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Comparative Biochemistry and... May 1972
Phospholipid patterns of two symbiote-harbouring weevils, the rice weevil, Sitophilus oryzae L., and the corn weevil, Sitophilus zeamais (Mots.) (Coleoptera: Curculionidae).
Topics: Animals; Chromatography, Thin Layer; Coleoptera; Lipids; Lysophosphatidylcholines; Phosphatidylcholines; Phosphatidylethanolamines; Phospholipids; Species Specificity; Spectrophotometry; Symbiosis
PubMed: 5075766
DOI: 10.1016/0305-0491(72)90071-5 -
Biochimica Et Biophysica Acta Jan 1980The major phospholipid exchange protein from bovine brain catalyzes the transfer of phosphatidylinositol and phosphatidylcholine between rat liver microsomes and...
The major phospholipid exchange protein from bovine brain catalyzes the transfer of phosphatidylinositol and phosphatidylcholine between rat liver microsomes and sonicated liposomes. The effect of liposomal lipid composition on the transfer of these phospholipids has been investigated. Standard liposomes contained phosphatidylcholine-phosphatidic acid (98 : 2, mol%); in general, phosphatidylcholine was substituted by various positively charged, negatively charged, or zwitterionic lipids. The transfer of phosphatidylinositol was essentially unaffected by the incorporation into liposomes of phosphatidic acid, phosphatidylserine, or phosphatidylglycerol (5--20 mol%) but strongly depressed by the incorporation of stearylamine (10--40 mol%). Marked stimulation (2--4-fold) of transfer activity was observed into liposomes containing phosphatidylethanolamine (2--40 mol%). The inclusion of sphingomyelin in the acceptor liposomes gave mixed results: stimulation at low levels (2--10 mol%) and inhibition at higher levels (up to 40 mol%). Cholesterol slightly diminished transfer activity at a liposome cholesterol/phospholipid molar ratio of 0.81. Similar effects were noted for the transfer to phospholipidcholine from microsomes to these various liposomes. Compared to standard liposomes, the magnitude of Km tended to increase for liposomes which depressed phospholipid transfer and to decrease for those which stimulated; little change was observed in the values of V. Single phospholipid liposomes of phosphatidylinositol were inhibitory when added to standard liposomes. Because bovine brain phospholipid exchange protein is able to distinguish among a wide spectrum of membrane interfaces, taking into account variations in the polar head groups as well as the fatty acyl moieties of the liposomal phospholipids, it may be considered a reasonable model system for protein-lipid and protein-membrane interactions.
Topics: Animals; Brain Chemistry; Carrier Proteins; Cattle; Kinetics; Liposomes; Nerve Tissue Proteins; Phosphatidic Acids; Phosphatidylcholines; Phosphatidylethanolamines; Phosphatidylinositols; Phosphatidylserines; Phospholipids; Sphingomyelins
PubMed: 7352996
DOI: 10.1016/0005-2736(80)90085-1 -
Biochimica Et Biophysica Acta Jul 1993Recent fast atom bombardment-mass spectrometry (FABMS) studies (Tsujimoto, K., Yorimitsu, S., Takahashi, T. and Ohashi, M. (1989) J. Chem. Commun. 668-670; Frederickson,...
Recent fast atom bombardment-mass spectrometry (FABMS) studies (Tsujimoto, K., Yorimitsu, S., Takahashi, T. and Ohashi, M. (1989) J. Chem. Commun. 668-670; Frederickson, H.L., De Leeuw, J.W., Tas, A.C., Van der Greef, J., LaVos, G.F. and Boon, J.J. (1989) Biomed. Environ. Mass. Spectrom. 18, 96-105; Kloppel, K.D. and Fredrickson, H.L. (1991) J. Chromatogr. 562, 369-376) have indicated that the structure of the major phospholipid of Halobacterium salinarium (formerly Halobacterium cutirubrum) is not 2,3-diphytanyl-sn-glycerol-1-phospho-3'-sn-glycerol-1'- phosphate (PGP), but the monomethylated derivative, 2,3-diphytanyl-sn-glycerol-1-phospho-3'-sn-glycerol-1'-methylphosphate (PGP-Me). We have now confirmed the structure of the major phospholipid of extremely halophilic archaebacteria as being this methylated structure (PGP-Me) by 1H- and 13C-NMR, FABMS and TLC of the native phospholipid and its product of mild acid hydrolysis PGP. The methylated structure (PGP-Me), rather than PGP itself, is also the major phospholipid in species of other genera of extreme halophiles examined so far, such as, Haloferax, Haloarcula, Halococcus, Natronobacterium and Natronococcus.
Topics: Chromatography, Thin Layer; Halobacterium; Magnetic Resonance Spectroscopy; Mass Spectrometry; Molecular Structure; Phosphatidylglycerols; Phospholipids
PubMed: 8334149
DOI: 10.1016/0005-2760(93)90080-s -
PloS One 2015The purpose of this work was to investigate the synthetic phospholipid dependence of permeability measured by parallel artificial membrane permeability assay (PAMPA)...
