Soft rot pathogenDickeya dadantii3937 produces tailocins resembling the tails ofEnterobacteriabacteriophage P2

Abstract

AbstractTailocins are nanomolecular machines with bactericidal activity. They are produced by bacteria to contribute to fitness in mixed communities, and hence, they play a critical role in their ecology in a variety of habitats. Here, we characterized the new tailocin produced byDickeya dadantiistrain 3937, a well-characterized member of plant pathogenic Soft RotPectobacteriaceae(SRP). Tailocins induced inD. dadantiiwere ca. 166 nm long tubes surrounded by contractive sheaths with baseplates having tail fibers at one end. A 22-kb genomic cluster involved in their synthesis and having high homology to the cluster coding for the tail of the Enterobacteriophage P2 was identified. TheD. dadantiitailocins, termed dickeyocin P2D1 (phage P2-like dickeyocin 1), were resistant to inactivation by pH (3.5 – 12), temperature (4 – 50 °C), and elevated osmolarity (NaCl concentration: 0.01 – 1 M). P2D1 could kill a variety of differentDickeyaspp. but not any strain ofPectobacteriumspp. tested and were not toxic toCaenorhabditis elegans.TeaserTailocins are nanomolecular entities similar to syringes that are produced by various bacteria to fight other microorganisms present in the same environment.