Prophylactic Application of Tailocins Prevents Infection byPseudomonas syringae

Abstract

Tailocins are phage-derived bacteriocins that demonstrate great potential as agricultural antimicrobials given their high killing efficiency and their precise strain-specific targeting ability. Our group has recently categorized and characterized tailocins produced by and tailocin sensitivities of the phytopathogen Pseudomonas syringae, and here we extend these experiments to test whether prophylactic tailocin application can prevent infection of Nicotiana benthamiana by P. syringae pv. syringae B728a. Specifically, we demonstrate that multiple strains can produce tailocins that prevent infection by strain B728a and engineer a deletion mutant to prove that tailocin targeting is responsible for this protective effect. Lastly, we provide evidence that heritable resistance mutations do not explain the minority of cases where tailocins fail to prevent infection. Our results extend previous reports of prophylactic use of tailocins against phytopathogens, and establish a model system with which to test and optimize tailocin application for prophylactic treatment to prevent phytopathogen infection.

Interspecies Killing Activity of Pseudomonas syringae Tailocins

“…The single colony was then grown overnight in KB media plus rifampicin and frozen in 40% glycerol at -80˚C. The creation of DBL1424 (a Rbp/chaperone deletion mutant of USA011R) and DBL1701 (a complementation strain derived from DBL1424) was described in (Baltrus et al 2022). These two genes are located at the 3' end of a predicted tailocin operon and have also been shown that they are oftentimes exchanged together, allowing for simplicity of complementation (Baltrus et al 2018).…”

Challenges of using protein antibiotics for pathogen control

“…In particular, the regulatory implications are far simpler and end users have the flexibility to decide where, when and what crops they wish to treat. Glasshouse experiments have demonstrated that phage‐like bacteriocins (tailocins) directly applied to tomato and tobacco are highly effective at protecting against important plant phytopathogenic bacteria 44,45 . Tailocins are multicomponent bacteriocins, making them difficult to produce in large‐scale in other model organisms 46 .…”

Prophylactic use of natural phage cocktail for plants and potential for human applications

“…2 A number of studies report the use of phages to treat specific plant pathogens. [3][4][5][6][7] These studies indicate a potential for prophylactic use of phages in plants.…”