Lipid Dependent Mechanisms of Protein Pump Activity
Abstract
Despite the enormous progress which has been made in understanding the structure and function of biomembranes, there still is no satisfactory understanding of the factors which determine the polar lipid composition of cell membranes. In particular, the functional interactions between the lipids and intrinsic membrane proteins of cell membranes are unknown. this project is aimed at investigating if a lipid elastic property, known as the spontaneous radius of curvature RO, is a regulated membrane property and if its value modulates membrane protein activity. Specific aims reported on here include: 1) Correlation of ion pump/channel activity with Ro by reconstitution of membrane proteins in vesicles with different Ro values obtained by different lipid compositions; and 2) The development of new techniques for measuring Ro which are more suitable for native membranes. Toward these ends we have reconstituted the Ca ++ ATPase of sarcoplasmic reticulum into vesicles and detected a positive correlation of the pump coupling efficiency with Ro. Combined x-ray diffraction and NMR studies on deuterated lipids are underway to correlate the quadrupole splitting with the x-ray determined Ro value.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 23, 1989
- Accession Number
- ADA208900
Entities
People
- Sol M. Gruner
Organizations
- Princeton University