The purpose of this work was to investigate the synthetic phospholipid dependence of permeability measured by parallel artificial membrane permeability assay (PAMPA) method. Three phospholipids with hydrophobic groups of different lengths and phosphorylcholine as the hydrophilic group were concisely synthesized. Ten model drug molecules were selected because of their distinct human fraction absorbed (%FA) values and various pKa characteristics. In vitro drug permeation experiments were designed to determine the effect of the incubation time (4-20 h), pH gradient (4.6-9.32) and carbon chain length (8, 10, 12) on the drug permeability through the synthetic phospholipid membrane in the PAMPA system. The results showed that intensive and significant synthetic phospholipids dependence of permeability influenced by the length of lipid's hydrophobic carbon chain. The effective permeability constant (Pe) of each drug increased rapidly with time, then decreased slightly after reaching the maximum; the pH gradient changed the drug permeability according to the pH-partition hypothesis for drugs with diverse pKa values; and longer hydrophobic chains in the synthetic phospholipid membrane improved the drug permeability, as observed for all test drugs at almost all incubation time points. This newly proposed PAMPA model considered the synthetic phospholipid membrane and showed good Pe-%FA correlation for the passive transport of drugs, making it a helpful supplementary method for PAMPA systems.
Topics: Drug Stability; Humans; Hydrogen-Ion Concentration; Intestinal Absorption; Membranes, Artificial; Permeability; Phospholipids
PubMed: 25647086
DOI: 10.1371/journal.pone.0116502 -
Canadian Journal of Microbiology Jan 2001Species of Peptostreptococcus cause a variety of infections, primarily abscesses of soft tissues, joints, and mucous membranes. The aim of this study was to compare the... (Comparative Study)
Comparative Study
Species of Peptostreptococcus cause a variety of infections, primarily abscesses of soft tissues, joints, and mucous membranes. The aim of this study was to compare the phospholipid analogue profiles of Peptostreptococcus species, represented by P. anaerobius, P. asaccharolyticus, P. indolicus, P. lacrimalis, and P. prevotii; Micromonas micros (P. micros) and Finegoldia magna (P. magnus). After anaerobic growth on blood-FAA, lipids extracted by chloroform-methanol (2:1 v/v) were purified, then analysed by fast atom bombardment mass spectrometry (FAB-MS) in negative ion mode. The major peaks with mass to charge (m/z) 719, 721, and 749, corresponded to phosphatidylglycerol analogues, namely PG (32:1), PG (32:0), and PG (34:0), which have been found previously in Lactobacillus spp., Clostridium difficile, and Staphylococcus spp. Other major peaks observed, with m/z 619, 647, 665, 675, 677, 687, 691, 693, 701, 703, 707, 733, and 746 have also been reported in one or more of these three species. However, other major peaks found here in Peptostreptococcus, Micromonas, and Finegoldia have not been described elsewhere; these are 501, 514, 515, 618, 659, 673, 676, 688, 690, 692, 694, 700, 706, 715, 718, 722, and 750. We conclude that Peptostreptococcus, Micromonas, and Finegoldia isolates are chemically unique.
Topics: Anions; Peptostreptococcus; Phosphatidylglycerols; Phospholipids; Spectrometry, Mass, Fast Atom Bombardment
PubMed: 15049457
DOI: No ID Found -
Gynakologische Rundschau 1974
Topics: Amniotic Fluid; Dexamethasone; Female; Humans; Hyaline Membrane Disease; Infant, Newborn; Phospholipids; Pregnancy; Pulmonary Alveoli
PubMed: 4479956
DOI: No ID Found -
Investigative Ophthalmology & Visual... Dec 1994The major component of human lens membranes was thought to be sphingomyelin until 1991, when a study by phosphorus-31 (31P) nuclear magnetic resonance (NMR) spectroscopy...
PURPOSE
The major component of human lens membranes was thought to be sphingomyelin until 1991, when a study by phosphorus-31 (31P) nuclear magnetic resonance (NMR) spectroscopy revealed the presence of an unknown phospholipid that constituted approximately half the human lens phospholipids. The objective of this work was to isolate this phospholipid and to elucidate its identity.
METHODS
The separation of sphingomyelin from the unknown was accomplished using high-performance liquid chromatography (HPLC) and an amino-bound column. Sphingomyelin standard and the membranes from human lenses were chromatographed. Chromatographic fractions were collected and spectrally characterized by proton (1H) NMR and 31P NMR spectroscopy.
RESULTS
The chromatographic method did not affect the integrity of the sphingomyelin. Besides the bands corresponding to the unknown components, the chromatogram of the human lens membranes showed three large peaks, the central one with a shoulder, with elution times similar to that for sphingomyelin. The 1H NMR spectra for the fractions collected during the elution of these peaks showed differences. The study by 31P NMR indicated that the first peak contained the unknown phospholipid. The subsequent fractions showed the presence, in different relative levels, of both the unknown and sphingomyelin. By comparison and interpretation of the two-dimensional 1H NMR spectra for sphingomyelin and for the fraction containing the unknown, the unknown phospholipid is proposed to be 4,5 dihydrosphingomyelin, in which the site of unsaturation present in the sphingosine moiety is no longer present.
