Primary structure of major outer membrane protein I of Escherichia coli B/r.

Chen, Robert; Kramer, C.; Schmidmayr, Waldtraud; Henning, Ulf

doi:10.1073/pnas.76.10.5014

Cited by 63 publications

(38 citation statements)

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“…In contrast to some other transmembrane proteins, outer membrane protein I (porin) does not contain a contiguous sequence of t20 hydrophobic residues that might span the membrane (15 (19,26). The DNA sequence did not agree, at four positions, with the amino acid sequence originally determined.…”

Section: Discussionmentioning

confidence: 96%

“…Finally, because of the striking repetitiveness of the outer membrane lipoprotein sequence (9), the sequence of protein II* and that previously published for protein 1 (15) have been tested for internal homologies and similarities between the two polypeptides by computer analysis (program RELATE performed by W. C. Barker, National Medical Research Foundation, Washington, DC) with the mutation data matrix (39,40,41). For protein I, no evidence for internal repetitiveness was found.…”

Section: Discussionmentioning

confidence: 99%

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Primary structure of major outer membrane protein II (ompA protein) of Escherichia coli K-12.

Chen¹,

Schmidmayr²,

Kramer³

et al. 1980

Proc. Natl. Acad. Sci. U.S.A.

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The amino acid sequence of major outer membrane protein II* (ompA protein) from Escherichia coli K-12 has been determined. The transmembrane polypeptide consists of 325 residues, resulting in a molecular weight of 35,159. The transmembrane part of the protein is located between residues 1 and 177. In Mis part of te rotein a predominantly lipophilic 27-residue segment exists that perhaps spans the membrane in a mostly a-helical conformation, or a 19-residue stretch of this segment might traverse the membrane linearly. Inside the outer membrane a sequence -Ala-Pro-AlaPro-Ala-Pro-Ala-Pro-exists that, analogous to the -Cys-Pro-ProCys-Pro-sequence in the hinge region of immunoglobulin, could assume the conformation of a polyproline helix. Computer analysis did not reveal a clear overall pattern of internal homology in the protein; besides the -Ala-Pro-repeat, only one local area (two adjacent dodeca eptide segments) shows some repetitiveness. The same analysis did not produce evidence for internal homology in the previously determined sequence of outer membrane protein I (porin) nor was any marked resemblance detected between transmembrane proteins I and II*.

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Section: Discussionmentioning

confidence: 96%

Section: Discussionmentioning

confidence: 99%

Primary structure of major outer membrane protein II (ompA protein) of Escherichia coli K-12.

Chen¹,

Schmidmayr²,

Kramer³

et al. 1980

Proc. Natl. Acad. Sci. U.S.A.

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150

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“…The amino acid composition of 190-kDa 4D is noteworthy because the molecule contains a greater percentage of hydrophobic amino acids (45%) than the E. coli surface proteins ompF (39%o) (6), ompA (39%) (7), and common pili (41%) (9) and the C. trachomatis major outer membrane protein (39%) (4). Evidence presented in this report demonstrates that in vitro self-assembly of 19-kDa monomers is the mechanism of ordered ring structure formation and is greatest at physiologic pH, suggesting that self-assembly of 4D occurs in vivo.…”

Section: Discussionmentioning

confidence: 99%

Properties of an ordered ring structure formed by recombinant Treponema pallidum surface antigen 4D

Fehniger¹,

Radolf²,

Lovett³

1986

J Bacteriol

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Ultrastructural and biochemical studies of a recombinant TreponemapaUidum surface antigen designated 4D have been conducted due to its likely biological significance. Electron microscopy demonstrated that the 190-kilodalton (kDa) 4D molecule is an ordered ring structure of 10-nm diameter. The 90-kDa proteinase K-treated 4D is an ordered ring structure of 6-nm diameter. Evidence is presented that the 190-kDa ordered ring is maintained by noncovalent bonds; 19-kDa monomers can reassociate in vitro to reform a 190-kDa molecule. Amino acid composition analysis of 190-kDa 4D showed that the molecule is composed of 45% hydrophobic residues. Evidence relating the structure of the 4D ordered ring to its potential role in the pathogenesis of syphilis is discussed.The inability to cultivate Treponema pallidum in defined media in vitro has hindered studies to biochemically define the molecules which contribute to its virulence. Purification of cloned T. pallidum proteins from Escherichia coli host cells has provided an opportunity to study the contribution of individual T. pallidum molecules to the pathogenesis of syphilis. We recently reported an initial characterization of a cloned T. pallidum protein, designated 4D, which has been purified to homogeneity from E. coli with yields in excess of 3 mg per liter of stationary-phase culture (10). The 4D molecule is a polymer of 19-kilodalton (kDa) monomers which has an apparent molecular weight of 190,000. Exhaustive treatment of 190-kDa 4D with proteinase K results in a homogeneous limit digestion product of 90 kDa, which retains specific reactivity with syphilitic sera. A 90-kDa molecule indistinguishable in size, charge (pI, 4.6), and antigenicity was isolated from proteinase K-treated T. pallidum, suggesting that the recombinant protein was very similar to the native 4D molecule. The MATERIALS AND METHODSSDS-PAGE and immunoblotfting. Vertical 1.5-mm-thick sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) slab resolving gels of 10%o total acrylamide with 1.3% cross-linking or linear gradient gels of 8 to 20%o total acrylamide with 2.6% cross-linking were prepared and run, using the discontinuous buffer systems and stacking gels previously described (10). Samples analyzed under denaturing conditions were mixed with an equal volume of a final sample buffer (FSB; plus 2-mercaptoethanol [2ME]) of 62.5 mM Tris (pH 6.8) containing 2% (wt/vol) SDS, 5% (vol/vol) 2ME, 20% (wt/vol) sucrose, and 0.1% bromphenol blue dye and then placed into a 100°C boiling-water bath for 10 min immediately before SDS-PAGE analysis. Other samples were mixed 1:2 in FSB or 67.2 mM Tris (pH 6.8) containing 4% (wt/vol) SDS, 20% (wt/vol) sucrose, and 0.01% (wt/vol) bromphenol blue dye, incubated at 37 or 25°C for 30 min, and then analyzed by SDS-PAGE (minimal denaturing conditions). Following electrophoresis, gels were either stained by Coomassie blue or immunoblotted and serologically probed as previously described (10).A two-dimensional gel system utilizing SDS-PAGE in both dimensi...

