Phospholipids showing complex bilayer phase transitions. II. Four sulfur-containing phosphatidylcholines.

ABSTRACT: The main phase transitions of aqueous dispersions of four synthetic phosphatidylcholines (PCs) containing sulfur atoms in thioester and thioether linkages have been studied by high sensitivity differential scanning calorimetry (DSC). The transition enthalpies ranged from 7.4 to 10.3 kcal mol-1, with values for tm, the temperature of maximal excess heat capacity, in the range 38.0 to 40.8 degrees C. The corresponding values for dipalmitoyl PC (DPPC) are 8.5 kcal mol-1 and 41.7 degrees C. Curve fitting required the sum of from one to four two-state components to give an accurate representation of the observed DSC curves. Comparison of the results given here with those reported by B.Z. Chowdhry, G. Lipka, J. Hajdu and J.M. Sturtevant, (1984) Biochemistry 23, 2044-2049, for PCs containing amid

SUBMITTER: Hajdu J 

PROVIDER: S-EPMC3560930 | biostudies-literature | 1990 Sep

REPOSITORIES: biostudies-literature