RejuAgro A as an antimicrobial for fire blight control of pome fruits and beyond

Fire blight, caused by Erwinia amylovora, severely impacts global apple and pear production. Current control measures rely heavily on conventional antibiotics like streptomycin, oxytetracycline, and kasugamycin, which raise concerns regarding resistance development and environmental impacts. This research introduces RejuAgro A (RAA), an antimicrobial produced by Pseudomonas soli 0617-T307, showing potent activity against E. amylovora, including streptomycin-resistant strains. RAA demonstrates efficacy comparable to streptomycin in field trials, effectively reducing fire blight incidence. Studies on the antimicrobial mechanism reveal that RAA inhibits RNA, DNA, and protein synthesis, distinguishing from that of conventional antibiotics. Furthermore, RAA displays broad-spectrum activity against diverse plant bacterial and fungal pathogens. The RAA biosynthesis gene cluster in P. soli is identified, revealing key genes essential for its production. RAA presents an alternative to traditional antibiotics, potentially enhancing sustainable apple and pear production and addressing antibiotic resistance concerns.