DNA sequence heterogeneity in the genes of T-even type Escherichia coli phages encoding the receptor recognizing protein of the long tail fibers

1984 ◽  
Vol 195 (1-2) ◽  
pp. 144-152 ◽  
Author(s):  
Isolde Riede ◽  
Marie-Luise Eschbach ◽  
Ulf Henning
Keyword(s):  
Escherichia Coli ◽  
Dna Sequence ◽  
Long Tail ◽  
Sequence Heterogeneity ◽  
Tail Fibers

scholarly journals Evaluating Phage Tail Fiber Receptor-Binding Proteins Using a Luminescent Flow-Through 96-Well Plate Assay

2021 ◽  
Vol 12 ◽  
Author(s):  
Emma L. Farquharson ◽  
Ashlyn Lightbown ◽  
Elsi Pulkkinen ◽  
Téa Russell ◽  
Brenda Werner ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Host Range ◽  
Infection Process ◽  
Bacterial Disease ◽  
Tail Fiber ◽  
Long Tail ◽  
Bacterial Surface ◽  
Specific Phage ◽  
Phage Tail ◽  
Tail Fibers

Phages have demonstrated significant potential as therapeutics in bacterial disease control and as diagnostics due to their targeted bacterial host range. Host range has typically been defined by plaque assays; an important technique for therapeutic development that relies on the ability of a phage to form a plaque upon a lawn of monoculture bacteria. Plaque assays cannot be used to evaluate a phage’s ability to recognize and adsorb to a bacterial strain of interest if the infection process is thwarted post-adsorption or is temporally delayed, and it cannot highlight which phages have the strongest adsorption characteristics. Other techniques, such as classic adsorption assays, are required to define a phage’s “adsorptive host range.” The issue shared amongst all adsorption assays, however, is that they rely on the use of a complete bacteriophage and thus inherently describe when all adsorption-specific machinery is working together to facilitate bacterial surface adsorption. These techniques cannot be used to examine individual interactions between a singular set of a phage’s adsorptive machinery (like long tail fibers, short tail fibers, tail spikes, etc.) and that protein’s targeted bacterial surface receptor. To address this gap in knowledge we have developed a high-throughput, filtration-based, bacterial binding assay that can evaluate the adsorptive capability of an individual set of a phage’s adsorption machinery. In this manuscript, we used a fusion protein comprised of an N-terminal bioluminescent tag translationally fused to T4’s long tail fiber binding tip (gp37) to evaluate and quantify gp37’s relative adsorptive strength against the Escherichia coli reference collection (ECOR) panel of 72 Escherichia coli isolates. Gp37 could adsorb to 61 of the 72 ECOR strains (85%) but coliphage T4 only formed plaques on 8 of the 72 strains (11%). Overlaying these two datasets, we were able to identify ECOR strains incompatible with T4 due to failed adsorption, and strains T4 can adsorb to but is thwarted in replication at a step post-adsorption. While this manuscript only demonstrates our assay’s ability to characterize adsorptive capabilities of phage tail fibers, our assay could feasibly be modified to evaluate other adsorption-specific phage proteins.

scholarly journals Manipulating interactions between T4 phage long tail fibers and Escherichia coli receptors

2021 ◽  
Author(s):  
Akiyo Suga ◽  
Marina Kawaguchi ◽  
Tetsuro Yonesaki ◽  
Yuichi Otsuka
Keyword(s):  
Escherichia Coli ◽  
Host Specificity ◽  
Protein C ◽  
Phage Therapy ◽  
Bacteriophage T4 ◽  
O157 Strain ◽  
Long Tail ◽  
E Coli ◽  
T4 Phage ◽  
Tail Fibers

