Abstract
Listeria monocytogenes is an invasive bacterial pathogen capable of multiplying inside many host cells, including macrophages, enterocytes and hepatocytes. There is evidence to believe that secretion of listeriolysin O, an SH-activated exotoxin, is crucial for bacterial growth in host tissues. This exotoxin is stimulated in iron-deprived medium and mostly active at low pH (5.5). Electron microscopic studies showed that intracellular bacteria rapidly disrupt the vacuole membrane of phagosomes and freely multiply inside the cytosol of infected cells, thus escaping at an early stage of infection from the cellular microbicidal mechanisms. Vacuole disruption does not occur with a nonhemolytic mutant obtained by insertion of a single copy of transposon Tn1545 in the structural gene of listeriolysin O. These results strongly suggest that listeriolysin O is a major factor promoting intracellular growth of L. monocytogenes and that intracellular growth of virulent bacteria is initiated after escaping from the phagosomal compartment.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.