Protection of liposomes against fusion during drying by oligosaccharides is not predicted by the calorimetric glass transition temperatures of the dry sugars
In previous studies, it has been suggested that chilling induced activation of human platelets is related to a lipid phase transition seen in membrane lipids. Those studies showed a single, surprisingly cooperative transition in human... more
In previous studies, it has been suggested that chilling induced activation of human platelets is related to a lipid phase transition seen in membrane lipids. Those studies showed a single, surprisingly cooperative transition in human platelets, as determined by Fourier transform infrared (FTIR) spectroscopy, findings that are confirmed here with calorimetric measurements. Such transitions have now been studied in membrane fractions obtained from the platelets and it is reported that all fractions and purified phospholipids show similar transitions. In order to obtain these data it was necessary to develop means for separating these fractions. Therefore, a novel method for isolation and separation of dense tubular system (DTS) and plasma membranes in human platelets is described here. Lipid analysis showed that phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were the dominant phospholipids in both fractions, whereas cholesterol and sphingomyelin (SM) were predominantly located in the plasma membranes. Thermotropic phase transitions in the two membrane fractions, determined by differential scanning calorimetry (DSC) and FTIR spectroscopy were found to occur at about 15 degrees C, similar to the Tm of intact human platelets. These data are discussed in relation to the role of the DTS and plasma membranes in the cold-induced activation of human platelets.
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Research Interests: Biophysics, Chemistry, Biophysical Chemistry, Medicine, Ion Channels, and 14 moreBiological Sciences, Permeability, Physical sciences, Liposomes, Peptides, CHEMICAL SCIENCES, Protein Secondary Structure Prediction, Fourier transform infrared spectroscopy, Lipid bilayers, Lipid Bilayer, Electric Conductivity, Protons, Gramicidin, and In Vitro Techniques
Fourier-transform infrared spectroscopy (FTIR) was used to study the hydrogen-bonding interactions that take place in vitrified carbohydrates of different chain lengths. The band position of the OH stretching band (vOH) and the shift in... more
Fourier-transform infrared spectroscopy (FTIR) was used to study the hydrogen-bonding interactions that take place in vitrified carbohydrates of different chain lengths. The band position of the OH stretching band (vOH) and the shift in band position as a function of temperature were determined from the FTIR spectra as indicators for the length and strength of intermolecular hydrogen bonds, respectively. Differential scanning calorimetry (DSC) was used to corroborate the FTIR studies and to measure the change in heat capacity (delta C(p)) that is associated with the glass transition. We found that with increasing T(g), the band position of vOH increases, the wavenumber-temperature coefficient of vOH in the glassy state, WTC(g), increases, whereas (delta C(p) decreases. The positive correlation that was found between vOH and the glass transition temperature, T(g), indicates that the length of the hydrogen bonds increases with increasing T(g). The increase in WTC(g) with increasing T(g) indicates that the average strength of hydrogen bonding decreases with increasing T(g). This implies that oligo- and polysaccharides (high T(g)) have a greater degree of freedom to rearrange hydrogen bonds during temperature changes than monosaccharides (low T(g)). Interestingly, WTC(g) and delta C(p) showed a negative linear correlation, indicating that the change in heat capacity during the glass transition is associated with the strength of the hydrogen-bonding network in the glassy state. Furthermore, we report that introduction of poly-L-lysine in glassy sugar matrices decreases the average length of hydrogen bonds, irrespective of the size of the carbohydrate. Palmitoyl-oleoyl-phosphatidylcholine (POPC) vesicles were found to only interact with small sugars and not with dextran.
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... Ann E. Oliver and David W. Deamer Dept. ... FTIR spectroscopy was used to probe the secondary structure of peptides by comparison of the carbonyl stretching (amide I) region (Byler and SUS!, 1986; 1988; Susi and Byler, 1983). ...
