) monolayers by β-casein. Colloids Surf A Physicochem Eng Asp 2009. [DOI: 10.1016/j.colsurfa.2009.03.056] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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9
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Pérez-López S, Nieto-Suárez M, Mestres C, Alsina MA, Haro I, Vila-Romeu N. Behaviour of a peptide sequence from the GB virus C/hepatitis G virus E2 protein in Langmuir monolayers: Its interaction with phospholipid membrane models. Biophys Chem 2009; 141:153-61. [DOI: 10.1016/j.bpc.2009.01.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Revised: 01/21/2009] [Accepted: 01/22/2009] [Indexed: 10/21/2022]
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10
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Reis P, Holmberg K, Watzke H, Leser ME, Miller R. Lipases at interfaces: a review. Adv Colloid Interface Sci 2009; 147-148:237-50. [PMID: 18691682 DOI: 10.1016/j.cis.2008.06.001] [Citation(s) in RCA: 492] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Revised: 06/20/2008] [Accepted: 06/23/2008] [Indexed: 11/20/2022]
Abstract
Lipases are acyl hydrolases that play a key role in fat digestion by cleaving long-chain triglycerides into polar lipids. Due to an opposite polarity between the enzyme (hydrophilic) and their substrates (lipophilic), lipase reaction occurs at the interface between the aqueous and the oil phases. Hence, interfaces are the key spots for lipase biocatalysis and an appropriate site for modulating lipolysis. Surprisingly enough, knowledge about the effects of the interfacial composition on lipase catalysis is still limited and only described by the term "interfacial quality". Recent systematic studies based on a biophysical approach allowed for the first time to show the effects of the interfacial microenvironment on lipase catalysis. These studies demonstrate that lipase activity as a function of interfacial composition is more attributed to substrate inaccessibility rather than to enzyme denaturation or inactivation, as it is often hypothesized. A detailed analysis of the interfacial properties of all compounds involved in triglyceride digestion revealed that lipolysis is a self-regulated reaction. This feedback mechanism can be explored as a new avenue to control lipase catalysis. To substantiate this hypothesis, oil hydrolysis in a model gastro-intestinal system was performed, which can be seen as an interfacial engineering approach to enzyme reactivity control. The presented characterization of the interfacial composition and its consequences provide a new approach for the understanding of lipase reactions at interfaces with direct impact on biotechnological and health care applications.
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Affiliation(s)
- P Reis
- Nestlé Research Center, CH-1000 Lausanne 26, Switzerland
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11
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Krägel J, Derkatch SR, Miller R. Interfacial shear rheology of protein-surfactant layers. Adv Colloid Interface Sci 2008; 144:38-53. [PMID: 18823871 DOI: 10.1016/j.cis.2008.08.010] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The shear rheology of adsorbed or spread layers at air/liquid and liquid/liquid phase boundaries is relevant in a wide range of technical applications such as mass transfer, monolayers, foaming, emulsification, oil recovery, or high speed coating. Interfacial shear rheological properties can provide important information about interactions and molecular structure in the interfacial layer. A variety of measuring techniques have been proposed in the literature to measure interfacial shear rheological properties and have been applied to pure protein or mixed protein adsorption layers at air/water or oil/water interfaces. Such systems play for example an important role as stabilizers in foams and emulsions. The aim of this contribution is to give a literature overview of interfacial shear rheological studies of pure protein and protein/surfactant mixtures at liquid interfaces measured with different techniques. Techniques which utilize the damping of waves, spectroscopic or AFM techniques and all micro-rheological techniques will not discuss here.
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Affiliation(s)
- J Krägel
- Max Planck Institute of Colloids and Interfaces, Potsdam-Golm, Germany.
