Identification of the Receptor-Binding Regions of pb5 Proteins of Bacteriophages T5 and BF23

Mondigler, Martin; Holz, Thomas; Heller, Knut J.

doi:10.1006/viro.1996.0218

Cited by 26 publications

(34 citation statements)

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“…These genomic homologies identified the H8 receptor-binding tail protein (Rbp), and its comparison to the T5 and BF23 receptor binding proteins revealed regions that likely interact with the OM proteins FepA, FhuA, and BtuB, respectively. These data support and refine prior predictions of the T5 receptor binding domain in the oad structural gene (63). The analogous portion of the H8 Rbp, from residues 138 to 213, has a net charge of Ϫ8, consistent with the experimental evidence that H8 interacts with FepA in a similar way as the acidic siderophore FeEnt.…”

supporting

confidence: 86%

“…For H8, the Rbp is most homologous to Hrs and pb5 (Oad) of BF23 and T5, respectively, and Tpf is related to the pb2 (D18-19) of T5. Despite the fact that the products of oad and hrs may functionally replace each other in the tails of T5 and BF23, respectively (39, 48), Mondigler et al (62,63) reported that no homology exists between these genes. The CLUSTAL W alignment of the T5, BF23, and H8 receptor binding proteins (Fig.…”

Section: Discussionmentioning

confidence: 99%

“…Besides the genome of H8, reported herein, full or partial genomic sequences of other LGP-specific bacteriophage are known, including those of the TonB-dependent phage T1 and the TonB-independent phages T5 and BF23. Sequence data for BF23 is incomplete, but the genes that encode some of its tail proteins are known and sequenced (62,63). Blast analyses of H8 DNA identified ORFs at 94.7 kb and 82.8 kb that encode homologous proteins to the experimentally demonstrated receptor binding proteins of BF23 (Hrs) (48) and T5 (pb5, encoded by oad) (39, 63) and the pore-forming tail proteins of T5 (pb2) (7,28), respectively.…”

Section: /67mentioning

confidence: 99%

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FepA- and TonB-Dependent Bacteriophage H8: Receptor Binding and Genomic Sequence

Rabsch

Wiley

et al. 2007

J Bacteriol

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H8 is derived from a collection of Salmonella enterica serotype Enteritidis bacteriophage. Its morphology and genomic structure closely resemble those of bacteriophage T5 in the family Siphoviridae. H8 infected S. enterica serotypes Enteritidis and Typhimurium and Escherichia coli by initial adsorption to the outer membrane protein FepA. Ferric enterobactin inhibited H8 binding to E. coli FepA (50% inhibition concentration, 98 nM), and other ferric catecholate receptors (Fiu, Cir, and IroN) did not participate in phage adsorption. H8 infection was TonB dependent, but exbB mutations in Salmonella or E. coli did not prevent infection; only exbB tolQ or exbB tolR double mutants were resistant to H8. Experiments with deletion and substitution mutants showed that the receptor-phage interaction first involves residues distributed over the protein's outer surface and then narrows to the same charged (R316) or aromatic (Y260) residues that participate in the binding and transport of ferric enterobactin and colicins B and D. These data rationalize the multifunctionality of FepA: toxic ligands like bacteriocins and phage penetrate the outer membrane by parasitizing residues in FepA that are adapted to the transport of the natural ligand, ferric enterobactin. DNA sequence determinations revealed the complete H8 genome of 104.4 kb. A total of 120 of its 143 predicted open reading frames (ORFS) were homologous to ORFS in T5, at a level of 84% identity and 89% similarity. As in T5, the H8 structural genes clustered on the chromosome according to their function in the phage life cycle. The T5 genome contains a large section of DNA that can be deleted and that is absent in H8: compared to T5, H8 contains a 9,000-bp deletion in the early region of its chromosome, and nine potentially unique gene products. Sequence analyses of the tail proteins of phages in the same family showed that relative to pb5 (Oad) of T5 and Hrs of BF23, the FepA-binding protein (Rbp) of H8 contains unique acidic and aromatic residues. These side chains may promote binding to basic and aromatic residues in FepA that normally function in the adsorption of ferric enterobactin. Furthermore, a predicted H8 tail protein showed extensive identity and similarity to pb2 of T5, suggesting that it also functions in pore formation through the cell envelope. The variable region of this protein contains a potential TonB box, intimating that it participates in the TonB-dependent stage of the phage infection process.Bacteriophage adsorb to components of the gram-negative bacterial outer membrane (OM) during the initial stages of their infectious processes (17,20,36,37,64,87,88,98). For example, phages Mu (84) and X174 (41) initially bind to lipopolysaccharide, whereas (95), T6 (86), and TLS (30) adsorb to the OM proteins LamB, Tsx, and TolC, respectively. T2 (53) and T4 (92, 102) utilize both lipopolysaccharide and surface proteins in their adsorption reactions. The surface receptor proteins are porins that nonspecifically (70, 71) or specifically (55, 56, 69) transport...