Bacteriophages are the most abundant and diverse biological entities on Earth. Phages exhibit strict host specificity that is largely conferred by adsorption. However, the mechanism underlying this phage–host specificity remains poorly understood. In this study, we examined the interaction between outer membrane protein C (OmpC), one of the Escherichia coli receptors, and the long tail fibers of bacteriophage T4. T4 phage uses OmpC of the K12 strain, but not of the O157 strain, for adsorption, even though OmpC from the two E. coli strains share 94% homology. We identified amino acids P177 and F182 in Loop 4 of the K12 OmpC as essential for T4 phage adsorption in the copresence of Loop 1 and Loop 5. Analyses of phage mutants capable of adsorbing to OmpC mutants demonstrated that amino acids at positions 937 and 942 of the gp37 protein, which is present in the digital tip (DT) region of the T4 long tail fibers, play an important role in adsorption. Furthermore, we created a T4 phage mutant library with artificial modifications in the DT region and isolated and characterized multiple phage mutants capable of adsorbing to OmpC of the O157 strain or lipopolysaccharide of the K12 strain. These results shed light on the mechanism underlying the phage–host specificity mediated by gp37 and OmpC and may be useful in the development of phage therapy via artificial modifications of the DT region of T4 phage. IMPORTANCE Understanding the host specificity of phages will lead to the development of phage therapy. The interaction between outer membrane protein C (OmpC), one of the Escherichia coli receptors, and the gp37 protein composing the digital tip (DT) region of the long tail fibers of bacteriophage T4 largely determines its host specificity. Here, we elucidated the amino acid residues important for the interaction between gp37 and OmpC. This result suggests that the shapes of both proteins at the binding interface play important roles in their interactions, which is likely mediated by multiple residues of both binding partners. Additionally, we successfully isolated multiple phage mutants capable of adsorbing to a variety of E. coli receptors using a mutant T4 phage library with artificial modifications in the DT region, providing a foundation for the alteration of the host specificity.

scholarly journals Characterization of the interactions between Escherichia coli receptors, LPS and OmpC, and bacteriophage T4 long tail fibers

2016 ◽  
Vol 5 (6) ◽  
pp. 1003-1015 ◽  
Author(s):  
Ayaka Washizaki ◽  
Tetsuro Yonesaki ◽  
Yuichi Otsuka
Keyword(s):  
Escherichia Coli ◽  
Bacteriophage T4 ◽  
Long Tail ◽  
Tail Fibers

scholarly journals Further tests of a recombination model in which chi removes the RecD subunit from the RecBCD enzyme of Escherichia coli.

Genetics ◽  
1990 ◽  
Vol 126 (3) ◽  
pp. 519-533 ◽  
Author(s):  
F W Stahl ◽  
L C Thomason ◽  
I Siddiqi ◽  
M M Stahl
Keyword(s):  
Escherichia Coli ◽  
Dna Sequence ◽  
Dna Packaging ◽  
Lambda Phage ◽  
Recombination Model ◽  
Phage Types ◽  
Point Of Entry ◽  
Reciprocal Recombination ◽  
Recbcd Enzyme ◽  
Lambda Dna

Abstract When one of two infecting lambda phage types in a replication-blocked cross is chi + and DNA packaging is divorced from the RecBCD-chi interaction, complementary chi-stimulated recombinants are recovered equally in mass lysates only if the chi + parent is in excess in the infecting parental mixture. Otherwise, the chi 0 recombinant is recovered in excess. This observation implies that, along with the chi 0 chromosome, two chi + parent chromosomes are involved in the formation of each chi + recombinant. The trimolecular nature of chi +-stimulated recombination is manifest in recombination between lambda and a plasmid. When lambda recombines with a plasmid via the RecBCD pathway, the resulting chromosome has an enhanced probability of undergoing lambda x lambda recombination in the interval into which the plasmid was incorporated. These two observations support a model in which DNA is degraded by Exo V from cos, the sequence that determines the end of packaged lambda DNA and acts as point of entry for RecBCD enzyme, to chi, the DNA sequence that stimulates the RecBCD enzyme to effect recombination. The model supposes that chi acts by ejecting the RecD subunit from the RecBCD enzyme with two consequences. (1) ExoV activity is blocked leaving a highly recombinagenic, frayed duplex end near chi, and (2) as the enzyme stripped of the RecD subunit travels beyond chi it is competent to catalyze reciprocal recombination.

DNA sequence analysis of the composite plasmid pTC conferring virulence and antimicrobial resistance for porcine enterotoxigenic Escherichia coli

2012 ◽  
Vol 302 (1) ◽  
pp. 4-9 ◽  
Author(s):  
Péter Z. Fekete ◽  
Elzbieta Brzuszkiewicz ◽  
Gabriele Blum-Oehler ◽  
Ferenc Olasz ◽  
Mónika Szabó ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Sequence Analysis ◽  
Antimicrobial Resistance ◽  
Dna Sequence ◽  
Dna Sequence Analysis ◽  
Enterotoxigenic Escherichia Coli
Sign in / Sign up

Export Citation Format

Share Document