Disease relevance of ompA

• Primary structure of major outer membrane protein II (ompA protein) of Escherichia coli K-12 [1].
• Here we report that the 78 nucleotide SraD RNA, which is highly conserved among Enterobacteriaceae, acts in destabilizing the ompA transcript when rapidly grown cells enter the stationary phase of growth [2].
• In addition, genes specific to E. coli were also studied: ompA, ompFand tolA (predicting epigenetic variation that could help escape infection by phages or colicins) [3].
• The ompA gene was fused to the gene (tet) specifying tetracycline resistance and the gene for the major antigen (vp1) of foot-and-mouth disease virus [4].
• 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 [5].

High impact information on ompA

• Highly purified RNAase E correctly processed E. coli 5S ribosomal RNA, bacteriophage T4 gene 32 mRNA and E. coli ompA mRNA at sites known to depend on the rne gene for cleavage in vivo [6].
• Thus the 5' noncoding region appears to be a determinant of mRNA stability, and endonucleolytic cleavages in the 5' noncoding region may well regulate expression of the ompA gene [7].
• The stabilities of two of these species, the transcripts of the ompA and cat genes, exhibited a marked dependence on cell growth rate, whereas the half lives of the transcripts of the lpp and bla genes are constant over a broad range of cell doubling times [8].
• Here, we present the first direct demonstration that 30S ribosomes bound to the ompA 5'-UTR protect the transcript from RNase E cleavage in vitro [9].
• Thus, the regulation of ompA mRNA stability meets the physiological needs to adjust the level of ompA expression to the rate of cell division [9].

Chemical compound and disease context of ompA

• Outer membrane of Escherichia coli K-12: differentiation of proteins 3A and 3B on acrylamide gels and further characterization of con (tolG) mutants [10].
• A group of ompA mutants of Escherichia coli K12 are described which were sensitive to bacteriophage K3 in a background wild-type for lipopolysaccharide (LPS) [11].
• To analyze the effect of cyclic AMP on the expression of the ompA gene of Escherichia coli, encoding the outer-membrane protein OmpA, a fusion between this gene and the lacZ gene was constructed in vitro by using a promoter-probe plasmid [12].
• Selection for toxicity of ompA expression following mutagenesis with sodium bisulfite yielded genes with multiple base pair substitutions, the majority of which resulted in amino acid substitutions in the membrane moiety of the protein [13].
• An E. coli K1 ompA-deletion mutant was significantly more sensitive than that of its parent strain to sodium dodecyl sulfate (SDS), cholate, acidic environment, high osmolarity, and pooled human serum [14].

Biological context of ompA

• The amino acid sequence of major outer membrane protein II (ompA protein) from Escherichia coli K-12 has been determined [1].
• Regulatory region of the gene for the ompA protein, a major outer membrane protein of Escherichia coli [15].
• Our results indicate that distinct regulatory circuits are responsible for growth phase- and growth rate-dependent control of the ompA mRNA stability [2].
• Nucleotide sequence of the gene ompA coding the outer membrane protein II of Escherichia coli K-12 [16].
• 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 [17].

Anatomical context of ompA

• In contrast, the E. coli O157:H7 ompA and tdcA ompA mutant strains were only slightly affected in adhesion to Caco-2 cells and during biofilm formation [18].
• More recently, Hfq was shown to affect the stability of several E. coli mRNAs, including ompA mRNA, where it interferes with ribosome binding, which in turn results in rapid degradation of the transcript [19].
• Genes contributing to invasion of brain microvascular endothelial cells include E. coli K1 genes ompA, ibeA, ibeB, and yijP [20].
• Active single-chain Fv molecules encoded by synthetic genes have been expressed and secreted to the periplasm of Escherichia coli using the ompA secretory signal [21].
• Complementation of OmpA- E. coli with a plasmid containing the ompA gene restored the ability of OmpA- E. coli to inhibit the apoptosis of infected macrophages, further demonstrating that E. coli OmpA expression is critical for inducing macrophage survival and thereby finding a safe haven for its growth [22].

Associations of ompA with chemical compounds

• In addition, deletion of ompA reduced biofilm mass by 80% in both LB medium and LB medium with glucose [23].
• The VH-linker-VL structure was blunt-cloned into expression vectors bearing the tryptophan promoter and pelB or ompA signal peptide sequences [24].
• Some individuals had antibodies reacting very strongly with the iron-regulated outer membrane proteins, including the ferric-enterochelin receptor protein (Mr, 81,000), as well as with ompA [25].
• The beta-lactam antibiotic cephalexin prevents the insertion of newly synthesized ompA protein into the poles but removal of the antibiotic allows the randomly dispersed protein to migrate to the polar and possibly the septal areas of the cell [26].

Physical interactions of ompA

• The SraD-mediated decay of ompA mRNA depends on Hfq and in vitro studies revealed that Hfq facilitates binding of the regulatory RNA to the translational initiation region of the messenger [2].

Other interactions of ompA

• Stable E. coli mRNAs such as lpp and ompA were drastically destabilized immediately after infection [17].
• Expression of lacZ from the ompA or by foreign ompA alleles which are not expressed in E. coli K-12 [27].
• Antisera were raised against the purified Escherichia coli K12 outer membrane proteins ompA-, ompC- and ompF proteins and protein e [28].
• An E. coli strain deleted for the ppk gene showed increased stability of the ompA mRNA [29].
• Deletion of sraD, however, does not significantly affect the stability of the ompA mRNA in slowly growing cells [2].

Analytical, diagnostic and therapeutic context of ompA

• The crystallization of outer membrane proteins from Escherichia coli. Studies on lamB and ompA gene products [30].
• 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 [31].
• 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 [32].
• First, morphometry and electron microscopy data showed that E. coli C386 (ompA lpp) cells harboring plasmid vector pEBH21 were rounded while cells of the same strain harboring p4A2HC2 (TpN50+), pWW2200 (OprF+), or pRD87 (OmpA+) were rod shaped [33].
• Autoradiography of cell envelope ghosts obtained from a strain of Escherichia coli which lacks two major outer membrane proteins has been used to demonstrate the polar concentration of another major outer membrane protein, ompA protein [26].

References