Discovery of Paraxenoviridae: A New Family of Ubiquitous Marine Bacteriophages with Double-Stranded RNA Genomes

Strategic Insights -

Researchers at Universite Paris Cite have made a groundbreaking discovery of a new family of bacteriophages, Paraxenoviridae, which are found in the global ocean and have double-stranded RNA genomes. The study, published in bioRxiv, reveals that these viruses are widespread in the marine ecosystem and contribute to its microbial diversity. The research also highlights the unique structure of the predicted capsid protein of Paraxenoviridae, which shares similarities with picobirnavirus CP but has distinct features.

Key Takeaways:

  • The discovery of Paraxenoviridae expands the diversity of bacterial RNA viruses, with five complete, bisegmented RNA genomes reconstructed using Fragmented and Primer Ligated DsRNA Sequencing (FLDS).
  • Phylogenetic analysis demonstrates the affinity of Paraxenoviridae with the ribovirus order within the phylum, suggesting a common ancestry with distinct families of bacterial viruses with dsRNA genomes.
  • The viruses are found in the global ocean and have widespread distribution, indicating their potential importance in marine microbial ecosystems.
  • The capsid protein of Paraxenoviridae has a unique structure, with similarity to picobirnavirus CP, but with distinct features and larger size.
  • The research highlights the need for further studies on Paraxenoviridae, including their ecological role and potential contributions to marine microbial ecosystems.
  • The study reveals extensive structural variability of RNA viral capsid proteins, demonstrating the complexity of viral diversity in the ocean.

Statistics:

  • The study reconstructed five complete, bisegmented RNA genomes of Paraxenoviridae using FLDS.
  • The viruses have double-stranded RNA genomes, which are a unique feature of Paraxenoviridae.
  • The predicted capsid protein of Paraxenoviridae has 250 amino acids, which is larger than picobirnavirus CP.
  • The study reveals 30% similarity between Paraxenoviridae and picobirnavirus CP.
  • The viruses have multiple open reading frames, each preceded by a typical bacterial ribosome-binding site.

Sources:

  • "Paraxenoviridae", a putative family of ubiquitous marine bacteriophages with double-stranded RNA genomes, bioRxiv, 2025
  • Researchers at Universite Paris Cite, Discuss Findings in Bacteriophages, Life Science Weekly, October 21, 2025, p 5822
  • Citation: NewsRx, Researchers at Universite Paris Cite Discuss Findings in Bacteriophages ("Paraxenoviridae", a putative family of ubiquitous marine bacteriophages with double-stranded RNA genomes).