Amino acid sequence for the peptide extension on the prolipoprotein of the Escherichia coli outer membrane.

Abstract

The messenger RNA for the lipoprotein of the E. coli outer membrane was found to code for a putative precursor, prolipoprotein, which has 20 additional amino acid residues extending from the amino terminus of the lipoprotein. Using the prolipoprotein synthesized in an E. coli cell-free system directed by purified messenger RNA for the lipoprotein, the complete amino acid sequence of the amino-terminal precursor region was determined to be as follows: (formula: see text). It was also found that the prolipoprotein that accumulates in toluene-treated cells has the same sequence. The significance of the amino acid sequence is discussed in terms of the mechanism of biosynthesis and assembly of the lipoprotein in the E. coli outer membrane.