Bacteriophages of Thermophilic ' Group' Bacteria-A Systematic Review, 2023 Update.

Bacteriophages associated with thermophiles are gaining increased attention due to their pivotal roles in various biogeochemical and ecological processes, as well as their applications in biotechnology and bionanotechnology. Although thermophages are not suitable for controlling bacterial infections in humans or animals, their individual components, such as enzymes and capsid proteins, can be employed in molecular biology and significantly contribute to the enhancement of human and animal health. Despite their significance, thermophages still remain underrepresented in the known prokaryotic virosphere, primarily due to limited in-depth investigations.

Characterization of Bacteriophage vB_PtoS_NIIg3.2-A Representative of a New Genus within Thermophilic Siphoviruses.

A high temperature-adapted bacteriophage, vB_PtoS_NIIg3.2 (NIIg3.2), was isolated in Lithuania from compost heaps using strain NIIg-3 as a host for phage propagation.

Bacteriophages from Compost Heaps: Representatives of Three New Genera within Thermophilic Siphoviruses.

We report a detailed characterization of five thermophilic bacteriophages (phages) that were isolated from compost heaps in Vilnius, Lithuania using strains as the hosts for phage propagation. The efficiency of plating experiments revealed that phages formed plaques from 45 to 80 °C. Furthermore, most of the phages formed plaques surrounded by halo zones, indicating the presence of phage-encoded bacterial exopolysaccharide (EPS)-degrading depolymerases.

A novel Staphylococcus phage, vB_Sau-RP15, and its application in contaminated milk.

The vB_Sau-RP15 phage, selected for its potential use as a phage treatment in milk, was isolated from raw milk using Staphylococcusaureus NP01 as the host. The host range test revealed that the phage was able to lyse 12 strains of Staph. aureus from raw milk.

Functionalized Protein Nanotubes Based on the Bacteriophage vB_KleM-RaK2 Tail Sheath Protein.

We report on the construction of functionalized nanotubes based on tail sheath protein 041 from vB_KleM-RaK2 bacteriophage. The truncated 041 protein (041Δ200) was fused with fluorescent proteins GFP and mCherry or amidohydrolase YqfB. The generated chimeric proteins were successfully synthesized in BL21 (DE3) cells and self-assembled into tubular structures.

Exploring Viral Diversity in a Gypsum Karst Lake Ecosystem Using Targeted Single-Cell Genomics.

Little is known about the diversity and distribution of viruses infecting green sulfur bacteria (GSB) thriving in euxinic (sulfuric and anoxic) habitats, including gypsum karst lake ecosystems. In this study, we used targeted cell sorting combined with single-cell sequencing to gain insights into the gene content and genomic potential of viruses infecting sulfur-oxidizing bacteria , obtained from water samples collected during summer stratification in gypsum karst Lake Kirkilai (Lithuania). In total, 82 viral contigs were bioinformatically identified in 62 single amplified genomes (SAGs) of .

Bacteriophage vB_PagS_AAS23: A Singleton of the Genus .

A cold-adapted siphovirus, vB_PagS_AAS23 (AAS23) was isolated in Lithuania using the strain AUR for the phage propagation. The double-stranded DNA genome of AAS23 (51,170 bp) contains 92 probable protein encoding genes, and no genes for tRNA. A comparative sequence analysis revealed that 25 of all AAS23 open reading frames (ORFs) code for unique proteins that have no reliable identity to database entries.

Nitrogen Flow in Diazotrophic Cyanobacterium Is Altered by Cyanophage Infection.

Viruses can significantly influence cyanobacteria population dynamics and activity, and through this the biogeochemical cycling of major nutrients. However, surprisingly little attention has been given to understand how viral infections alter the ability of diazotrophic cyanobacteria for atmospheric nitrogen fixation and its release to the environment. This study addressed the importance of cyanophages for net N assimilation rate, expression of nitrogenase reductase gene () and changes in nitrogen enrichment (N/N) in the diazotrophic cyanobacterium during infection by the cyanophage vB_AphaS-CL131.

