Related Experiment Video
Updated: Aug 9, 2026
07:31
Realistic Membrane Modeling Using Complex Lipid Mixtures in Simulation Studies
Published on: September 1, 2023
Characterization of two oxidatively modified phospholipids in mixed monolayers with DPPC
Karen Sabatini1, Juha-Pekka Mattila, Francesco M Megli
1Dipartimento di Biochimica e Biologia Molecolare, Università di Bari, Centro di Studio sui Mitocondri e Metabolismo Energetico--CNR, Bari, Italy.
Biophysical Journal
|April 4, 2006
Summary
Oxidatively modified phospholipids alter membrane structure and organization. These changes, observed in mixed monolayers, suggest impacts on membrane-associated proteins and cellular functions.
Area of Science:
- Biochemistry
- Membrane Biophysics
- Lipid Chemistry
Background:
- Oxidative modification of phospholipids is a key factor in cellular damage.
- Understanding how oxidized lipids affect membrane properties is crucial for cell biology.
Purpose of the Study:
- To investigate the biophysical properties of two specific oxidized phospholipids (PoxnoPC and PazePC).
- To determine the impact of these oxidized phospholipids on model membrane monolayers, particularly when mixed with DPPC.
Main Methods:
- Langmuir balance technique to record force-area (pi-A) isotherms and surface potential (psi).
- Fluorescence microscopy to visualize monolayer organization.
- Analysis of mixed monolayers composed of oxidized and non-oxidized phospholipids.
Main Results:
- Oxidized phospholipids disrupted the liquid expanded-liquid condensed transition in DPPC monolayers.
- A critical pressure (approx. 42 mN/m) was identified where oxidized phospholipids reoriented and solubilized into the aqueous phase.
- Surface potential changes indicated the loss of oxidized phospholipids from the monolayer at this critical pressure.
Conclusions:
- Lipid oxidation significantly alters both the micro- and macro-scale organization of biological membranes.
- Oxidized phospholipids can influence the structure and function of membrane-associated proteins.
- These findings provide insights into the role of lipid oxidation in membrane dynamics and cellular processes.
More Related Videos
Related Concept Videos
01:35Asymmetric Lipid Bilayer
Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric membranes. The treatment of the erythrocyte membrane with the enzyme phospholipase confirmed the asymmetric nature of the lipid bilayer. The enzyme hydrolyzes lipids into fatty acids and hydrophilic groups. The phospholipase acts only on the outer layer of the membrane, while the inner layer remains intact. The phospholipase treatment resulted in 80%...
01:28Overview of Fatty Acid Metabolism
Lipids also are sources of energy that power cellular processes. Like carbohydrates, lipids are composed of carbon, hydrogen, and oxygen, but these atoms are arranged differently. Most lipids are nonpolar and hydrophobic. Major types include fats and oils, waxes, phospholipids, and steroids.
Fatty acids are catabolized in a process called beta-oxidation, which takes place in the matrix of the mitochondria and converts their fatty acid chains into two-carbon units of acetyl groups. The acetyl...
Fatty acids are catabolized in a process called beta-oxidation, which takes place in the matrix of the mitochondria and converts their fatty acid chains into two-carbon units of acetyl groups. The acetyl...
01:32Membrane Lipids
Lipids are an essential component of all biological membranes. The average lipid content in mammalian membranes is 50%, though it can be as low as 20% in the inner mitochondrial membrane or as high as 80% in the myelin sheath present around the nerve cells.
Phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin are the most common phospholipids present in mammalian membranes. At physiological pH, phosphatidylserine is negatively charged, while the other three...
Phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin are the most common phospholipids present in mammalian membranes. At physiological pH, phosphatidylserine is negatively charged, while the other three...
01:42Phosphoinositides and PIPs
Phosphoinositides are a group of phospholipids containing a glycerol backbone with two fatty acid chains and a phosphate attached to a myoinositol sugar ring. The inositol head group extends into the cytoplasm, where it is modified by adding phosphate groups to form phosphatidylinositol phosphates or PIPs.
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
01:38What are Lipids?
Overview
01:27Synthesis of Phosphatidylcholine in the ER Membrane
The ER synthesizes lipids for building cell membranes and performing cellular functions such as energy storage and signaling. The lipid synthesis machinery embedded in the ER membrane primarily collects all reactants from the cytosol. Following synthesis, the secretory pathway and the ER contact sites distribute these lipids to other cellular organelles. Additionally, the energy-rich triacylglycerides are transported from the ER via lipid droplets.
The major components of all eukaryotic cell...
The major components of all eukaryotic cell...