Isolation of Salmonella Phage and its Ability to Control Pathogenic Salmonella in Peeled and Deveined Shrimp

The Yersinia bacteriophages fPS-2, fPS-65, and fPS-90, isolated from pig stools, have long contractile tails and elongated heads, and they belong to genus Tequatroviruses in the order Caudovirales. The phages exhibited relatively wide host ranges among Yersinia pseudotuberculosis and related species. One-step growth curve experiments revealed that the phages have latent periods of 50–80 min with burst sizes of 44–65 virions per infected cell. The phage genomes consist of circularly permuted dsDNA of 169,060, 167,058, and 167,132 bp in size, respectively, with a G + C content 35.3%. The number of predicted genes range from 267 to 271. The phage genomes are 84–92% identical to each other and ca 85% identical to phage T4. The phage receptors were identified by whole genome sequencing of spontaneous phage-resistant mutants. The phage-resistant strains had mutations in the ompF, galU, hldD, or hldE genes. OmpF is a porin, and the other genes encode lipopolysaccharide (LPS) biosynthetic enzymes. The ompF, galU, and hldE mutants were successfully complemented in trans with respective wild-type genes. The host recognition was assigned to long tail fiber tip protein Gp38, analogous to that of T-even phages such as Salmonella phage S16, specifically to the distal β-helices connecting loops.

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Salmonella Bacteriophage Diversity According to Most Prevalent Salmonella Serovars in Layer and Broiler Poultry Farms from Eastern Spain

Animals ◽

10.3390/ani10091456 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1456

Author(s):

Sandra Sevilla-Navarro ◽

Pablo Catalá-Gregori ◽

Clara Marin

Keyword(s):

Point Of View ◽

Poultry Production ◽

Poultry Products ◽

Production Type ◽

Poultry Farms ◽

Commercial Poultry ◽

Salmonella Serovars ◽

The Impact ◽

Phage Isolation ◽

Salmonella Phage

The exploration of novel nonantibiotic interventions in the field, such as the use of bacteriophages, is necessary to avoid the presence of Salmonella. Bacteriophages are a group of viruses widely distributed in nature, strictly associated with the prokaryotic cell. Researchers have demonstrated the success of phage therapy in reducing Salmonella counts in poultry products. However, the impact that phage concentration in the environment may have against certain Salmonella serovars is not well understood. Therefore, the aim of this study was to assess Salmonella phage prevalence in commercial poultry farms in terms of the production type: layers or broilers. The most prevalent Salmonella serovars isolated in poultry production were used for phage isolation. Salmonella specific phages were isolated from 141 layer and broiler farms located in the Valencia region during 2019. Analysis of the samples revealed that 100% presented Salmonella phages, the most prevalent being against serovar S. Enteritidis (93%), followed by S. Virchow (59%), S. Typhimurium (55%), S. Infantis (52%) and S. Ohio (51%). These results indicate that poultry farms could represent an important source of Salmonella phages. Nevertheless, further studies are needed to assess the epidemiology of phages against other serovars present in other countries and their diversity from the point of view of molecular studies.

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Investigation of Salmonella Phage–Bacteria Infection Profiles: Network Structure Reveals a Gradient of Target-Range from Generalist to Specialist Phage Clones in Nested Subsets

Viruses ◽

10.3390/v13071261 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1261

Author(s):

Khatuna Makalatia ◽

Elene Kakabadze ◽

Nata Bakuradze ◽

Nino Grdzelishvili ◽

Ben Stamp ◽

...

Keyword(s):

Host Range ◽

Salmonella Enterica ◽

Target Range ◽

Nested Subsets ◽

Specific Phage ◽

Salmonella Infections ◽

Specialist Species ◽

Host Infection ◽

Salmonella Phage

Bacteriophages that lyse Salmonella enterica are potential tools to target and control Salmonella infections. Investigating the host range of Salmonella phages is a key to understand their impact on bacterial ecology, coevolution and inform their use in intervention strategies. Virus–host infection networks have been used to characterize the “predator–prey” interactions between phages and bacteria and provide insights into host range and specificity. Here, we characterize the target-range and infection profiles of 13 Salmonella phage clones against a diverse set of 141 Salmonella strains. The environmental source and taxonomy contributed to the observed infection profiles, and genetically proximal phages shared similar infection profiles. Using in vitro infection data, we analyzed the structure of the Salmonella phage–bacteria infection network. The network has a non-random nested organization and weak modularity suggesting a gradient of target-range from generalist to specialist species with nested subsets, which are also observed within and across the different phage infection profile groups. Our results have implications for our understanding of the coevolutionary mechanisms shaping the ecological interactions between Salmonella phages and their bacterial hosts and can inform strategies for targeting Salmonella enterica with specific phage preparations.

