Depth-Dependent Segmental Melting of the Sphingomyelin Alkyl Chain in Lipid Bilayers. 2022

Hiroshi Tsuchikawa, and Mami Monji, and Yuichi Umegawa, and Tomokazu Yasuda, and J Peter Slotte, and Michio Murata
Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560- 0043, Japan.

The chain melting of lipid bilayers has often been investigated in detail using calorimetric methods, such as differential scanning calorimetry (DSC), and the resultant main transition temperature is regarded as one of the most important parameters in model membrane experiments. However, it is not always clear whether the hydrocarbon chains of lipids are gradually melting along the depth of the lipid bilayer or whether they all melt concurrently in a very narrow temperature range, as implied by DSC. In this study, we focused on stearoyl-d-sphingomyelin (SSM) as an example of raft-forming lipids. We synthesized deuterium-labeled SSMs at the 4', 10', and 16' positions, and their depth-dependent melting was measured using solid-state deuterium NMR by changing the temperature by 1.0 °C, and comparing with that observed from a saturated lipid, palmitoylstearoylphosphatidylcholine (PSPC). The results showed that SSM exhibited a characteristic depth-dependent melting, which was not observed for PSPC. The strong intermolecular hydrogen bonds between the sphingomyelin amide moiety probably caused the chain melting to start from the chain terminus through the middle part and end in the upper part. This depth-dependent melting implies that the small gel-like domains of SSM remain at temperatures slightly above the main transition temperature. These sphingomyelin features may be responsible for the biological properties of SM-based lipid rafts.

UI MeSH Term Description Entries
D008051 Lipid Bilayers Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes. Bilayers, Lipid,Bilayer, Lipid,Lipid Bilayer
D010713 Phosphatidylcholines Derivatives of PHOSPHATIDIC ACIDS in which the phosphoric acid is bound in ester linkage to a CHOLINE moiety. Choline Phosphoglycerides,Choline Glycerophospholipids,Phosphatidyl Choline,Phosphatidyl Cholines,Phosphatidylcholine,Choline, Phosphatidyl,Cholines, Phosphatidyl,Glycerophospholipids, Choline,Phosphoglycerides, Choline
D002152 Calorimetry, Differential Scanning Differential thermal analysis in which the sample compartment of the apparatus is a differential calorimeter, allowing an exact measure of the heat of transition independent of the specific heat, thermal conductivity, and other variables of the sample. Differential Thermal Analysis, Calorimetric,Calorimetric Differential Thermal Analysis,Differential Scanning Calorimetry,Scanning Calorimetry, Differential
D003903 Deuterium The stable isotope of hydrogen. It has one neutron and one proton in the nucleus. Deuterons,Hydrogen-2,Hydrogen 2
D013109 Sphingomyelins A class of sphingolipids found largely in the brain and other nervous tissue. They contain phosphocholine or phosphoethanolamine as their polar head group so therefore are the only sphingolipids classified as PHOSPHOLIPIDS. Sphingomyelin
D013696 Temperature The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms. Temperatures
D021962 Membrane Microdomains Detergent-insoluble CELL MEMBRANE components. They are enriched in SPHINGOLIPIDS and CHOLESTEROL and clustered with glycosyl-phosphatidylinositol (GPI)-anchored proteins. Lipid Rafts, Cell Membrane,Sphingolipid Microdomains,Sphingolipid-Cholesterol Rafts,Membrane Microdomain,Microdomain, Membrane,Microdomain, Sphingolipid,Microdomains, Membrane,Microdomains, Sphingolipid,Sphingolipid Cholesterol Rafts,Sphingolipid Microdomain,Sphingolipid-Cholesterol Raft

Related Publications

Hiroshi Tsuchikawa, and Mami Monji, and Yuichi Umegawa, and Tomokazu Yasuda, and J Peter Slotte, and Michio Murata
March 2001, Chemistry and physics of lipids,
Hiroshi Tsuchikawa, and Mami Monji, and Yuichi Umegawa, and Tomokazu Yasuda, and J Peter Slotte, and Michio Murata
January 2007, Molecular membrane biology,
Hiroshi Tsuchikawa, and Mami Monji, and Yuichi Umegawa, and Tomokazu Yasuda, and J Peter Slotte, and Michio Murata
March 2024, The Journal of chemical physics,
Hiroshi Tsuchikawa, and Mami Monji, and Yuichi Umegawa, and Tomokazu Yasuda, and J Peter Slotte, and Michio Murata
May 2024, Biophysical chemistry,
Hiroshi Tsuchikawa, and Mami Monji, and Yuichi Umegawa, and Tomokazu Yasuda, and J Peter Slotte, and Michio Murata
October 1985, Biochemistry,
Hiroshi Tsuchikawa, and Mami Monji, and Yuichi Umegawa, and Tomokazu Yasuda, and J Peter Slotte, and Michio Murata
February 2022, Biochimica et biophysica acta. Biomembranes,
Hiroshi Tsuchikawa, and Mami Monji, and Yuichi Umegawa, and Tomokazu Yasuda, and J Peter Slotte, and Michio Murata
February 2006, Biophysical journal,
Hiroshi Tsuchikawa, and Mami Monji, and Yuichi Umegawa, and Tomokazu Yasuda, and J Peter Slotte, and Michio Murata
November 1986, Biochemistry,
Hiroshi Tsuchikawa, and Mami Monji, and Yuichi Umegawa, and Tomokazu Yasuda, and J Peter Slotte, and Michio Murata
January 1986, Methods in enzymology,
Hiroshi Tsuchikawa, and Mami Monji, and Yuichi Umegawa, and Tomokazu Yasuda, and J Peter Slotte, and Michio Murata
April 2013, Biochimica et biophysica acta,
Copied contents to your clipboard!