Isolation and characterization of the newStreptomycesphages Kamino, Geonosis, Abafar and Scarif infecting a broad range of host species

Abstract

Streptomyces, a multifaceted genus of soil-dwelling bacteria within the phylum Actinobacteria, features intricate phage-host interactions shaped by its complex life cycle and the synthesis of a diverse array of specialized metabolites. Here, we describe the isolation and characterization of four novelStreptomycesphages infecting a variety of different host species. While phage Kamino, isolated onStreptomyces kasugaensis, is predicted to be temperate and encodes a serine integrase in its genome, phages Geonosis (isolated onS. griseus) and phages Abafar and Scarif, isolated onS. albidoflavus, are virulent phages. Phages Kamino and Geonosis were shown to amplify well in liquid culture leading to a pronounced culture collapse already at low titres. Determination of the host range by testing >40 differentStreptomycesspecies identified phages Kamino, Abafar and Scarif as broad host range phages, with Kamino showing productive infections on 15 different species. Isolated phages were further tested regarding their sensitivity to antiphage molecules. Here, the strongest effects were observed for the DNA-intercalating molecule daunorubicin. Overall, the phages described in this study expand the publicly available portfolio of phages infectingStreptomycesand will be instrumental for advancing the mechanistic understanding of the intricate antiviral strategies employed by these multicellular bacteria.