Podophages are, by far, the least well studied of all the bacteriophages. Despite being classified together due to their short, noncontractile tails, there is a huge amount of diversity among members of this group. Of the podophages, the N4-like family is the least well studied structurally and is quite divergent from well-characterized podophages such as T7 and P22.
View Article and Find Full Text PDFNational science, technology, engineering, and mathematics education emphasizes science practices, such as hands-on learning. We describe a week-long activity where students participate in real-world scientific discovery, including "hunting" for bacteriophage in a variety of environmental samples. First, the students collect samples, then look for evidence of phage on "bait" bacteria, and finally amplify/purify the phages for further study.
View Article and Find Full Text PDFThe inaugural Junior Editorial Board (JEB) of consisted of 64 early-career researchers active from 2022 to 2023. The goal of the JEB was to train early-career researchers in the art of peer review under the guidance of experienced editors. JEB members gained hands-on experience in peer review by participating in modules detailing the publishing process through the lenses of the journal, editor, and reviewer.
View Article and Find Full Text PDFThe first critical step in a virus's infection cycle is attachment to its host. This interaction is precise enough to ensure the virus will be able to productively infect the cell, but some flexibility can be beneficial to enable coevolution and host range switching or expansion. Bacteriophage Sf6 utilizes a two-step process to recognize and attach to its host Shigella flexneri.
View Article and Find Full Text PDFBiochim Biophys Acta Biomembr
July 2022
Viruses rely on hosts for their replication: thus, a critical step in the infection process is identifying a suitable host cell. Bacterial viruses, known as bacteriophages or phages, often use receptor binding proteins to discriminate between susceptible and non-susceptible hosts. By being able to evade predation, bacteria with modified or deleted receptor-encoding genes often undergo positive selection during growth in the presence of phage.
View Article and Find Full Text PDFThe instability of genomes has been described, but how this instability causes phenotypic differences within the species is largely unknown and likely variable. We describe herein the genome of strain PE577, originally a clinical isolate, which exhibits several phenotypic differences compared to the model strain 2457T. Like many previously described strains of , PE577 lacks discernible, functional CRISPR and restriction-modification systems.
View Article and Find Full Text PDFNumerous bacteriophages-viruses of bacteria, also known as phages-have been described for hundreds of bacterial species. The Gram-negative species are close relatives of , yet relatively few previously described phages appear to exclusively infect this genus. Recent efforts to isolate phages have indicated these viruses are surprisingly abundant in the environment and have distinct genomic and structural properties.
View Article and Find Full Text PDFIn microviruses, 60 copies of the positively charged DNA binding protein J guide the single-stranded DNA genome into the icosahedral capsid. Consequently, ∼12% of the genome is icosahedrally ordered within virions. Although the internal volume of the ϕX174, G4, and α3 capsids are nearly identical, their genome lengths vary widely from 5,386 (ϕX174) to 6,067 (α3) nucleotides.
View Article and Find Full Text PDFBacteriophages are abundant in the environment, yet the vast majority have not been discovered or described. Many characterized bacteriophages infect a small subset of Enterobacteriaceae hosts. Despite its similarity to Escherichia coli, the pathogenic Shigella flexneri has relatively few known phages, which exhibit significant differences from many E.
View Article and Find Full Text PDFIn 2016, Michigan experienced the largest outbreak of shigellosis, a type of bacillary dysentery caused by spp., since 1988. Following this outbreak, we isolated 16 novel -infecting bacteriophages (viruses that infect bacteria) from environmental water sources.
View Article and Find Full Text PDFIn an earlier study, protein-based barriers to horizontal gene transfer were investigated by placing the bacteriophage G4 G gene, encoding the major spike protein, into the φX174 genome. The foreign G protein promoted off-pathway assembly reactions, resulting in a lethal phenotype. After three targeted genetic selections, one of two foreign spike proteins was productively integrated into the φX174 system: the complete G4 or a recombinant G4/φX174 protein (94% G4:6% φX174).
View Article and Find Full Text PDFThe Microviridae, comprised of ssDNA, icosahedral bacteriophages, are a model system for studying morphogenesis and the evolution of assembly. Historically limited to the φX174-like viruses, recent results demonstrate that this richly diverse family is broadly divided into two groups. The defining feature appears to be whether one or two scaffolding proteins are required for assembly.
View Article and Find Full Text PDFShared host cells can serve as melting pots for viral genomes, giving many phylogenies a web-like appearance due to horizontal gene transfer. However, not all virus families exhibit web-like phylogenies. Microviruses form three distinct clades, represented by φX174, G4, and α3.
View Article and Find Full Text PDFSingle-stranded DNA(ssDNA) viral life cycles must balance double-stranded DNA (dsDNA) and ssDNA biosynthesis. Previously published in vitro results suggest that microvirus C and host cell SSB proteins play antagonistic roles to achieve this balance. To investigate this in vivo, microvirus DNA replication was characterized in cells expressing cloned C or ssb genes, which would presumably alter the C:SSB protein ratios.
View Article and Find Full Text PDFRecent advances in redox proteomics have provided significant insight into the role of oxidative modifications in cellular signalling and metabolism. At present, these techniques rely heavily on Western blots to visualize the oxidative modification and corresponding two dimensional (2D) gels for detection of total protein levels, resulting in the duplication of efforts. A major limitation associated with this methodology includes problematic matching up of gels and blots due to the differences in processing and/or image acquisition.
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