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Fourier-transform infrared spectroscopy (FTIR) was used to study the hydrogen-bonding interactions that take place in vitrified carbohydrates of different chain lengths. The band position of the OH stretching band (vOH) and the shift in... more
Fourier-transform infrared spectroscopy (FTIR) was used to study the hydrogen-bonding interactions that take place in vitrified carbohydrates of different chain lengths. The band position of the OH stretching band (vOH) and the shift in band position as a function of temperature were determined from the FTIR spectra as indicators for the length and strength of intermolecular hydrogen bonds, respectively. Differential scanning calorimetry (DSC) was used to corroborate the FTIR studies and to measure the change in heat capacity (delta C(p)) that is associated with the glass transition. We found that with increasing T(g), the band position of vOH increases, the wavenumber-temperature coefficient of vOH in the glassy state, WTC(g), increases, whereas (delta C(p) decreases. The positive correlation that was found between vOH and the glass transition temperature, T(g), indicates that the length of the hydrogen bonds increases with increasing T(g). The increase in WTC(g) with increasing T(g) indicates that the average strength of hydrogen bonding decreases with increasing T(g). This implies that oligo- and polysaccharides (high T(g)) have a greater degree of freedom to rearrange hydrogen bonds during temperature changes than monosaccharides (low T(g)). Interestingly, WTC(g) and delta C(p) showed a negative linear correlation, indicating that the change in heat capacity during the glass transition is associated with the strength of the hydrogen-bonding network in the glassy state. Furthermore, we report that introduction of poly-L-lysine in glassy sugar matrices decreases the average length of hydrogen bonds, irrespective of the size of the carbohydrate. Palmitoyl-oleoyl-phosphatidylcholine (POPC) vesicles were found to only interact with small sugars and not with dextran.
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Arbutin is a glycosylated hydroquinone found at high concentrations in certain plants capable of surviving extreme and sustained dehydration. In this paper, we examine a potential role of this molecule in anhydrobiosis. We have studied... more
Arbutin is a glycosylated hydroquinone found at high concentrations in certain plants capable of surviving extreme and sustained dehydration. In this paper, we examine a potential role of this molecule in anhydrobiosis. We have studied its effects on the physical properties of phospholipids and on preservation of liposomes during drying. Arbutin depresses the gel to liquid crystalline phase transition temperature of dry phospholipids, as measured by differential scanning calorimetry, with a pattern similar to that seen in phospholipids dried with the disaccharide trehalose. Unlike trehalose, however, arbutin does not protect dry liposomes from leaking their contents. Also, using Fourier transform infrared spectroscopy, we found an increase in the vibrational frequency of the phosphate asymmetric stretch in partially hydrated phospholipids in the presence of arbutin. Trehalose, by contrast, depresses the frequency of the phosphate in dry phospholipids, indicating that the modes of in...
Research Interests: Physical Chemistry, Phospholipids, Crystallization, Enzyme Inhibitors, Biological Sciences, and 15 moreDifferential scanning calorimetry, Physical sciences, Temperature, Liposomes, Desiccation, Trehalose, Phase transition, Enzyme, Gels, Physical Properties, Liquid Crystalline, Fourier transform infrared, Thin Layer, Structural similarity, and Arbutin
Fourier-transform infrared spectroscopy (FTIR) was used to study the hydrogen-bonding interactions that take place in vitrified carbohydrates of different chain lengths. The band position of the OH stretching band (vOH) and the shift in... more
Fourier-transform infrared spectroscopy (FTIR) was used to study the hydrogen-bonding interactions that take place in vitrified carbohydrates of different chain lengths. The band position of the OH stretching band (vOH) and the shift in band position as a function of temperature were determined from the FTIR spectra as indicators for the length and strength of intermolecular hydrogen bonds, respectively. Differential scanning calorimetry (DSC) was used to corroborate the FTIR studies and to measure the change in heat capacity (delta C(p)) that is associated with the glass transition. We found that with increasing T(g), the band position of vOH increases, the wavenumber-temperature coefficient of vOH in the glassy state, WTC(g), increases, whereas (delta C(p) decreases. The positive correlation that was found between vOH and the glass transition temperature, T(g), indicates that the length of the hydrogen bonds increases with increasing T(g). The increase in WTC(g) with increasing T(...
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... nitrogen. The cells were grown in Dul-becco's modified Eagle medium (DMEM)-low glucose, with 10% FBS (Hyclone, Logan, UT) at 37°C with 5% CO2 and 90% RH, with an initial plating density of approximantely 5500 cells/cm2. ...
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The objective of this study was to determine if trehalose can effectively enhance the viability and storage lifetime of Rhizobium tropici and Rhizobium etli after lyophilization as compared to the traditional protective combination of... more
The objective of this study was to determine if trehalose can effectively enhance the viability and storage lifetime of Rhizobium tropici and Rhizobium etli after lyophilization as compared to the traditional protective combination of sucrose and peptone. Two strains of bean-nodulating rhizobia were effectively preserved in the lyophilized state by 100 mM trehalose, and survived for at least 12 days, even when stored under non-ideal conditions. Trehalose provided better protection than the sucrose/peptone combination. When protective excipients were introduced inside the cells, strain CFN 42 was more sensitive to the type of additive used than strain CIAT 899, probably because CIAT 899 produces beta (1-2) glucan, which may have a protective effect. beta (1-2) glucan combined with sucrose protected better than trehalose against leakage from freeze-dried liposomes, but by itself it had no protective capability. There was a high level of unfrozen water associated with the hydrated gluc...
