Where and how do anthrax toxins exit endosomes to intoxicate host cells?
The role of Bacillus anthracis virulence factors in its pathogenesis has been subjected to intense investigation with the aim of finding novel preventive and therapeutic protocols. Toxins that are endocytosed and act in the cytosol of host cells have a central role in B. anthracis infection. Understanding of anthrax toxin cell entry has increased during the past few years and a composite picture is emerging. Nevertheless, unanswered and controversial questions remain, particularly concerning the site and mode of anthrax toxin cell entry, the role of anthrax toxin receptors in the process and the possible involvement of cytosolic chaperones, which might affect entry efficiency. Here, the current model of anthrax toxin cell entry, an alternative model and experimental approaches for clarifying unanswered questions will be discussed.
Puhar
Andrea
A
Dipartimento di Scienze Biomediche Sperimentali, Università di Padova, viale G. Colombo 3, I-35121 Padua, Italy. andrea.puhar@unipd.it
Montecucco
Cesare
C
D000818:Animals; D000881:Anthrax / Q000382:microbiology*; D000942:Antigens, Bacterial / Q000378:metabolism*; D001408:Bacillus anthracis / Q000472:pathogenicity*; D001427:Bacterial Toxins / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism*; D004705:Endocytosis; D011992:Endosomes / Q000378:metabolism*; D006801:Humans; D018832:Molecular Chaperones / Q000378:metabolism; D018000:Receptors, Peptide / Q000378:metabolism; D013171:Spores, Bacterial / Q000502:physiology
D000942:Antigens, Bacterial; D001427:Bacterial Toxins; D018832:Molecular Chaperones; D018000:Receptors, Peptide; C030325:anthrax toxin; C070309:anthrax toxin receptors