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12
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Daschner De Tercero M, Abbott NL. Ordering Transitions in Liquid Crystals Permit Imaging of Spatial and Temporal Patterns Formed by Proteins Penetrating into Lipid-Laden Interfaces. CHEM ENG COMMUN 2008; 196:234-251. [PMID: 23671353 DOI: 10.1080/00986440802290060] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Recent studies have reported that full monolayers of L-α-dilaurylphosphatidylcholine (L-DLPC) and D-α-dipalmitoylphosphatidylcholine (D-DPPC) formed at interfaces between thermotropic liquid crystals (LCs) and aqueous phases lead to homeotropic (perpendicular) orientations of nematic LCs and that specific binding of proteins to these interfaces (such as phospholipase A2 binding to D-DPPC) can trigger orientational ordering transitions in the liquid crystals. We report on the nonspecific interactions of proteins with aqueous-LC interfaces decorated with partial monolayer coverage of L-DLPC. Whereas nonspecific interactions of four proteins (cytochrome c, bovine serum albumin,immunoglobulins, and neutravidin) do not perturb the ordering of the LC when a full monolayer of L-DLPC is assembled at the aqueous-LC interface, we observe patterned orientational transitions in the LC that reflect penetration of proteins into the interface of the LC with partial monolayer coverage of L-DLPC. The spatial patterns formed by the proteins and lipids at the interface are surprisingly complex, and in some cases the protein domains are found to compartmentalize lipid within the interfaces. These results suggest that phospholipid-decorated interfaces between thermotropic liquid crystals and aqueous phases offer the basis of a simple and versatile tool to study the spatial organization and dynamics ofprotein networks formed at mobile, lipid-decorated interfaces.
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Affiliation(s)
- Maren Daschner De Tercero
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison,Wisconsin, USA
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13
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Reis P, Holmberg K, Miller R, Krägel J, Grigoriev DO, Leser ME, Watzke HJ. Competition between lipases and monoglycerides at interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:7400-7407. [PMID: 18547084 DOI: 10.1021/la800531y] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Tensiometry (the pendant drop technique), interfacial shear rheology, and ellipsometry have been used to study the effect of polar lipids that are generated during fat digestion on the behavior of lipases at the oil-water interface. Both Sn-1,3 regiospecific and nonregiospecific lipases have been used, and a noncatalytically active protein, beta-lacloglobulin, has been used as reference in the interfacial shear rheology experiments. The results from the pendant drop measurements and the interfacial rheology studies were in agreement with each other and demonstrated that the Sn-2 monoglyceride, which is one of the lipolysis products generated when a Sn-1,3 regiospecific lipase catalyzes triglyceride hydrolysis, is very interfacially active and efficiently expels the enzyme from the interface. Ellipsometry conducted at the liquid-liquid interface showed that the lipase forms a sublayer in the aqueous phase, just beneath the monoglyceride-covered interface. Sn-1/3 monoglycerides do not behave this way because they are rapidly degraded to fatty acid and glycerol and the fatty acid (or the fatty acid salt) does not have enough interfacial activity to expel the lipase from the interface. Since the lipases present in the gastrointestinal tract are highly Sn-1,3 regiospecific, we believe that the results obtained can be transferred to the in vivo situation. The formation of stable and amphiphilic Sn-2 monoglycerides can be seen as a self-regulatory process for fat digestion.
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Affiliation(s)
- Pedro Reis
- Nestle Research Center, CH-1000 Lausanne 26, Switzerland
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14
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Duncan SL, Larson RG. Comparing experimental and simulated pressure-area isotherms for DPPC. Biophys J 2008; 94:2965-86. [PMID: 18199666 PMCID: PMC2275714 DOI: 10.1529/biophysj.107.114215] [Citation(s) in RCA: 163] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2007] [Accepted: 12/03/2007] [Indexed: 11/18/2022] Open
Abstract
Although pressure-area isotherms are commonly measured for lipid monolayers, it is not always appreciated how much they can vary depending on experimental factors. Here, we compare experimental and simulated pressure-area isotherms for dipalmitoylphosphatidylcholine (DPPC) at temperatures ranging between 293.15 K and 323.15 K, and explore possible factors influencing the shape and position of the isotherms. Molecular dynamics simulations of DPPC monolayers using both coarse-grained (CG) and atomistic models yield results that are in rough agreement with some of the experimental isotherms, but with a steeper slope in the liquid-condensed region than seen experimentally and shifted to larger areas. The CG lipid model gives predictions that are very close to those of atomistic simulations, while greatly improving computational efficiency. There is much more variation among experimental isotherms than between isotherms obtained from CG simulations and from the most refined simulation available. Both atomistic and CG simulations yield liquid-condensed and liquid-expanded phase area compressibility moduli that are significantly larger than those typically measured experimentally, but compare well with some experimental values obtained under rapid compression.
