Outer membrane vesicles of Lysobacter sp. XL1: biogenesis, functions, and applied prospects

Abstract

Outer membrane vesicles (OMVs) produced by Gram-negative bacteria have been intensively investigated in recent times. Vesicle formation models have been proposed, some factors affecting the process were established, and important roles vesicles play in vital activities of their producing cells were determined. Studies of pathogenic bacterial vesicles contribute to understanding the causes of acute infection and developing drugs on their basis. Despite intensive research, issues associated with the understanding of vesicle biogenesis, the mechanisms of bacterium-bacterium and pathogen-host interactions with participation of vesicles, still remain unresolved. This review discusses some results obtained in the research into OMVs of Lysobacter sp. XL1 VKM B-1576. This bacterium secretes into the environment a spectrum of bacteriolytic enzymes that hydrolyze peptidoglycan of competing bacteria, thus leading to their lysis. One of these enzymes, lytic endopeptidase L5, has been shown not only to be secreted by means of vesicles but also to be involved in their formation. As part of vesicles, the antimicrobial potential of L5 enzyme has been found to be considerably expanded. Vesicles have been shown to have a therapeutic effect in respect of anthrax infection and staphylococcal sepsis modelled in mice. The scientific basis for constructing liposomal antimicrobial preparations from vesicle phospholipids and recombinant bacteriolytic enzyme L5 has been formed.

Vesicular Delivery of the Antifungal Antibiotics of Lysobacter enzymogenes C3

“…The existence of extracellular bacterial vesicles has been known for some time (8). However, the identification of OMV as a potential part of the antifungal biocontrol activity of C3 fits a body of recent research elucidating the importance of OMV production as an extracellular mechanism of delivery of active molecules to host cells (14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26). Therefore, a role for OMV in the action of Lysobacter species fits an emerging paradigm in the field.…”

“…In particular, vesicle production has been previously documented in Lysobacter sp. strain XL1, showing the association of host-lytic enzymes with the vesicles (25,26). However, the production of OMV by the C3 biocontrol strain has not been previously investigated.…”

Regenerative therapy for the nonhealing cutaneous wounds

“…etc.) are known to produce a complex of bacteriolytic enzymes localized in the OMVs that are efficient against gram-positive pathogens [98,99]. Remarkably, there is no available information on the role of bacterial vesicles in tumorigenicity unlike exosomes, which appeared to impact the process.…”

Outer Membrane Vesicle-Mediated Codelivery of the Antifungal HSAF Metabolites and Lytic Polysaccharide Monooxygenase in the Predatory Lysobacter enzymogenes

“…In Lysobacter sp. XL1 and L. capsici VKM B-2533­(T), OMVs were found to contain bacteriolytic enzymes, which could lyse surrounding bacteria and enable the producer to gain advantage in competition. , …”

“…XL1 and L. capsici VKM B-2533(T), OMVs were found to contain bacteriolytic enzymes, which could lyse surrounding bacteria and enable the producer to gain advantage in competition. 28,29 Gram-negative bacteria are known to produce OMVs under certain circumstances, often as a response to stress. 30−32 As the vesicles bud from the outer membrane, cellular components encapsulated in OMVs, such as DNA, RNA, proteins, endotoxins, and virulence factors, are also delivered, which could mediate microbial interactions, pathogenesis, stress responses, and signaling.…”