2026-10-07T14:41:35Z https://api.figshare.com/v2/oai

oai:figshare.com:article/31316029 2026-09-29T15:48:03Z category_24352 category_24193 category_24250 category_24142 portal_753 item_type_1 month_year_09_2026

The production, cargo of extracellular vesicles in Dickeya dadantii 3937 and Pectobacterium brasiliense 1692 Lindokuhle Biyela (23173135) Silindile Maphosa (14626046) Lucy Moleleki (9190597) Bacteriology Genomics and transcriptomics Biological adaptation Cell metabolism Extracellular vesicles Dickeya dadantii Pectobacterium brasiliense DNA and RNA Chemical stress SDG 3 Good health and well-being <p dir="ltr">Soft Rot Pectobacteriaceae (SRP), comprising the genera Dickeya and Pectobacterium, are Gram-negative plant pathogens responsible for economically significant diseases such as soft rot and blackleg in potatoes. In South Africa, Pectobacterium brasiliense is the primary causal agent, while in parts of Europe, including France, Dickeya dadantii<i> </i>is particularly impactful. With no effective chemical control strategies currently available, a deeper understanding of their biology is essential for developing improved disease management approaches. This dissertation investigates the production and cargo of extracellular vesicles (EVs) in D. dadantii 3937 and P. brasiliense<i> </i>1692. EVs are membrane-bound structures involved in bacterial communication and virulence. A comprehensive literature review contextualises EV research in plant pathogenic bacteria, drawing insights from studies on human and animal pathogens to explore EV biogenesis, cargo, and plant interactions. Experimental analyses demonstrated that both species produce EVs with single and double membrane structures, consistent with outer membrane vesicles (OMVs) and outer–inner membrane vesicles (OIMVs). EV production increased during the stationary phase, and chemical stress altered vesicle yield and protein composition, particularly under ethanol and EDTA treatment. Molecular analyses confirmed that EVs carry DNA, RNA, and pectate lyases. Vesicle-associated nucleic acids included low-molecular-weight DNA and short RNAs, suggesting selective packaging and potential functional significance. Sequencing of DNA and RNA of EVs from P. brasiliense<i> </i>revealed that over half of its genes are represented within vesicular DNA, enriched in biosynthetic and catalytic functions. Distinct differences between externally associated and luminal RNA cargo were identified. As such, this work deepens our understanding of vesicle biology in SRP by characterising their production, structural features, and nucleic acid cargo composition.</p> 2026-09-29T15:48:03Z Image Figure 10.25403/UPresearchdata.31316029.v1 https://figshare.com/articles/figure/The_production_cargo_of_extracellular_vesicles_in_Dickeya_dadantii_3937_and_Pectobacterium_brasiliense_1692/31316029 CC BY 4.0