Disease relevance of lpp

• Insertion of the modified gene into a runaway-replication plasmid under the control of a fused lpp promoter and lac promoter/operator, resulted in the overexpression by Escherichia coli of the modified PBP3 (designated PBP3**) in the cytoplasm [1].
• Here we demonstrate that two transcripts, which were shown previously to be substrates for poly(A) polymerase I (PAP I), Escherichia coli lpp messenger RNA and bacteriophage lambda oop RNA, are polyadenylated more efficiently in slowly growing bacteria than in rapidly growing bacteria [2].
• In addition, our results demonstrate the general utility of fusions to lpp-ompA for the efficient display of proteins and the engineering of the surface topology of Gram-negative bacteria [3].
• A 1.1-kilobase (kb) EcoRI DNA segment from an isolate of HTLV-III was inserted into a lpp and lac promoter-coupled expression vector, pIN-III-ompA [4].
• A DNA sequence of 532 base pairs encompassing the entire Morganella morganii lipoprotein gene (lpp) was determined [5].

High impact information on lpp

• We have constructed a plasmid that produces a complementary RNA to the E. coli lpp mRNA (mic[Ipp] RNA) [6].
• (d) The nucleotide sequence from position 46 to 168 of the lpp gene was deleted [7].
• However, the 3' end position of the lpp gene of 154 bp was retained, which contains not only translation termination codons in three different reading frames but also the transcription termination signal of the lpp gene [7].
• When the cell envelope of MM18 containing unmodified prolipoprotein was incubated in the presence of detergent with [2-3H]glycerol-labeled cell envelope of strain JE5505 lacking murein lipoprotein, incorporation of [2-3H]glycerol radioactivity into both prolipoprotein and processed mature lipoprotein was observed [8].
• These data provide the first direct evidence that the TNF inducing lipid modification of native Borrelia lipoproteins is a structural homologue of the murein lipoprotein of Escherichia coli [9].

Chemical compound and disease context of lpp

• Poly(A) RNA in Escherichia coli: nucleotide sequence at the junction of the lpp transcript and the polyadenylate moiety [10].
• In addition to the prolipoprotein, two ery-lpp hybrid proteins containing a 45- and a 22-amino acid extension preceding the NH2 terminus of prolipoprotein, respectively, are also synthesized in E. coli [11].
• When a lipoprotein-deficient (lpp) mutant of Escherichia coli was transformed with pBR322 carrying the S. marcescens lpp gene, cells became nonleaky for ribonuclease, resistant to ethylenediaminetetraacetic acid, and sensitive to globomycin [12].
• Lipoprotein was briefly induced with isopropyl-beta-D-thiogalactopyranoside in cells carrying lac-lpp on a low-copy-number plasmid in an E. coli lpp host [13].
• In the absence of the chaperone or the usher, FaeC could not be detected in E. coli cells harbouring the faeC gene and its ribosome binding site under contol of the IPTG inducible lpp/lac promoter/operator [14].

Biological context of lpp

• An RNA chaperon, Hfq, and polyadenylation at 3' ends of mRNA are known key factors for destabilization of ompA and lpp mRNAs in uninfected cells [15].
• To explore chitin-binding domain (ChBD)-based cell immobilization, a tripartite gene fusion consisting of an in-frame fusion of ChBD to lpp and ompA was constructed and expressed in Escherichia coli [16].
• By comparing the restriction maps of the cloned fragment and the E. coli chromosome, the purR gene was found to be located very close to the lpp gene (36.3 min) [17].
• The pIP111 vector is a promoterless derivative of pCH110 (SV40 early region promoter-lacZ) and contains the Escherichia coli lpp transcription terminator sequence at the 5' end of the cloning site [18].
• The chemically synthesized gene was inserted downstream from the ompA signal peptide of the E. coli expression vector, pIN-III-ompA, which carries lpp and lac promotors [19].

