Abstract
BACKGROUND: Bacteriophages protect themselves against host-encoded defense systems through DNA modifications. This study introduces Erebus, a newly identified phage infecting Aminobacter niigataensis, a bacterium capable of mineralizing 2,6-dichlorobenzamide- a common pesticide metabolite. The use of such bacterial degraders has been proposed for the bioremediation of contaminated groundwater. However, the presence of bacteriophages targeting these degraders poses a potential challenge to the success of such strategies. MATERIALS AND METHODS: The Erebus phage was isolated and subjected to whole-genome sequencing. Phylogenetic analysis was performed to determine its taxonomic placement and genomic synteny. DNA modifications were identified using a combination of liquid chromatography-mass spectrometry (LC-MS) and Oxford Nanopore Technologies sequencing. Transmission electron microscopy was used to determine the phage morphology. RESULTS: Phylogenetic analysis revealed that Erebus belongs to an unclassified genus, showing high synteny with Rhizobium phages of the Kleczkowskaviridae family. The phage possesses a double-stranded DNA genome of 52,229 base pairs, which includes a functional 7-deazaguanine DNA-modification system. Nanopore sequencing and LC-MS analysis confirmed the presence of PreQ(0) modifications at novel GG and AG motifs, conferring resistance against multiple restriction endonucleases. CONCLUSIONS: This is the first report of a phage infecting the genus Aminobacter, highlighting the potential impact of bacteriophages on microbial biodegradation strategies. The findings underscore the importance of considering phage-host interactions when deploying bacterial degraders for environmental remediation.