Title |
Novosphingobium sp. PP1Y as a novel source of outer membrane vesicles |
Author |
Federica De Lise1, Francesca Mensitieri1, Giulia Rusciano2, Fabrizio Dal Piaz3, Giovanni Forte4, Flaviana Di Lorenzo5, Antonio Molinaro5, Armando Zarrelli5, Valeria Romanucci5, Valeria Cafaro1, Antonio Sasso2, Amelia Filippelli3, Alberto Di Donato1, and Viviana Izzo3* |
Address |
1Department of Biology, University of Naples, Federico II, Italy, 2Department of Physics, University of Naples, Federico II, Italy, 3Department of Medicine, Surgery and Dentistry, University of Salerno, Italy, 4Department of Pharmacy, University of Salerno, Italy, 5Department of Chemical Sciences, University of Naples Federico II, Italy |
Bibliography |
Journal of Microbiology, 57(6),498–508, 2019,
|
DOI |
10.1007/s12275-019-8483-2
|
Key Words |
outer membrane vesicles, exocytosis, bacterial
secretion, sphingomonadales, Novosphingobium, outer cell
membrane |
Abstract |
Outer membrane vesicles (OMVs) are nanostructures of 20–
200 nm diameter deriving from the surface of several Gramnegative
bacteria. OMVs are emerging as shuttles involved in
several mechanisms of communication and environmental
adaptation. In this work, OMVs were isolated and characterized
from Novosphingobium sp. PP1Y, a Gram-negative
non-pathogenic microorganism lacking LPS on the outer
membrane surface and whose genome was sequenced and
annotated. Scanning electron microscopy performed on samples
obtained from a culture in minimal medium highlighted
the presence of PP1Y cells embedded in an extracellular matrix
rich in vesicular structures. OMVs were collected from
the exhausted growth medium during the mid-exponential
phase, and purified by ultracentrifugation on a sucrose gradient.
Atomic force microscopy, dynamic light scattering and
nanoparticle tracking analysis showed that purified PP1Y
OMVs had a spherical morphology with a diameter of ca. 150
nm and were homogenous in size and shape. Moreover, proteomic
and fatty acid analysis of purified OMVs revealed a
specific biochemical “fingerprint”, suggesting interesting details
concerning their biogenesis and physiological role. Moreover,
these extracellular nanostructures do not appear to be
cytotoxic on HaCaT cell line, thus paving the way to their
future use as novel drug delivery systems. |