Structure of Lipid Tubules Formed from a Polymerizable Lecithin
Abstract
We have studied tubules formed a polymerizable lipid in aqueous dispersion using freeze-fracture replication and transmission electron microscopy. The polymerizable diacetylenic lecithin 1, 2-bis(10.12- tricosadiynoyl)-sn-glycero-3-phosphocholine converts from liposomes to hollow cylinders, which we call tubules, on cooling through its chain melting phase transition temperature. These tubules differ substantially from cochleate cylinders formed by phosphatidylserines on binding of calcium. The tubules have diameters that range from 0.3 to 1 micro and lengths of up to hundreds of micrometers depending on conditions of formation. The thickness of the walls varies from as few as two bilayers to tens of bilayers in some longer tubules. Their surfaces may be either smooth, gently rippled, or with spiral steps depending on sample preparation conditions, including whether the lipids have been polymerized. The spiral steps may reflect the growth of the tubules by rolling up of flattened liposomes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1985
- Accession Number
- ADA228253
Entities
People
- Alok Singh
- Carol Davies
- Paul E. Schoen
- Paul Yager
- Ronald Price
Organizations
- United States Naval Research Laboratory