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Affiliation(s)
- Susan L Duncan
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan, USA
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15
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Surface rheology and phase transitions of monolayers of phospholipid/cholesterol mixtures. Biophys J 2008; 94:3924-34. [PMID: 18234814 DOI: 10.1529/biophysj.107.104851] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The dynamic surface elasticity and the surface dilational viscosity of three binary phospholipid/cholesterol mixtures were determined with axisymmetric drop shape analysis on a harmonically oscillating pendent drop. Dipalmitoylphosphatidylcholine, dimyristoylphosphatidylcholine, and dioleoylphosphatidylcholine were used to explore the rheological properties and phase transitions of mixtures of saturated and unsaturated phospholipids with cholesterol. The growth rates for surface dilational viscosity and dynamic elasticity are parallel for all film pressures studied. Characteristic breaks and plateaus could be found for these growth rates, indicating phase transitions. For dipalmitoylphosphatidylcholine/cholesterol and dimyristoylphosphatidylcholine/cholesterol mixtures, phase diagrams with six regions separated by phase boundaries were found, which are in good agreement with phase transitions reported in the literature for static measurements of isotherms and isobars on a Langmuir film balance and from fluorescence microscopy. Some phase boundaries were only found by dynamic, but not by static, elasticity measurements. Imaging methods revealed phase separations produced by the formation of condensed stoichiometric complexes leading to micron-sized and mostly circular domains. The effects of these complexes on monolayer rheology in liquid/liquid phases is described. Furthermore, liquid/solid and solid phase transitions are discussed.
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16
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Barlow DJ, Hollinshead CM, Harvey RD, Kudsiova L, Lawrence MJ. Memory effects of monolayers and vesicles formed by the non-ionic surfactant, 2C18E12. J Colloid Interface Sci 2007; 316:741-50. [PMID: 17825312 DOI: 10.1016/j.jcis.2007.08.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2007] [Revised: 08/02/2007] [Accepted: 08/06/2007] [Indexed: 11/25/2022]
Abstract
The behaviour of monolayers and bilayers formed by the dialkyl chain non-ionic surfactant, 1,2-di-O-octadecyl-rac-glycerol-3-omega-methoxydodecaethylene glycol (2C(18)E(12)) in water at 297 K has been investigated. Using a surface film balance (or Langmuir trough) the compression-expansion cycle of the 2C(18)E(12) monolayer was found to be reversible when compressed to surface pressures (pi) less than 42 mN m(-1). Compression of 2C(18)E(12) monolayer to pi greater than 42 mN m(-1) above this resulted in a considerable hysteresis upon expansion with the pi remaining high relative to that obtained upon compression, suggesting a time/pressure dependent re-arrangement of 2C(18)E(12) molecules in the film. Morphology of the 2C(18)E(12) monolayer, investigated using Brewster angle microscopy, was also found to depend upon monolayer history. Bright, randomly dispersed domains of 2C(18)E(12) of approximately 5 mum in size were observed during compression of the monolayer to pi less than 42 mN m(-1). At pi of 42 mN m(-1) and above, the surfactant film appeared to be almost completely 'solid-like.' Regardless of the extent of compression of the monolayer film, expansion of the film caused formation of chains or 'necklaces' of individual surfactant domains, with the extent of chain formation dependent upon pressure of compression of the monolayer and the length of time held at that pressure. Irreversible effects on 2C(18)E(12) vesicle size were also seen upon temperature cycling the vesicles through their liquid-crystalline phase transition temperature with vesicles shrinking in size and not returning to their original size upon standing at 298 K for periods of more than 24 h. No comparable hysteresis, time, pressure or temperature effects were observed with the monolayer or vesicles formed by the corresponding phospholipid, disteaorylphosphatidylcholine, under identical conditions. The effects observed with 2C(18)E(12) are attributed to the ability of the polyoxyethylene head group to dehydrate and intrude into the hydrophobic chain region of the mono- and bilayers. These studies have important implications for the use of the vesicles formed by 2C(18)E(12) as drug delivery vehicles.
