Related Experiment Video
Updated: Jun 28, 2026
10:46
A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data
Published on: December 9, 2015
Vitamin D(2) modulates melittin-membrane interactions
F Severcan1, H Okan Durmus, F Eker
1Department of Biology, Middle East Technical University, 06531 Ankara, Turkey.
Talanta
|October 31, 2008
Summary
Vitamin D(2) reduces the membrane-disrupting effects of melittin, a bee venom toxin, on phospholipid liposomes. This antioxidant steroid helps stabilize the lipid bilayer, promoting a more ordered membrane structure.
Area of Science:
- Biochemistry
- Biophysics
- Membrane Biology
Background:
- Melittin, a pore-forming toxin from bee venom, significantly destabilizes phospholipid membranes.
- Vitamin D(2) is an antioxidant steroid with potential membrane-modulating properties.
Purpose of the Study:
- To investigate the interaction between melittin, vitamin D(2), and dipalmitoyl phosphatidylcholine (DPPC) multilamellar liposomes.
- To determine how vitamin D(2) modulates the effects of melittin on DPPC membrane structure and stability.
Main Methods:
- Turbidity measurements
- Fourier transform infrared (FTIR) spectroscopy
- Thermodynamic calculations
Main Results:
- Melittin alone disorders DPPC membranes and lowers their phase transition temperature.
- Vitamin D(2) inclusion, particularly at higher concentrations, shifts the phase transition to lower temperatures and broadens the transition curve.
- Vitamin D(2) addition reduces melittin's membrane perturbing effects, leading to a more ordered lipid system.
Conclusions:
- Vitamin D(2) counteracts the destabilizing and disordering effects of melittin on DPPC liposomes.
- The antioxidant steroid vitamin D(2) enhances the stability and order of phospholipid membranes affected by melittin.
Related Concept Videos
01:16Calmodulin-dependent Signaling
Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
01:15Receptor Downregulation in MVBs
Multivesicular bodies (MVBs) are mature endosomes that sort ubiquitinated proteins and then fuse with lysosomes to degrade the sorted proteins. Epidermal growth factor (EGF) and its receptor (EGFR) form a complex that can be internalized through endocytosis, sorted into an MVB, and later degraded.
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...
01:23Role of Skin in Vitamin D Synthesis
The skin plays a crucial role in the synthesis of vitamin D, a vital nutrient for various physiological processes in the body. Vitamin D is unique because it can be synthesized in the skin through a series of chemical reactions triggered by exposure to ultraviolet B (UVB) radiation from sunlight.
The solar UV B rays (290-315 nm) are absorbed by the skin, and 7-dehydrocholesterol (provitamin D3) photolyzes it to previtamin D3, which undergoes a rapid transformation to vitamin D3(cholecalciferol).
The solar UV B rays (290-315 nm) are absorbed by the skin, and 7-dehydrocholesterol (provitamin D3) photolyzes it to previtamin D3, which undergoes a rapid transformation to vitamin D3(cholecalciferol).