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A Salmonella Phage-P22 Mutant Defective in Abortive Transduction

Genetics ◽

10.1093/genetics/145.1.17 ◽

1997 ◽

Vol 145 (1) ◽

pp. 17-27 ◽

Cited By ~ 1

Author(s):

Nicholas R Benson ◽

John Roth

Keyword(s):

Protein S ◽

Lytic Infection ◽

Genetic Element ◽

Bacterial Dna ◽

Phage Mutant ◽

Viral Particles ◽

Phage Dna ◽

Phage P22 ◽

Mutant Locus ◽

Salmonella Phage

In the course of a lytic infection the Salmonella phage P22 occasionally encapsulates bacterial DNA instead of phage DNA. Thus, phage lysates include two classes of viral particles. Phage particles carrying bacterial DNA are referred to as transducing particles and deliver this DNA to a host as efficiently as particles carrying phage DNA. Once injected, the transduced DNA can either recombine with the recipient chromosome to form a “complete” transductant, or it can establish itself as an expressible, nonreplicating genetic element and form an “abortive” transductant. In this work, we describe a P22-phage mutant with reduced ability to form abortive transductants. The mutation responsible for this phenotype, called tdx-1, was found as one of two mutations contributing to the high-transducing phenotype of the P22-mutant HT12/4. In addition, the tdx-1 mutation is lethal when combined with an erf-am mutation. The tdx-1 mutation has been mapped to a region of the P22 genome that encodes several injected proteins and may involve more than one mutant locus. The phenotypes of the tdx-1 mutation suggest that the Tdx protein(s) normally assist in the circularization of the P22 genome and also contribute to the formation of DNA circles thought to be required for abortive transduction.

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Phage genes involved in the formation of generalized transducing particles in Salmonella-phage P22

MGG Molecular & General Genetics ◽

10.1007/bf00264784 ◽

1974 ◽

Vol 135 (2) ◽

pp. 175-184 ◽

Cited By ~ 37

Author(s):

A. Sudharsan Raj ◽

A. Yesoda Raj ◽

Horst Schmieger

Keyword(s):

Phage P22 ◽

Salmonella Phage

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REGIONAL SPECIFICITY OF ILLEGITIMATE RECOMBINATION BY THE TRANSLOCATABLE AMPLICILLIN-RESISTANCE ELEMENT Tn1 IN THE GENOME OF PHAGE P22

Genetics ◽

10.1093/genetics/92.3.685 ◽

1979 ◽

Vol 92 (3) ◽

pp. 685-710

Author(s):

George M Weinstock ◽

Miriam M Susskind ◽

David Botstein

Keyword(s):

Electron Microscopy ◽

Gene Function ◽

The Other ◽

Illegitimate Recombination ◽

Physical Analysis ◽

Irreversible Loss ◽

Ampicillin Resistance ◽

Regional Specificity ◽

Phage P22 ◽

Salmonella Phage

ABSTRACT Insertions of the translocatable ampicillin-resistance element Tnl were selected in the genome of the temperate Salmonella phage P22 by growing the phage on hosts carrying the resistance plasmid RP4. Insertions of Tnl into phage P22 are rare (10-10 per phage) and nonrandomly distributed in the P22 genome. They are found mainly in the vicinity of the P22 ant gene. Insertions within the ant gene are found at many (at least 15) genetically separable sites, are found equally frequently in both orientations and cause irreversible loss of gene function. Some insertions in ant appear to be associated with an adjecent deletion.—Prophage deletions were derived from P22::Tnl phages by two methods. Low multiplicity transductants have nonrandomly distributed endpoints. One end is at or very near the site of the Tnl insertion, and the other is in the vicinity of gene 12; however, there are many genetically distinguishable endpoints within gene 12. Prophage deletions selected as survivors of induction of a P22Ap mnt-ts lysogen have similarly nonrandom endpoints, with the Tnl-distal end frequently near the ant gene, as well as gene 12. Physical analysis of several prophage deletions suggests that the Tnl is intact to the resolution of DNA electron microscopy and that the deletions begin at the end of the Tnl insertion.—These results suggest that illegitimate recombination associated with Tnl shows regional specificity (i.e., preference for some large areas of the P22 genome over other areas), but that within these regions is quite nonspecific.

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