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Affiliation(s)
- D J Barlow
- Department of Pharmacy, Franklin Wilkins Building, King's College London, 150 Stamford Street, London SE1 9NH, UK
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17
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Vrânceanu M, Winkler K, Nirschl H, Leneweit G. Surface rheology of monolayers of phospholipids and cholesterol measured with axisymmetric drop shape analysis. Colloids Surf A Physicochem Eng Asp 2007. [DOI: 10.1016/j.colsurfa.2007.06.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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18
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Rodríguez Patino JM, Cejudo Fernández M, Carrera Sánchez C, Rodríguez Niño MR. Structural and shear characteristics of adsorbed sodium caseinate and monoglyceride mixed monolayers at the air–water interface. J Colloid Interface Sci 2007; 313:141-51. [PMID: 17509606 DOI: 10.1016/j.jcis.2007.04.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2007] [Revised: 04/11/2007] [Accepted: 04/12/2007] [Indexed: 11/23/2022]
Abstract
The structural and shear characteristics of mixed monolayers formed by an adsorbed Na-caseinate film and a spread monoglyceride (monopalmitin or monoolein) on the previously adsorbed protein film have been analyzed. Measurements of the surface pressure (pi)-area (A) isotherm and surface shear viscosity (eta(s)) were obtained at 20 degrees C and at pH 7 in a modified Wilhelmy-type film balance. The structural and shear characteristics of the mixed films depend on the surface pressure and on the composition of the mixed film. At surface pressures lower than the equilibrium surface pressure of Na-caseinate (at pi<pi(e)(CS)), both Na-caseinate and monoglyceride coexist at the interface, with a structural polymorphism or a liquid expanded structure due to the presence of monopalmitin or monoolein in the mixture, respectively. At higher surface pressures, collapsed Na-caseinate residues may be displaced from the interface by monoglyceride molecules. For a Na-caseinate-monopalmitin mixed film the eta(s) value varies greatly with the surface pressure (or surface density) of the mixed monolayer at the interface. In general, the greater the surface pressure, the greater are the values of eta(s). However, the values of eta(s) for a Na-caseinate-monoolein mixed monolayer are very low and practically do not depend on the surface pressure. The collapsed Na-caseinate residues displaced from the interface by monoglyceride molecules at pi>pi(e)(CS) have important repercussions on the shear characteristics of the mixed films.
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Affiliation(s)
- Juan M Rodríguez Patino
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, Seville, Spain.
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Fernández MC, Sánchez CC, Rodríguez Niño MR, Rodríguez Patino JM. Monoglycerides and beta-lactoglobulin adsorbed films at the air-water interface. structure, microscopic imaging, and shear characteristics. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:7178-88. [PMID: 17511488 DOI: 10.1021/la7003497] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
In this work we have analyzed the structural, topographical, and shear characteristics of mixed monolayers formed by adsorbed beta-lactoglobulin (beta-lg) and spread monoglyceride (monopalmitin or monoolein) on a previously adsorbed protein film. Measurements of the surface pressure (pi)-area (A) isotherm, Brewster angle microscopy (BAM), and surface shear characteristics were obtained at 20 degrees C and at pH 7 in a modified Wilhelmy-type film balance. The pi-A isotherm and BAM images deduced for adsorbed beta-lactoglobulin-monoglyceride mixed films at pi lower than the equilibrium surface pressure of beta-lactoglobulin (pi(e)(beta-lg)) indicate that beta-lactoglobulin and monoglyceride coexist at the interface. However, the interactions between protein and monoglyceride are somewhat weak. At higher surface pressures (at pi > or = pi(e)(beta-lg)) a protein displacement by the monoglyceride from the interface takes place. The surface shear viscosity (eta(s)) of mixed films is very sensitive to protein-monoglyceride interactions and displacement as a function of monolayer composition (protein/monoglyceride fraction) and surface pressure. Shear can induce change in the morphology of monoglyceride and beta-lactoglobulin domains, on the one hand, and segregation between domains of the film-forming components on the other hand. In addition, the displacement of beta-lactoglobulin by the monoglycerides is facilitated under shear conditions.
