Membrane vesicle engineering with "à la carte" bacterial-immunogenic molecules for organism-free plant vaccination.

The United Nations heralds a world population exponential increase exceeding 9.7 billion by 2050. This poses the challenge of covering the nutritional needs of an overpopulated world by the hand of preserving the environment. Extensive agriculture practices harnessed the employment of fertilizers and pesticides to boost crop productivity and prevent economic and harvest yield losses attributed to plagues and diseases. Unfortunately, the concomitant hazardous effects stemmed from such agriculture techniques are cumbersome, that is, biodiversity loss, soils and waters contaminations, and human and animal poisoning. Hence, the so-called 'green agriculture' research revolves around designing novel biopesticides and plant growth-promoting bio-agents to the end of curbing the detrimental effects. In this field, microbe-plant interactions studies offer multiple possibilities for reshaping the plant holobiont physiology to its benefit. Along these lines, bacterial extracellular membrane vesicles emerge as an appealing molecular tool to capitalize on. These nanoparticles convey a manifold of molecules that mediate intricate bacteria-plant interactions including plant immunomodulation. Herein, we bring into the spotlight bacterial extracellular membrane vesicle engineering to encase immunomodulatory effectors into their cargo for their application as biocontrol agents. The overarching goal is achieving plant priming by deploying its innate immune responses thereby preventing upcoming infections.