ABSTRACT
The purified messenger ribonucleic acid (mRNA) for the lipoprotein of the Escherichia coli outer membrane was hybridized with fragments obtained by digestion of E. coli chromosomal deoxyribonucleic acid (DNA) with eight different restriction enzymes. For each restriction enzyme digestion, one specific fragment separated by agarose gel electrophoresis was found to hybridize with the lipoprotein mRNA. From the analysis of restriction fragments generated by double digestions with various combinations of restriction enzymes, cleavage sites for the restriction enzymes near the locus of the lipoprotein structural gene (lpp) were mapped. No restriction fragments of DNA from the E. coli lpp-2 mutant hybridized with the lipoprotein mRNA, confirming that the mutant has a deletion mutation in the vicinity of the lpp gene.
