The foodborne pathogen L. monocytogenes is able to
resist stresses under different environmental conditions.
Recently, the release of MVs was observed in L. monocytogenes.
A mutant was analyzed to evaluate whether
the general stress transcription factor σB affected the production
of MVs. L. monocytogenes wild-type and sigB
mutant produced double membrane spheres ranging from
20 to 100 nm in diameter. Purified MVs were analyzed by
LC–ESI–MS/MS. A total of 130 proteins were identified
in MVs of the wild type and 18 proteins are known as σBdependent
proteins in L. monocytogenes. InIB and listeriolysin
O (LLO) were identified in MVs from the wild type
and also in the mutant; InIB is necessary for entry of L.
monocytogenes into host epithelial cells while LLO causes
vacuolar lysis