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“…The transmembrane regions of E. coli OmpF show limited sequence heterogeneity compared to OmpF sequences from other members of the family Enterobacteriaceae and compared to other E. coli porin molecules (OmpC, PhoE) (3,56). The comparison of known porin sequences from E. coli (11), Salmonella enterica serovar Typhimurium (39), S. enterica serovar Typhi (45), and Shigella flexneri 2a (67) 5. Identification of the minimal sequence recognized by T-cell hybridoma.…”

Section: Discussionmentioning

confidence: 99%

Identification of an I-E^d-Restricted T-Cell Epitope ofEscherichia coliOuter Membrane Protein F

Williams

Bigley

2004

Infect Immun

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A predominant T-cell epitope ofat either the C or the N terminus of the sequence was used, the minimal epitope was determined. Critical residues were determined by using alanine-substituted peptide analogues. T-cell hybridomas were only stimulated by peptides that encompassed amino acids 295 to 303 (9-mer), and the core sequence required a minimum of three additional amino acids at either the amino or the carboxy terminus to induce IL-2 secretion. Critical residues were determined to be phenylalanine at position 295, threonine at position 300, and tyrosines at positions 301 and 302. This study is the first to identify a minimal T-cell epitope and major histocompatibility complex restriction element of the OmpF protein and confirms previous observations that there is considerable degeneracy in the length of peptides that can bind I-E d and variability in the amino acid composition of the C and N termini of these peptides. Antigen recognition by CD4ϩ T cells involves the uptake and proteolysis of native proteins by antigen-presenting cells, followed by the association and surface presentation of smaller peptide fragments bound to class II major histocompatibility complex (MHC) molecules. Interaction of this complex with clonotypic receptors on the surface of T cells results in a cascade of intracellular events collectively termed T-cell activation. Acid elution, followed by protein sequencing of naturally processed peptides from affinity-purified human and murine class II molecules (13,14,17,29,41,47,64,65), has shown considerable variability in the length of bound peptides (11 to 17 amino acids in length) and that a single determinant may be presented as multiple peptide species, depending on the length of the amino-or carboxy-terminal flanking residues. Crystallographic analysis of the MHC class II molecule HLA-DR1 (9, 62) provided the structural explanation for the heterogeneity in length of class II-bound peptides since it was observed that peptides are bound in an extended conformation inside the binding groove, which is open at both ends, unlike the class I peptide-binding groove. Additionally, binding studies have revealed that peptide anchor residues (or their respective binding sites within the groove) are more degenerate in their specificity compared to the stringent binding of class I ligands. While allele-specific binding motifs for class II molecules have been more difficult to identify because of the open-ended structure of the peptide-binding groove and the resulting heterogeneity of bound peptides, several allele-specific motifs have emerged (http://syfpeithi.bmi-heidelberg.com/).Porins are a family of heterotrimeric pore-forming molecules present in the outer membranes of gram-negative members of the family Enterobacteriaceae. Monomeric porin molecules associate to form stable trimeric hydrophilic transmembrane channels that allow passive diffusion of solutes, including antibiotics, across the lipid bilayer. The primary amino acid sequence of porins from several species of the family Enterobacteri...

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Primary structure of major outer membrane protein I of Escherichia coli B/r.

Cited by 63 publications

References 48 publications

Primary structure of major outer membrane protein II (ompA protein) of Escherichia coli K-12.

Primary structure of major outer membrane protein II (ompA protein) of Escherichia coli K-12.

Properties of an ordered ring structure formed by recombinant Treponema pallidum surface antigen 4D

Identification of an I-E^d-Restricted T-Cell Epitope ofEscherichia coliOuter Membrane Protein F

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Primary structure of major outer membrane protein I of Escherichia coli B/r.

Cited by 63 publications

References 48 publications

Primary structure of major outer membrane protein II (ompA protein) of Escherichia coli K-12.

Primary structure of major outer membrane protein II (ompA protein) of Escherichia coli K-12.

Properties of an ordered ring structure formed by recombinant Treponema pallidum surface antigen 4D

Identification of an I-Ed-Restricted T-Cell Epitope ofEscherichia coliOuter Membrane Protein F

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Identification of an I-E^d-Restricted T-Cell Epitope ofEscherichia coliOuter Membrane Protein F