Characterization of the bacteriocins and the PrtR regulator in a plant-associated Pseudomonas strain

GODINO, AGUSTINA; FERNANDEZ, MARICRUZ; PRÍNCIPE, ANALÍA; VIVIANA LOPEZ RAMIREZ; JOSÉ MIGUEL QUESADA; VIRGINIA RIGO; MANUEL ESPINOSA-URGEL; GUSTAVO MORALES; FISCHER, SONIA

JOURNAL OF BIOTECHNOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2019

0168-1656

The emergence of antibiotic resistant bacterial strains demands the development of new antimicrobial agents. Inthe last decades, bacteriocins have gained significant interest due to their potential application as biopreservativesin the food industry and as therapeutic agents in medicine. Recent studies project the use of theseantimicrobials in agriculture as biocontrol agents. The characterization of bacteriocins and their genetic regulation,however, have been scarcely studied in plant-associated bacteria.In this report, an in-silico and proteomic analysis was performed to identify the bacteriocins produced byPseudomonas fluorescens SF4c. More than one functional bacteriocin was detected in this strain (S-type bacteriocinsand phage-tail-like bacteriocins [tailocins]). It is known that the regulator PrtR represses bacteriocinproduction in P. aeruginosa under normal condition. However, the mechanism for tailocin regulation remainsunknown in plant-associated pseudomonads. In this work, an orthologue of the prtR of P. aeruginosa wasidentified in the SF4c-tailocin cluster and a prtR null mutant constructed. The expression and production oftailocins was abolished in this mutant; thus evidencing that, unlike P. aeruginosa, PrtR is a positive regulator oftailocins expression in P. fluorescens.