Phospholipases and acyltransferases in macrophages.

In contrast to many other cells, macrophages contain a phospholipase A2, which preferentially liberates arachidonic acid from the main phospholipids. In unstimulated macrophages this acylchain-specific phospholipase A2 is localized in the lipid-free cytosol and thus without function. After activation of protein kinase C with diacylglycerols, the cytosolic phospholipase A2 is translocated to cellular membranes.

Translocation of phospholipase A2 from cytosol to membranes induced by 1-oleoyl-2-acetyl-glycerol in serum-free cultured macrophages.

Macrophages exhibit high activities of a phospholipase A2 which preferentially cleaves arachidonic acid (I. Flesch, B. Schmidt, and E.

Fusion of liposomes and chromatophores of Rhodopseudomonas capsulata: effect on photosynthetic energy transfer between B875 and reaction center complexes.

The photosynthetic chromatophore membranes of Rhodopseudomonas capsulata were fused with liposomes to investigate the effects of lipid dilution on energy transfer between the bacteriochlorophyll-protein complexes of this membrane. Phosphatidylcholine-containing liposomes were mixed with chromatophores at pH 6.0 to 6.