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Spherosome membranes: half unit-membranes
Plant Physiology
|June 1, 1972
Summary
Spherosomes have unique single-line membranes, unlike typical unit-membranes. These structures are interpreted as half unit-membranes, confirmed by biochemical and immunological analysis of membrane proteins.
Area of Science:
- Plant Cell Biology
- Biochemistry
- Membrane Biology
Background:
- Spherosomes are plant organelles with unusual bounding membranes.
- Standard biological membranes are tripartite unit-membranes (6-8.5 nm thick).
- Spherosome membranes are distinct, measuring 2-3.5 nm in width.
Purpose of the Study:
- To characterize the structure and composition of spherosome membranes.
- To determine if spherosome membranes are true biological membranes.
- To compare spherosome membrane proteins with known membrane proteins.
Main Methods:
- Morphological analysis of spherosome membrane structure.
- Biochemical assays to detect membrane structural proteins in spherosomes.
- Immunological comparison of spherosome membrane proteins with mitochondrial proteins.
Main Results:
- Spherosome membranes are morphologically interpreted as half unit-membranes.
- Membrane structural protein was identified in peanut spherosomes.
- Immunological identity was found between spherosome and seedling mitochondrial membrane proteins.
Conclusions:
- Spherosome membranes are atypical biological membranes.
- These membranes function as half unit-membranes.
- Spherosome membranes share antigenic properties with mitochondrial membranes.
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