Borrowing principles of anhydrobiosis, we have developed a technique for self-assembling proteolipid-supported membranes on demand--simply by adding water. Intact lipid- and proteolipid vesicles dispersed in aqueous solutions of... more
Borrowing principles of anhydrobiosis, we have developed a technique for self-assembling proteolipid-supported membranes on demand--simply by adding water. Intact lipid- and proteolipid vesicles dispersed in aqueous solutions of anhydrobiotic trehalose are vitrified on arbitrary substrates, producing glassy coats encapsulating biomolecules. Previous efforts establish that these carbohydrate coats arrest molecular mobilities and preserve native conformations and aggregative states of the embedded biomolecules, thereby enabling long-term storage. Subsequent rehydration, even after an extended period of time (e.g., weeks), devitrifies sugar--releasing the cargo and unmasking the substrate surface--thus triggering substrate-mediated vesicle fusion in real time, producing supported membranes. Using this method, arrays of membranes, including those functionalized with membrane proteins, can be readily produced in situ by spatially addressing vitrification using common patterning tools--useful for multiplexed or stochastic sensing and assaying of target interactions with the fluid and functional membrane surface.
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Research Interests: Zoology and Integrative
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Research Interests: Cryobiology, Membranes, Cryopreservation, Lipids, FTIR, and 15 moreAnimals, Male, Cell Death, Membrane Lipids, Cell Viability, Medical Physiology, Fourier transform infrared spectroscopy, Free Fatty Acid, Membrane Protein, Freezing, Cell Survival, Membrane Fluidity, Biochemistry and cell biology, Adenocarcinoma, and Liquid Crystalline
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... Ann E. Oliver and David W. Deamer Dept. ... FTIR spectroscopy was used to probe the secondary structure of peptides by comparison of the carbonyl stretching (amide I) region (Byler and SUS!, 1986; 1988; Susi and Byler, 1983). ...
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Effective stabilization of nucleated cells for dry storage would be a transformative development in the field of cell-based biosensors and biotechnologic devices, as well as regenerative medicine and other areas in which stem cells have... more
Effective stabilization of nucleated cells for dry storage would be a transformative development in the field of cell-based biosensors and biotechnologic devices, as well as regenerative medicine and other areas in which stem cells have clinical utility. Ultimately, the tremendous promise of cell-based products will only be fully realized when stable long-term storage becomes available without the use of liquid nitrogen and bulky, energetically expensive freezers. Significant progress has been made over the last 10 years toward this goal, but obstacles still remain. Loading cells with the protective disaccharide trehalose has been achieved by several different techniques and has been shown to increase cell survival at low water contents. Likewise, the protective effect of heat shock proteins and other compounds have also been explored alone and in combination with trehalose. In some cases, the benefit of these molecules is seen not initially upon rehydration, but over time during ce...
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Fourier-transform infrared spectroscopy (FTIR) was used to study the hydrogen-bonding interactions that take place in vitrified carbohydrates of different chain lengths. The band position of the OH stretching band (νOH) and the shift in... more
Fourier-transform infrared spectroscopy (FTIR) was used to study the hydrogen-bonding interactions that take place in vitrified carbohydrates of different chain lengths. The band position of the OH stretching band (νOH) and the shift in band position as a function of temperature were determined from the FTIR spectra as indicators for the length and strength of intermolecular hydrogen bonds, respectively. Differential
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Page 1. CELL PRESERVATION TECHNOLOGY Volume 2, Number 1, 2004 © Mary Ann Liebert, Inc. Loading Human Mesenchymal Stem Cells with Trehalose by Fluid-Phase Endocytosis ANN E. OLIVER,1,2 KAMRAN JAMIL,1,3 JOHN H. CROWE,1,2 and FERN TABLIN1,3... more
Page 1. CELL PRESERVATION TECHNOLOGY Volume 2, Number 1, 2004 © Mary Ann Liebert, Inc. Loading Human Mesenchymal Stem Cells with Trehalose by Fluid-Phase Endocytosis ANN E. OLIVER,1,2 KAMRAN JAMIL,1,3 JOHN H. CROWE,1,2 and FERN TABLIN1,3 ...
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... Ann E. Oliver*, Lois M. Crowe and John H. Crowe Section of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA ... liquid water can lead to catastrophic membrane leakage, which m biological tissue, results... more
... Ann E. Oliver*, Lois M. Crowe and John H. Crowe Section of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA ... liquid water can lead to catastrophic membrane leakage, which m biological tissue, results in cell death (Crowe, et al, 1989b, Leslie et al ...