title: Structure and synthesis of a lipid-containing bacteriophage. Studies on the structure of the bacteriophage PM2 nucleocapsid.
abstract: The nucleocapsid of bacteriophage PM2, prepared according to Schäfer et al. [Eur. J. Biochem. 92, 579-588 (1978)], was studied by biochemical and biophysical methods. It was not possible to isolate the lipid-free nucleocapsid. More than 95% of the lipids were associated with the nucleocapsid. The asymmetric distribution of phospholipids across the viral membrane was retained in the nucleocapsid since less than 10% of the phosphatidylethanolamine was accessible to the non-penetrable membrane probe, 2,4,6-trinitrobenzenesulfonate. Micro-dissection of the nucleocapsid with thermolysin demonstrated the asymmetric orientation of core proteins across the nucleocapsid membrane. Protein III was embedded deeply in the lipid bilayer and about 20% of the molecule extended to the exterior. Protein IV interacts with PM2 DNA and is partially in the inner leaflet of the bilayer. Small-angle X-ray scattering studies on the nucleocapsid enabled us to localize the lipid bilayer structure at radii from 20.5 nm to 24.0 nm.
mesh_terms: D001435:Bacteriophages / Q000032:analysis / Q000648:ultrastructure*; D002213:Capsid / Q000032:analysis; D003852:Deoxyribonucleoproteins / Q000032:analysis; D008563:Membrane Lipids / Q000032:analysis; D008565:Membrane Proteins / Q000032:analysis; D010714:Phosphatidylethanolamines / Q000032:analysis; D010715:Phosphatidylglycerols / Q000032:analysis; D010743:Phospholipids / Q000032:analysis; D012542:Scattering, Radiation; D013820:Thermolysin / Q000378:metabolism; D014764:Viral Proteins / Q000032:analysis
chemical_list: D003852:Deoxyribonucleoproteins; D008563:Membrane Lipids; D008565:Membrane Proteins; D010714:Phosphatidylethanolamines; D010715:Phosphatidylglycerols; D010743:Phospholipids; D014764:Viral Proteins; D013820:Thermolysin