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Affiliation(s)
- Marta Cejudo Fernández
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, C/. Prof. García González 1, 41012-Seville, Spain
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20
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Fernández MC, Sánchez CC, Rodríguez Niño MR, Rodríguez Patino JM. The Effect of Monoglycerides on Structural and Topographical Characteristics of Adsorbed β-Casein Films at the Air−Water Interface. Biomacromolecules 2006; 7:507-14. [PMID: 16471923 DOI: 10.1021/bm050733h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effect of monoglycerides (monopalmitin and monoolein) on the structural and topographical characteristics of beta-casein adsorbed film at the air-water interface has been analyzed by means of surface pressure (pi)-area (A) isotherms and Brewster angle microscopy (BAM). At surface pressures lower than that for the beta-casein collapse (pi(c)(beta-casein)), attractive interactions between beta-casein and monoglycerides were observed. At higher surface pressures, the collapsed beta-casein is partially displaced from the interface by monoglycerides. However, beta-casein displacement by monoglycerides is not quantitative at the monoglyceride concentrations studied in this work. From the results derived from these experiments, we have concluded that interactions, miscibility, and displacement of proteins by monoglycerides in adsorbed mixed monolayers at the air-water interface depend on the particular protein-monoglyceride system, the interactions between film-forming components being higher for adsorbed than for spread films. The adsorbed films are more segregated than spread films, and both collapsed protein domains and monoglyceride domains in adsorbed films are smaller than for spread films.
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Affiliation(s)
- Marta Cejudo Fernández
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, C/. Prof. García González 1, 41012-Seville, Spain
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21
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Interactive Adsorption Behavior of β-Lactoglobulin and Linoleate at a 316L Stainless Steel Surface. ACTA ACUST UNITED AC 2005. [DOI: 10.1149/1.1836115] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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22
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Mackie AR. Structure of adsorbed layers of mixtures of proteins and surfactants. Curr Opin Colloid Interface Sci 2004. [DOI: 10.1016/j.cocis.2004.08.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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23
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Patino JMR, Fernández MC. Structural and topographical characteristics of adsorbed WPI and monoglyceride mixed monolayers at the air-water interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:4515-22. [PMID: 15969160 DOI: 10.1021/la036190j] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
In this work we have analyzed the structural and topographical characteristics of mixed monolayers formed by an adsorbed whey protein isolate (WPI) and a spread monoglyceride monolayer (monopalmitin or monoolein) on the previously adsorbed protein film. Measurements of the surface pressure (pi)-area (A) isotherm were obtained at 20 degrees C and at pH 7 for protein-adsorbed films from water in a Wilhelmy-type film balance. Since the surface concentration (1/A) is actually unknown for the adsorbed monolayer, the values were derived by assuming that the A values for adsorbed and spread monolayers were equal at the collapse point of the mixed film. The pi-A isotherm deduced for adsorbed WPI monolayer in this work is practically the same as that obtained directly by spreading. For WPI-monoglyceride mixed films, the pi-A isotherms for adsorbed and spread monolayers at pi higher than the equilibrium surface pressure of WPI are practically coincident, a phenomenon which may be attributed to the protein displacement by the monoglyceride from the interface. At lower surface pressures, WPI and monoglyceride coexist at the interface and the adsorbed and spread pi-A isotherms (i.e., the monolayer structure of the mixed films) are different. Monopalmitin has a higher capacity than monoolein for the displacement of protein from the air-water interface. However, some degree of interactions exists between proteins and monoglycerides and these interactions are higher for adsorbed than for spread films. The topography of the monolayer corroborates these conclusions.