Complete genome analysis of Pantoea agglomerans-infecting bacteriophage vB_PagM_AAM22.

A novel myovirus, vB_PagM_AAM22 (AAM22), was isolated in Lithuania using Pantoea agglomerans as the host for phage propagation. The 49,744-bp genome of AAM22 has a G + C content of 48.4% and contains 96 probable protein-encoding genes and no genes for tRNA.

Complete Genome Sequence of Bacillus cereus Bacteriophage vB_BceS_KLEB30-3S.

In this study, we present the genomic characterization of the temperate bacteriophage vB_BceS_KLEB30-3S (KLEB30-3S), which was induced from strain KR3M-30, isolated from a gypsum karst lake ecosystem in Lithuania. The 37,134-bp genome of KLEB30-3S contains 58 predicted protein-encoding genes and no tRNA genes.

-Infecting Bacteriophage vB_PagS_AAS21: A Cold-Adapted Virus Representing a Novel Genus within the Family .

A novel cold-adapted siphovirus, vB_PagS_AAS21 (AAS21), was isolated in Lithuania using as the host for phage propagation. AAS21 has an isometric head (~85 nm in diameter) and a non-contractile flexible tail (~174 × 10 nm). With a genome size of 116,649 bp, bacteriophage AAS21 is the largest -infecting siphovirus sequenced to date.

Self-Assembly of Tail Tube Protein of Bacteriophage vB_EcoS_NBD2 into Extremely Long Polytubes in and .

Nucleotides, peptides and proteins serve as a scaffold material for self-assembling nanostructures. In this study, the production of siphovirus vB_EcoS_NBD2 (NBD2) recombinant tail tube protein gp39 reached approximately 33% and 27% of the total cell protein level in and expression systems, respectively. A simple purification protocol allowed us to produce a recombinant gp39 protein with 85%⁻90% purity.

The Robust Self-Assembling Tubular Nanostructures Formed by gp053 from Phage vB_EcoM_FV3.

The recombinant phage tail sheath protein, gp053, from infecting myovirus vB_EcoM_FV3 (FV3) was able to self-assemble into long, ordered and extremely stable tubular structures (polysheaths) in the absence of other viral proteins. TEM observations revealed that those protein nanotubes varied in length (~10⁻1000 nm). Meanwhile, the width of the polysheaths (~28 nm) corresponded to the width of the contracted tail sheath of phage FV3.

Genomic Characterization of Cyanophage vB_AphaS-CL131 Infecting Filamentous Diazotrophic Cyanobacterium Reveals Novel Insights into Virus-Bacterium Interactions.

While filamentous cyanobacteria play a crucial role in food web dynamics and biogeochemical cycling of many aquatic ecosystems around the globe, the knowledge regarding the phages infecting them is limited. Here, we describe the complete genome of the virulent cyanophage vB_AphaS-CL131 (here, CL 131), a phage that infects the filamentous diazotrophic bloom-forming cyanobacterium in the brackish Baltic Sea. CL 131 features a 112,793-bp double-stranded DNA (dsDNA) genome encompassing 149 putative open reading frames (ORFs), of which the majority (86%) lack sequence homology to genes with known functions in other bacteriophages or bacteria.

Bacteriophage vB_PagS_Vid5: A Low-Temperature Siphovirus That Harbors a Cluster of Genes Involved in the Biosynthesis of Archaeosine.

A novel lowtemperature siphovirus, vB_PagS_Vid5 (Vid5), was isolated in Lithuania using isolate for the phage propagation. The 61,437 bp genome of Vid5 has a G⁻C content of 48.8% and contains 99 probable protein encoding genes and one gene for tRNA.

Insights into cyanophage-mediated dynamics of nodularin and other non-ribosomal peptides in Nodularia spumigena.

The effect of cyanophage infection and lysis on the dynamics of the hepatotoxin nodularin (NOD) and other non-ribosomal peptides (NRPs) produced by cyanobacteria is poorly understood. In this study, changes in concentration of NOD and other NRPs during cyanophage infection of the filamentous cyanobacteria Nodularia spumigena were assessed using incubation experiments. Viral infection and lysis were associated with a significant reduction (93% at the 96 h post infection) of N.

