Multiple roles of genome-attached bacteriophage terminal proteins

Redrejo-Rodríguez, Modesto; Salas, Margarita

doi:10.1016/j.virol.2014.08.003

Cited by 19 publications

(20 citation statements)

References 83 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such genes are generally located near the polymerase gene but very poorly conserved. Terminal proteins share features like a small size and a high isoelectric point [72,73]. Based on these criteria, IDF_05 appears the best candidate (Table S4) but additional investigations are needed to confirm this hypothesis.…”

Section: Resultsmentioning

confidence: 99%

Enterococcus faecalis Countermeasures Defeat a Virulent Picovirinae Bacteriophage

Lossouarn

Briet

Moncaut

et al. 2019

Viruses

View full text Add to dashboard Cite

Enterococcus faecalis is an opportunistic pathogen that has emerged as a major cause of nosocomial infections worldwide. Many clinical strains are indeed resistant to last resort antibiotics and there is consequently a reawakening of interest in exploiting virulent phages to combat them. However, little is still known about phage receptors and phage resistance mechanisms in enterococci. We made use of a prophageless derivative of the well-known clinical strain E. faecalis V583 to isolate a virulent phage belonging to the Picovirinae subfamily and to the P68 genus that we named Idefix. Interestingly, most isolates of E. faecalis tested—including V583—were resistant to this phage and we investigated more deeply into phage resistance mechanisms. We found that E. faecalis V583 prophage 6 was particularly efficient in resisting Idefix infection thanks to a new abortive infection (Abi) mechanism, which we designated Abiα. It corresponded to the Pfam domain family with unknown function DUF4393 and conferred a typical Abi phenotype by causing a premature lysis of infected E. faecalis. The abiα gene is widespread among prophages of enterococci and other Gram-positive bacteria. Furthermore, we identified two genes involved in the synthesis of the side chains of the surface rhamnopolysaccharide that are important for Idefix adsorption. Interestingly, mutants in these genes arose at a frequency of ~10−4 resistant mutants per generation, conferring a supplemental bacterial line of defense against Idefix.

show abstract

Section: Resultsmentioning

confidence: 99%

Enterococcus faecalis Countermeasures Defeat a Virulent Picovirinae Bacteriophage

Lossouarn

Briet

Moncaut

et al. 2019

Viruses

View full text Add to dashboard Cite

show abstract

“…The proteins responsible for this are covalently linked to the phage genome ends and contain eukaryotic nuclear localization signals that promote their accumulation in the nucleus. Once inside the eukaryotic cell, these terminal proteins provide mechanism for localizing foreign DNA for gene expression or even integration into the cell genome 17 , 63 . Our pulse-chase experiment showed that the internalized phages could be recovered from the cells in their infective form up to 24 h, followed by an effective inactivation of phages within the cells.…”

Section: Discussionmentioning

confidence: 99%

Internalization of a polysialic acid-binding Escherichia coli bacteriophage into eukaryotic neuroblastoma cells

et al. 2017

View full text Add to dashboard Cite

Eukaryotic organisms are continuously exposed to bacteriophages, which are efficient gene transfer agents in bacteria. However, bacteriophages are considered not to pass the eukaryotic cell membrane and enter nonphagocytic cells. Here we report the binding and penetration of Escherichia coli PK1A2 bacteriophage into live eukaryotic neuroblastoma cells in vitro. The phage interacts with cell surface polysialic acid, which shares structural similarity with the bacterial phage receptor. Using fluorescence and electron microscopy, we show that phages are internalized via the endolysosomal route and persist inside the human cells up to one day without affecting cell viability. Phage capsid integrity is lost in lysosomes, and the phage DNA is eventually degraded. We did not detect the entry of phage DNA into the nucleus; however, we speculate that this might occur as a rare event, and propose that this potential mechanism could explain prokaryote–eukaryote gene flow.

show abstract

“…This study reports a survey of phages of AAB collected from grapes which resulted in the isolation and sequencing of a novel phage infecting G. cerinus , representing a novel member of the family Tectiviridae . Tectiviruses have tailless virions consisting of an icosahedrally organized proteinaceous capsid that surrounds a protein-rich lipid membrane, enclosing a linear double-stranded (ds) DNA genome with inverted terminal repeats and covalently attached terminal proteins [ 18 , 19 , 20 , 21 , 22 ]. Currently known tectiviruses are classified into two genera, Alphatectivirus and Betatectivirus [ 23 ].…”

Section: Introductionmentioning

confidence: 99%

Bacteriophage GC1, a Novel Tectivirus Infecting Gluconobacter Cerinus, an Acetic Acid Bacterium Associated with Wine-Making

Philippe

Krupovìč

Jaomanjaka

et al. 2018

Viruses

View full text Add to dashboard Cite

The Gluconobacter phage GC1 is a novel member of the Tectiviridae family isolated from a juice sample collected during dry white wine making. The bacteriophage infects Gluconobacter cerinus, an acetic acid bacterium which represents a spoilage microorganism during wine making, mainly because it is able to produce ethyl alcohol and transform it into acetic acid. Transmission electron microscopy revealed tail-less icosahedral particles with a diameter of ~78 nm. The linear double-stranded DNA genome of GC1 (16,523 base pairs) contains terminal inverted repeats and carries 36 open reading frames, only a handful of which could be functionally annotated. These encode for the key proteins involved in DNA replication (protein-primed family B DNA polymerase) as well as in virion structure and assembly (major capsid protein, genome packaging ATPase (adenosine triphosphatase) and several minor capsid proteins). GC1 is the first tectivirus infecting an alphaproteobacterial host and is thus far the only temperate tectivirus of gram-negative bacteria. Based on distinctive sequence and life-style features, we propose that GC1 represents a new genus within the Tectiviridae, which we tentatively named “Gammatectivirus”. Furthermore, GC1 helps to bridge the gap in the sequence space between alphatectiviruses and betatectiviruses.

show abstract

Multiple roles of genome-attached bacteriophage terminal proteins

Cited by 19 publications

References 83 publications

Enterococcus faecalis Countermeasures Defeat a Virulent Picovirinae Bacteriophage

Enterococcus faecalis Countermeasures Defeat a Virulent Picovirinae Bacteriophage

Internalization of a polysialic acid-binding Escherichia coli bacteriophage into eukaryotic neuroblastoma cells

Bacteriophage GC1, a Novel Tectivirus Infecting Gluconobacter Cerinus, an Acetic Acid Bacterium Associated with Wine-Making

Contact Info

Product

Resources

About