The receptor of bacteriophage lambda: evidence for a biosynthesis dependent on lipid synthesis

Inhibition of lipid synthesis in cerulenin-treated cells or in a mutant strain defective in sn-glycerol-3-phosphate acyltransferase after glycerol deprivation, results in a marked decrease of insertion of lamB protein into the outer membrane. No lambda receptor was found in any other cell compartment or in the medium under these conditions. The LamB protein synthesis was inhibited by about 70% in the absence of lipid synthesis. The residual 30% protein produced during inhibition of fatty-acid or phospholipid synthesis, was probably incorporated into the outer membrane since no further incorporation was observed after resumption of these syntheses. Besides OmpF and OmpC protein [Bocquet-Pagès, C., Lazdunski, C., and Lazdunski, A. (1981) Eur. J. Biochem. 118, 105-111], at least four other proteins of the outer membrane are also subject to alteration of levels in the absence of lipid synthesis. Under these conditions the uptake of maltose, like the uptake of 5'AMP [Bocquet-Pagès, C., Lazdunski, C., and Lazdunski, A. (1981) Eur. J. Biochem. 118, 105-111], was inhibited as much as 60%. These results are discussed with regard to the biosynthesis and assembly of the outer membrane proteins.