CONCLUSIONS
The ability to separate the unknown from sphingomyelin and the power of 1H NMR spectroscopy allowed the proposition of the identity of the major component of human lens membranes as 4,5-dihydrosphingomyelin. Although the synthetic compound is known to be involved in the formation of extended hydrogen-bonding networks, its biologic and physicochemical properties need further study.
Topics: Cell Membrane; Chromatography, High Pressure Liquid; Chromatography, Thin Layer; Humans; Lens, Crystalline; Magnetic Resonance Spectroscopy; Phospholipids; Sphingomyelins
PubMed: 8002253
DOI: No ID Found -
Journal of Lipid Research Apr 2001Electrospray ionization-mass spectrometry (ESI-MS) is a very promising tool for the analysis of phospholipid compositions, but is hampered by the fact that not all...
Electrospray ionization-mass spectrometry (ESI-MS) is a very promising tool for the analysis of phospholipid compositions, but is hampered by the fact that not all molecular species are detected with equal efficiency. We studied this and other issues that need to be taken into account to obtain truly quantitative compositional data. The key findings were as follows: First, the instrument response for both saturated and unsaturated phospholipid species decreased with increasing acyl chain length. This effect became increasingly prominent with increasing overall lipid concentration. Second, the degree of acyl chain unsaturation also had a significant effect on instrument response. At the highest concentration studied (10 pmol/microl), polyunsaturated species gave 40% higher intensity than the fully saturated ones. The effect of unsaturation diminished and nearly disappeared with progressive dilution. Third, the instrument response for the different head group classes varied markedly depending on the infusion solvent used. Notably, inclusion of ammonia in the infusion solvent eliminated sodium adduct formation in the positive ion mode, thus greatly simplifying the interpretation of the spectra. The fact that instrument response is dependent on many structural features, overall lipid concentration, solvent composition, and instrument settings makes it necessary to include several internal standards for each phospholipid class to obtain accurate data. Preferably, both unsaturated and saturated standards should be used. Finally, we quantified the major phospholipid classes of BHK cells using ESI-MS. The data agreed closely with those obtained with thin-layer chromatography and phosphorus analysis. This study indicates that quantitative compositional data can be obtained with ESI-MS, provided that proper attention is paid to experimental details, particularly the choice of internal standards.
Topics: Animals; Cell Line; Phospholipids; Reference Standards; Solvents; Spectrometry, Mass, Electrospray Ionization
PubMed: 11290839
DOI: No ID Found -
Journal of Chromatography Jun 1991A high-performance liquid chromatographic method for the quantification of major phospholipid classes is described. The separation was performed on Ultrasphere SI silica...
A high-performance liquid chromatographic method for the quantification of major phospholipid classes is described. The separation was performed on Ultrasphere SI silica gel columns with a mobile phase of acetonitrile-methanol-85% phosphoric acid (100:10:1.8. v/v) using isocratic elution and UV detection at 203 nm. Complete separation of phosphatidylserine, phosphatidylethanolamine, plasmalogen, phosphatidylcholine and sphingomyelin was achieved within 8 min. The plasmalogen was resolved from phosphatidylethanolamine in hydrochloric acid-derivatized samples, or without derivatization using a mobile phase composition of 100:40:0.4. The phospholipids were quantified by peak-area integration by means of the calibration. The detection limit is 5 ng. Human erythrocyte ghost membranes, lymphocytes and thrombocytes were analysed for these phospholipids. This method is suitable for routine clinical studies of membrane disorders in health, toxicity and disease, as well as in research.
Topics: Chromatography, High Pressure Liquid; Erythrocyte Membrane; Humans; Phosphatidylcholines; Phosphatidylethanolamines; Phosphatidylserines; Phospholipids; Plasmalogens; Spectrophotometry, Ultraviolet; Sphingomyelins
PubMed: 1918258
DOI: 10.1016/0378-4347(91)80306-w -
Clinica Chimica Acta; International... Aug 1980A fluorometric assay of phospholipid in serum is presented. The reaction is based upon the binding of phospholipids with a fluorescent probe: 1-6-Diphenyl-1-3-5...
A fluorometric assay of phospholipid in serum is presented. The reaction is based upon the binding of phospholipids with a fluorescent probe: 1-6-Diphenyl-1-3-5 hexatriene (DPH). The method is in very good agreement with other techniques for phospholipid estimation: phosphorus assay phospholipid extraction (Fiske and Subarrow), and enzymatic assay of phospholipid containing choline (Takayama). The correlation coefficient obtained was 0.81, when the proposed method was compared with the two other ones. Parameters influencing the reaction: DPH concentration, time and temperature of incubation are described. The normal range for human serum lies between 2.1 and 3.4 mmol/l. The sensitivity of the fluorometric assay is also sufficient for the determination of phospholipid in amniotic fluid and broncho-alveolar washings.
Topics: Amniotic Fluid; Bronchi; Fluorometry; Humans; Phospholipids; Phosphorus
PubMed: 7398090
DOI: 10.1016/0009-8981(80)90459-3