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Affiliation(s)
- Juan M Rodríguez Patino
- Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, C/. Prof. García González 1, 41012-Seville, Spain.
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Caseli L, Zaniquelli MED, Furriel RPM, Leone FA. Adsorption of detergent-solubilized and phospholipase C-solubilized alkaline phosphatase at air/liquid interfaces. Colloids Surf B Biointerfaces 2003. [DOI: 10.1016/s0927-7765(03)00104-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Chou TH, Chu IM. Behavior of DSPC/DSPE-PEG2000 mixed monolayers at the air/water interface. Colloids Surf A Physicochem Eng Asp 2002. [DOI: 10.1016/s0927-7757(02)00280-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Interaction of paclitaxel with DSPC in monolayers at the air/water interface at different temperatures. Colloids Surf B Biointerfaces 2002. [DOI: 10.1016/s0927-7765(01)00303-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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27
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Caseli L, Zaniquelli MED, Furriel RPM, Leone FA. Enzymatic activity of alkaline phosphatase adsorbed on dimyristoylphosphatidic acid Langmuir–Blodgett films. Colloids Surf B Biointerfaces 2002. [DOI: 10.1016/s0927-7765(01)00302-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Miller R, Fainerman VB, Makievski AV, Krägel J, Grigoriev DO, Kazakov VN, Sinyachenko OV. Dynamics of protein and mixed protein/surfactant adsorption layers at the water/fluid interface. Adv Colloid Interface Sci 2000; 86:39-82. [PMID: 10798350 DOI: 10.1016/s0001-8686(00)00032-4] [Citation(s) in RCA: 369] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The adsorption behaviour of proteins and systems mixed with surfactants of different nature is described. In the absence of surfactants the proteins mainly adsorb in a diffusion controlled manner. Due to lack of quantitative models the experimental results are discussed partly qualitatively. There are different types of interaction between proteins and surfactant molecules. These interactions lead to protein/surfactant complexes the surface activity and conformation of which are different from those of the pure protein. Complexes formed with ionic surfactants via electrostatic interaction have usually a higher surface activity, which becomes evident from the more than additive surface pressure increase. The presence of only small amounts of ionic surfactants can significantly modify the structure of adsorbed proteins. With increasing amounts of ionic surfactants, however, an opposite effect is reached as due to hydrophobic interaction and the complexes become less surface active and can be displaced from the interface due to competitive adsorption. In the presence of non-ionic surfactants the adsorption layer is mainly formed by competitive adsorption between the compounds and the only interaction is of hydrophobic nature. Such complexes are typically less surface active than the pure protein. From a certain surfactant concentration of the interface is covered almost exclusively by the non-ionic surfactant. Mixed layers of proteins and lipids formed by penetration at the water/air or by competitive adsorption at the water/chloroform interface are formed such that at a certain pressure the components start to separate. Using Brewster angle microscopy in penetration experiments of proteins into lipid monolayers this interfacial separation can be visualised. A brief comparison of the protein adsorption at the water/air and water/n-tetradecane shows that the adsorbed amount at the water/oil interface is much stronger and the change in interfacial tension much larger than at the water/air interface. Also some experimental data on the dilational elasticity of proteins at both interfaces measured by a transient relaxation technique are discussed on the basis of the derived thermodynamic model. As a fast developing field of application the use of surface tensiometry and rheometry of mixed protein/surfactant mixed layers is demonstrated as a new tool in the diagnostics of various diseases and for monitoring the progress of therapies.
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Affiliation(s)
- R Miller
- MPI für Kolloid- und Grenzflächenforschung, Golm, Germany.
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