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supporting

confidence: 86%

Section: Discussionmentioning

confidence: 99%

Section: /67mentioning

confidence: 99%

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FepA- and TonB-Dependent Bacteriophage H8: Receptor Binding and Genomic Sequence

Rabsch

Wiley

et al. 2007

J Bacteriol

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“…Alternatively, the large size of the phage particles relative to the other ligands may in some manner preclude the enhancement of FhuA-TonB interaction as detected in vitro. The identification and isolation of tail fiber proteins that constitute the minimal requirement for phage to participate in receptor recognition (54,55) will assist in the analysis of TonB coupling with TonB-dependent receptors. Future studies need to focus upon the ligand-induced conformational dynamics of FhuA which govern its physical association with TonB and upon those regions of FhuA which are required for the interaction with TonB.…”

Section: Discussionmentioning

confidence: 99%

Cell Envelope Signaling in Escherichia coli

Moeck

Coulton

Postle

1997

Journal of Biological Chemistry

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The ferrichrome-iron receptor of Escherichia coli is FhuA, an outer membrane protein that is dependent upon the energy-coupling protein TonB to enable active transport of specific hydroxamate siderophores, infection by certain phages, and cell killing by the protein antibiotics colicin M and microcin 25. In vivo cross-linking studies were performed to establish at the biochemical level the interaction between FhuA and TonB. In an E. coli strain in which both proteins were expressed from the chromosome, a high molecular mass complex was detected when the ferrichrome homologue ferricrocin was added immediately prior to addition of crosslinker. The complex included both proteins; it was absent from strains of E. coli that were devoid of either FhuA or TonB, and it was detected with anti-FhuA and anti-TonB monoclonal antibodies. These results indicate that, in vivo, the binding of ferricrocin to FhuA enhances complex formation between the receptor and TonB. An in vitro system was established with which to examine the FhuA-TonB interaction. Incubation of TonB with histidine-tagged FhuA followed by addition of Ni 2؉ -nitrilotriacetate-agarose led to the specific recovery of both TonB and FhuA. Addition of ferricrocin or colicin M to FhuA in this system greatly increased the coupling between FhuA and TonB. Conversely, a monoclonal antibody that binds near the N terminus of FhuA reduced the retention of TonB by histidine-tagged FhuA. These studies demonstrate the significance of ligand binding at the external surface of the cell to mediate signal transduction across the outer membrane.

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“…However, this previous assignment must be revisited as pb2 is not long enough to extend from the bottom of the tail tube to the end of the central fiber (18). pb5, the receptor binding protein (RBP), ensures the binding of T5 to its receptor, the E. coli outer membrane protein FhuA (19,20). The FhuA-pb5 complex has been characterized in vitro (21)(22)(23), but the exact location of pb5 at the tail tip remains uncertain.…”

mentioning

confidence: 99%

Insights into Bacteriophage T5 Structure from Analysis of Its Morphogenesis Genes and Protein Components

Zivanovic

Confalonieri

Ponchon

et al. 2014

J Virol

104

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Bacteriophage T5 represents a large family of lytic Siphoviridae infecting Gram-negative bacteria. The low-resolution structure of T5 showed the T‫31؍‬ geometry of the capsid and the unusual trimeric organization of the tail tube, and the assembly pathway of the capsid was established. Although major structural proteins of T5 have been identified in these studies, most of the genes encoding the morphogenesis proteins remained to be identified. Here, we combine a proteomic analysis of T5 particles with a bioinformatic study and electron microscopic immunolocalization to assign function to the genes encoding the structural proteins, the packaging proteins, and other nonstructural components required for T5 assembly. A head maturation protease that likely accounts for the cleavage of the different capsid proteins is identified. Two other proteins involved in capsid maturation add originality to the T5 capsid assembly mechanism: the single head-to-tail joining protein, which closes the T5 capsid after DNA packaging, and the nicking endonuclease responsible for the single-strand interruptions in the T5 genome. We localize most of the tail proteins that were hitherto uncharacterized and provide a detailed description of the tail tip composition. Our findings highlight novel variations of viral assembly strategies and of virion particle architecture. They further recommend T5 for exploring phage structure and assembly and for deciphering conformational rearrangements that accompany DNA transfer from the capsid to the host cytoplasm. Bacteriophage T5 is a member of the Siphoviridae family infecting Escherichia coli. It consists of an icosahedral capsid containing a large molecule of double-stranded DNA (dsDNA) (121.75 kbp) attached to a long flexible noncontractile tail. The complete genomes of two wild-type T5 strains (GenBank accession numbers AY587007 [1] and AY543070) and of the heat-stable deletion mutant T5st0 (GenBank accession number AY692264 [this study]) have been sequenced. Moreover, the genomes of T5-related phages H8 (2), EPS7 (3), SPC35 (4), AKVF3 (5), pVp-1 (6), and My1 (7) exhibit high sequence similarity to T5. Of the 159 to 174 genes predicted in each genome, about 70 were assigned functions on the basis of similarity searches and/or previous genetic studies. Most of the identified genes are related to nucleotide metabolism, DNA replication, recombination, and various enzymatic functions. Despite the fact that the major structural proteins of T5 have been identified (8), the functions of 13 of the 23 late genes encoding the structural and morphogenesis proteins remain to be ascertained.The overall structure of T5 was solved by cryo-electron microscopy (cryo-EM) and image reconstruction (9). The large icosahedral capsid consists of the coat protein pb8, arranged as 11 pentamers at the vertices and 120 hexamers on the faces. The 12th vertex is occupied by a dodecamer of the portal protein pb7. The early events of T5 capsid assembly have been partly deciphered (10). The initial shell (prohead I) is assemb...

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Identification of the Receptor-Binding Regions of pb5 Proteins of Bacteriophages T5 and BF23

Cited by 26 publications

References 0 publications

FepA- and TonB-Dependent Bacteriophage H8: Receptor Binding and Genomic Sequence

FepA- and TonB-Dependent Bacteriophage H8: Receptor Binding and Genomic Sequence

Cell Envelope Signaling in Escherichia coli

Insights into Bacteriophage T5 Structure from Analysis of Its Morphogenesis Genes and Protein Components

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