Temperate Stutzerimonas Phage Encoding Toxin-Antitoxin System Genes Represents a Novel Genus
摘要
Stutzerimonas have been extensively studied due to their remarkable metabolic and physiological diversity. However, research on its phages is currently limited. In this study, we isolated a novel double-stranded DNA (dsDNA) phage, vB_SstM-PG1, from the marine environment that infects Stutzerimonas stutzeri G1. Its dsDNA genome is 37204 bp long with a G/C content of 64.14% and encodes 54 open reading frames. The phage possesses a tail packaging structure that is different from known Stutzerimonas stutzeri phages and exhibits structural protein characteristics similar to those of temperate phages. In addition, two genes of toxin-antitoxin system, including YdaS_antitoxin and HEPN_SAV_6107, were found in the vB_SstM-PG1 genome and play important roles in regulating host growth and metabolism. With phylogenetic tree and comparative genomic analysis, it has been determined that vB_ SstM-PG1 is not closely related to any phages previously identified in the GenBank database. Instead, it has a connection with enigmatic, uncultured viruses. Specifically, the vB_SstM-PG1 virus exhibits an average nucleotide identity of over 70% with six uncultivated viruses identified in the IMG/VR v4 database. This significant finding has resulted in the identification of a novel viral genus known as Metabovirus.