Anatomical context of lpp

• Together with the previously reported observation that overproduced TolA complements an lpp but not a pal strain, these results indicate that the cell envelope integrity is efficiently stabilized by an epistatic Tol-Pal system linking inner and outer membranes [20].
• A fragment of human DNA encoding the mature form of interferon alpha 2 (hIFN-alpha 2), and carrying both an in-phase ATG initiation codon and the ribosome binding site (RBS) of the Escherichia coli membrane lipoprotein gene (lpp), was fused to the aminoglycoside phosphotransferase gene (aph) promoter (aphP) from Streptomyces fradiae [21].
• Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of proteins synthesized in spheroplasts revealed the preferential synthesis of five polypeptides, one of which has been identified as the free form of murein lipoprotein [22].
• Murein lipoprotein from the outer membrane of Escherichia coli could be fixed to erythrocytes without pretreatment of the erythrocytes [23].

Associations of lpp with chemical compounds

• These pseudorevertants in the lpp gene which could be recognized by the anomalous prolipoprotein mobility in sodium dodecyl sulfate gels, exhibited altered globomycin sensitivity in vivo [24].
• DNA sequence analysis of the mutant lpp allele and determination of the amino acid composition of the mutant lipoprotein revealed a single amino acid substitution of cysteine for arginine at the 68th amino acid residue of prolipoprotein [25].
• Whereas small amphipaths (chlorpromazine, trinitrophenol) or a larger amphipath (lysolecithin) all activated the MS channel in the wild-type membrane under minimal suction, only the larger lysolecithin could activate the MS channel in the lpp membranes [26].
• Radioactive labeling experiments in the presence or absence of globomycin showed that the hybrid protein is modified with a diglyceride and fatty acids and is processed by signal peptidase II, as is the murein lipoprotein [27].
• Mutants with alterations in the structure, biosynthesis, or assembly of murein lipoprotein were selected by a procedure based on radiation suicide of wild-type organisms by [3H]arginine under conditions where the radioactive arginine was preferentially incorporated into lipoprotein [28].

Regulatory relationships of lpp

• The modified ftsI genes were placed under the control of the fused lpp promoter and lac promoter/operator; expression of the truncated PBP3s was optimized by varying the copy number of the recombinant plasmids and the amount of LacI repressor, and export was facilitated by increasing the SecB content of the producing strain [29].

Other interactions of lpp

• Stable E. coli mRNAs such as lpp and ompA were drastically destabilized immediately after infection [15].
• Surprisingly, the expression of ompF under the lpp promoter was still osmoregulated not only in the ompB+ strain but also in two ompB strains tested [30].
• In addition, we show that the expression of ompF under the lpp promoter has no direct effect on ompC expression [30].
• In this study, the roles of Pal and major lipoprotein Lpp were compared in Escherichia coli. lpp and tol-pal mutations have previously been found to perturb the outer membrane permeability barrier and to cause the release of periplasmic proteins and the formation of outer membrane vesicles [20].
• Other outer membrane defective strains such as tolC, lpp, and rfa mutations are also altered in their outer membrane permeability [31].

Analytical, diagnostic and therapeutic context of lpp

• Mutations in the Escherichia coli lpp gene resulting in the alterations of the COOH-terminal region of the lipoprotein have been isolated by oligonucleotide-directed mutagenesis [32].
• Furthermore, real-time PCR analysis indicates that the extent of polyadenylation of individual full-length transcripts such as lpp and ompA varies significantly in wild-type cells [33].
• For the in vivo lipidation strategy, a general expression vector was constructed encoding a composite tag consisting of a sequence (lpp) of the major lipoprotein of E. coli, fused to a dual affinity fusion tag to allow efficient recovery by affinity chromatography [34].
• To identify protein contaminants of LPSs, we performed immunoblotting using, as antigen, purified LPS from various species of bacteria and, as primary antibodies, anti-murein lipoprotein (MLP), peptidoglycan-associated lipoprotein (PAL), and outer membrane protein A (OmpA) [35].
• Our goal in the current work was to determine if passive immunization directed to MLP and PAL protects mice from Gram-negative sepsis [36].

References