A gene for a new lipoprotein in the dapA-purC interval of the Escherichia coli chromosome.
Cloning and sequence analysis of the region located downstream of the dapA gene of Escherichia coli has revealed the presence of an open reading frame that is cotranscribed with dapA. This gene codes for a 344-amino-acid polypeptide with a potential signal sequence characteristic of a lipoprotein. When this gene, called nlpB, is expressed from a multicopy plasmid in bacteria grown in the presence of [3H]palmitate, a labeled 37-kDa protein is produced. A slightly larger precursor molecule is detected when minicells expressing nlpB are treated with globomycin, a specific inhibitor of lipoprotein signal peptidase. Therefore, the nlpB gene encodes a new lipoprotein, designated NlpB. This lipoprotein is detected in outer membrane vesicles prepared from osmotically lysed spheroplasts and appears to be nonessential, since a strain in which the nlpB gene is disrupted by insertion of a chloramphenicol resistance gene is still able to grow and shows no discernible NlpB phenotype. The putative transcription termination signals of the dapA-nlpB operon overlap the promoter of the adjacent purC gene.
Bouvier
J
J
Institut de Microbiologie, Bâtiment 409, Université Paris-Sud, France.
Pugsley
A P
AP
Stragier
P
P
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial; D004269:DNA, Bacterial; D004274:DNA, Recombinant / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics*; D005798:Genes, Bacterial; D008074:Lipoproteins / Q000235:genetics*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D021382:Protein Sorting Signals / Q000235:genetics; D015183:Restriction Mapping; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004274:DNA, Recombinant; D008074:Lipoproteins; D021382:Protein Sorting Signals