A Novel Broad Host Range Phage Infecting Alteromonas

Area of Science:

• Marine microbiology
• Virology
• Bacteriophage research

Background:

• Bacteriophages are crucial for marine bacterial mortality and biogeochemical cycles.
• Alteromonas phages (alterophages) are understudied despite the ecological importance of Alteromonas bacteria.
• Alteromonas bacteria provide ecological benefits by cross-protecting marine cyanobacteria.

Purpose of the Study:

• To characterize a novel alterophage, vB_AmeP-R8W (R8W), infecting deep-clade Alteromonas mediterranea.
• To investigate the biological and ecological features of R8W, including its host range and genomic properties.
• To contribute to understanding alterophage evolution and phage-host interactions.

Main Methods:

• Isolation and characterization of the novel alterophage vB_AmeP-R8W (R8W).
• Genomic sequencing and analysis of R8W, including identification of auxiliary metabolic genes.
• Host range determination through infection assays on various Alteromonas strains.
• Morphological analysis of R8W using electron microscopy.

Main Results:

• R8W, belonging to the Autographiviridae family, infects deep-clade Alteromonas mediterranea.
• R8W possesses an icosahedral head (65 nm) and short tail (12 nm), with a genome size of 48,825 bp (40.55% G+C).
• R8W exhibits a rapid lytic cycle (burst size 88 PFU/cell), a wide host range (35 Alteromonas strains), and specificity for deep-water isolates, attributed to specific receptor binding proteins and a holin-endolysin system.

Conclusions:

• The novel R8W alterophage provides insights into alterophage evolution and diversity.
• R8W's characteristics, including its wide host range and auxiliary metabolic genes, highlight its ecological significance.
• This study enhances understanding of phage-host interactions within marine microbial communities.