Delivery of Apoplastic Extracellular Vesicles Encapsulating Green-Synthesized Silver Nanoparticles to Treat Citrus Canker

Abstract

The citrus canker pathogen Xanthomonas axonopodis has caused severe damage to citrus crops worldwide, resulting in significant economic losses for the citrus industry. To address this, a green synthesis method was used to develop silver nanoparticles with the leaf extract of Phyllanthus niruri (GS-AgNP-LEPN). This method replaces the need for toxic reagents, as the LEPN acts as a reducing and capping agent. To further enhance their effectiveness, the GS-AgNP-LEPN were encapsulated in extracellular vesicles (EVs), nanovesicles with a diameter of approximately 30–1000 nm naturally released from different sources, including plant and mammalian cells, and found in the apoplastic fluid (APF) of leaves. When compared to a regular antibiotic (ampicillin), the delivery of APF-EV-GS-AgNP-LEPN and GS-AgNP-LEPN to X. axonopodis pv. was shown to have more significant antimicrobial activity. Our analysis showed the presence of phyllanthin and nirurinetin in the LEPN and found evidence that both could be responsible for antimicrobial activity against X. axonopodis pv. Ferredoxin-NADP+ reductase (FAD-FNR) and the effector protein XopAI play a crucial role in the survival and virulence of X. axonopodis pv. Our molecular docking studies showed that nirurinetin could bind to FAD-FNR and XopAI with high binding energies (−10.32 kcal/mol and −6.13 kcal/mol, respectively) as compared to phyllanthin (−6.42 kcal/mol and −2.93 kcal/mol, respectively), which was also supported by the western blot experiment. We conclude that (a) the hybrid of APF-EV and GS-NP could be an effective treatment for citrus canker, and (b) it works via the nirurinetin-dependent inhibition of FAD-FNR and XopAI in X. axonopodis pv.

Plant-Derived Exosome-Like Nanovesicles: Current Progress and Prospects

“…For instance, nanoparticles extracted and processed from leaves of P. niruri, termed Green-Synthesized Silver Nanoparticles (GS-AgNP-LEPN), when heated after being mixed with AgNO3 solution, have shown efficacy in treating citrus canker caused by Xanthomonas axonopodis. 140 These findings highlight the excellent research value and application potential of PELNs as drug carriers across multiple disciplines. However, the ability of PELNs to load and deliver drugs may be influenced by various factors, primarily encompassing the following aspects: Properties of PELNs: Different PELNs exhibit distinct characteristics, such as variations in size, charge, and stability.…”

In vitro mRNA‐S maternal vaccination induced altered immune regulation at the maternal‐fetal interface

“…21 Recent studies have demonstrated that EVs loaded with small molecules and proteins exert functional effects. [22][23][24] Similarly, we explored the functional consequences of EVs loaded with S proteins on decidual and chorion cell lines, integral components of the maternal-fetal interface. Our observations reveal distinct gene expression patterns of chemokines, cytokines, and toll-like receptors in maternal decidual and fetal chorion cells in response to maternal exposures.…”

Impact and Advances in the Role of Bacterial Extracellular Vesicles in Neurodegenerative Disease and Its Therapeutics

“…BEVs may be able to promote the ALP in different NDs, such as PD and AD [16,18,20]. Recent studies have shown that by controlling or promoting the ALP using BEVs, suggesting that BEVs could be a promising therapeutic target for treating NDs focusing on macroautophagy, chaperone-mediated autophagy, and microautophagy [46,53,61]. ALP is very important in removing toxic proteins, like alpha-synuclein in PD, Aβ, and phospho tau in AD, from building up in the brain and trying to clear this toxic proteins when activated.…”

“…BEVs may be able to promote the ALP in different NDs, such as PD and AD [16,18,20]. Recent studies have shown that by controlling or promoting the ALP using BEVs, suggesting that BEVs could be a promising therapeutic target for treating NDs focusing on macroautophagy, chaperone-mediated autophagy, and microautophagy [46,53,61].…”