Molecular analysis of the low-temperature Escherichia coli phage vB_EcoS_NBD2.

A novel low-temperature Escherichia coli phage vB_EcoS_NBD2 was isolated in Lithuania from agricultural soil. With an optimum temperature for plating around 20 °C, vB_EcoS_NBD2 efficiently produced plaques on Escherichia coli NovaBlue (DE3) at a temperature range of 10-30 °C, yet failed to plate at temperatures above 35 °C. Phage vB_EcoS_NBD2 virions have a siphoviral morphology with an isometric head (65 nm in diameter), and a non-contractile flexible tail (170 nm).

Complete Genome Sequence of Phage vB_EcoM_Alf5.

Here, we announce the complete genome sequence of the myophage vB_EcoM_Alf5 belonging to the genus , whose members have not been comprehensively studied at the molecular level. Phage vB_EcoM_Alf5 infects K-12-derived laboratory strains and therefore is well suited for functional studies.

Molecular Analysis of Arthrobacter Myovirus vB_ArtM-ArV1: We Blame It on the Tail.

This is the first report on a myophage that infects A novel virus, vB_ArtM-ArV1 (ArV1), was isolated from soil using sp. strain 68b for phage propagation. Transmission electron microscopy showed its resemblance to members of the family : ArV1 has an isometric head (∼74 nm in diameter) and a contractile, nonflexible tail (∼192 nm).

Incomplete LPS Core-Specific Felix01-Like Virus vB_EcoM_VpaE1.

Bacteriophages represent a valuable source for studying the mechanisms underlying virus-host interactions. A better understanding of the host-specificity of viruses at the molecular level can promote various phage applications, including bacterial diagnostics, antimicrobial therapeutics, and improve methods in molecular biology. In this study, we describe the isolation and characterization of a novel coliphage, vB_EcoM_VpaE1, which has different host specificity than its relatives.

Characterization of a lytic cyanophage that infects the bloom-forming cyanobacterium Aphanizomenon flos-aquae.

Vb-AphaS-CL131 is a novel cyanosiphovirus that infects harmful Aphanizomenon flos-aquae. This cyanophage has an isometric head, 97 nm in diameter and a long, flexible non-contractile tail, 361 nm long. With a genome size of ~120 kb, it is the second largest cyanosiphovirus isolated to date.

Low-temperature bacterial viruses VR - a small but diverse group of E. coli phages.

The complete genome sequences of four low-temperature Escherichia coli-specific tevenviruses, vb_EcoM-VR5, vb_EcoM-VR20, vb_EcoM-VR25 and vb_EcoM-VR26, were determined. Genomic comparisons including recently described genomes of vb_EcoM-VR7 and JS98 as well as phage T4 allowed the identification of two genetic groups that were consistent with defined host-range phenotypes. Group A included the broad-host-range phages vb_EcoM-VR5 and JS98, while group B included vb_EcoM-VR7, vb_EcoM-VR20, vb_EcoM-VR25 and vb_EcoM-VR26, which all had somewhat limited host ranges.

Isolation and characterization of vB_ArS-ArV2 - first Arthrobacter sp. infecting bacteriophage with completely sequenced genome.

This is the first report on a complete genome sequence and biological characterization of the phage that infects Arthrobacter. A novel virus vB_ArS-ArV2 (ArV2) was isolated from soil using Arthrobacter sp. 68b strain for phage propagation.

Klebsiella phage vB_KleM-RaK2 - a giant singleton virus of the family Myoviridae.

At 346 kbp in size, the genome of a jumbo bacteriophage vB_KleM-RaK2 (RaK2) is the largest Klebsiella infecting myovirus genome sequenced to date. In total, 272 out of 534 RaK2 ORFs lack detectable database homologues. Based on the similarity to biologically defined proteins and/or MS/MS analysis, 117 of RaK2 ORFs were given a functional annotation, including 28 RaK2 ORFs coding for structural proteins that have no reliable homologues to annotated structural proteins in other organisms.