Abstract
Membrane-bound lipids of isolated guinea pig liver microsomal membranes were selectively enzymatically labelled with isomeric (5-, 12-, and 16-)doxyl stearic acid. After reisolation, the membranes were degraded with phospholipases D and C under conditions not requiring detergents or organic solvent activators. The degradation of membrane-bound lipids occurred according to the recognized specificity of phospholipases D and C. Temperature-induced changes of degraded membranes containing radioactive spin-labelled isomeric lipids were followed by the electron spin resonance and spectral changes correlated with the lipid composition of membranes. Discontinuities in plots of experimental spectral parameters versus temperature detected in the case of microsomal membranes before and after degradation with phospholipases D and C were attributed to lipid-protein and lipid-lipid interaction(s). On the basis of these and control experiments, discontinuity at around 10-12 degrees C was attributed to the microsomal membrane phosphatidylcholine intrinsic microsomal membrane protein interaction(s), while discontinuities detected at 19-21 degrees C approximately and at 20-30 degrees C approximately were attributed to the phase separation of Ca or Zn salts of membranous phosphatidic acid and to the similar phenomenon involving membrane-bound diglycerides respectively.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
