Accession Number : ADA264957


Title :   Probability of Alamethicin Conductance States Varies with Nonlamellar Tendency of Bilayer Phospholipids


Corporate Author : PRINCETON UNIV NJ DEPT OF PHYSICS


Personal Author(s) : Keller, S L ; Bezrukov, A M ; Gruner, S M ; Tate, M W ; Vodyanoy, I


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a264957.pdf


Report Date : Feb 1993


Pagination or Media Count : 24


Abstract : With few exceptions (1-3), membrane lipids are usually regarded as a kind of filler or passive solvent for membrane proteins. Yet, cells exquisitely control membrane composition. Many phospholipids found in plasma membrane bilayers favor packing into inverted hexagonal bulk phases (4-6). It was suggested that the strain of forcing such lipids into a bilayer may affect membrane protein function, such as the operation of trans-membrane channels (7- 10, 6). To investigate this, we have inserted the peptide alamethicin into bilayer membranes composed of lipids of empirically determined inverted hexagonal phase 'spontaneous radii' Ro, which will have expectably different degrees of strain when forced into bilayer form. We observe a correlation between measured Ro and the relative probabilities of different conductance states. States of higher conductance are more probable in Dioleoyl Phosphatidyl Ethanolamine (DOPE), the lipid of highest curvature, 1/Ro, than in Dioleoyl Phosphatidyl Choline (DOPC), the lipid of lowest curvature.


Descriptors :   *MEMBRANES(BIOLOGY) , *CELL WALL , *PHOSPHOLIPIDS , FUNCTIONS , CONDUCTIVITY , PEPTIDES , BIOCHEMISTRY , LIPIDS , PROTEINS , CHOLINES , CURVATURE , ETHANOLAMINE , CELL STRUCTURE , OPERATION , SOLVENTS , MEMBRANES , PHYSIOLOGY , CELLS(BIOLOGY) , CHANNELS , RECEPTOR SITES(PHYSIOLOGY)


Subject Categories : Biochemistry
      Anatomy and Physiology


Distribution Statement : APPROVED FOR PUBLIC RELEASE