In:
eLife, eLife Sciences Publications, Ltd, Vol. 7 ( 2018-07-16)
Abstract:
Some bacteria make toxins that punch large holes into the membranes of host cells, destroying them like a puncture destroys a football. These “pore-forming toxins” allow many bacterial species to infect a variety of organisms, from insects to humans. Some sophisticated pore-forming toxins, such as the anthrax toxin, do not only form a pore but also use it to flood lethal toxins into the cell to kill it. One bacterium called Xenorhabdus nematophila punctures the membranes of insect cells, using the same type of pore-forming toxins that other bacteria use to infect humans. Previous research has shown that two proteins – components A and B – form these pore-forming toxins. Given this two-protein formation, some scientists predicted these pore-forming toxins might act like those of the anthrax bacterium: one component forms the pore; the other component poisons the cell. But without detailed images of this pore-forming toxin’s structure, understanding exactly how these two components work together is almost impossible. To explore how components A and B operate within X. nematophila, Schubert et al. captured images of the molecular structure of the two proteins. Common methods reliant on X-rays and electron microscopes revealed the layouts of both components. By visualizing the proteins at different stages, Schubert et al. observed key structural changes that enable them to form the pore and puncture a host cell. Component A binds to component B’s back, forming a subunit – twelve to fifteen of which then conjoin as the pore-forming toxin. Schubert et al. conclude that component A stabilizes each subunit on the membrane and activates component B, which then punctures the membrane by swinging out its lower end. Unlike the anthrax pore-forming toxin, both components collaborate to form the pore complex and puncture the membrane. These results provide a foundation of knowledge about what these toxins look like and how they operate. More research building upon this structural analysis may help scientists develop antibiotics that prevent bacteria from destroying human cells.
Type of Medium:
Online Resource
ISSN:
2050-084X
DOI:
10.7554/eLife.38017.001
DOI:
10.7554/eLife.38017.002
DOI:
10.7554/eLife.38017.003
DOI:
10.7554/eLife.38017.004
DOI:
10.7554/eLife.38017.005
DOI:
10.7554/eLife.38017.006
DOI:
10.7554/eLife.38017.007
DOI:
10.7554/eLife.38017.008
DOI:
10.7554/eLife.38017.009
DOI:
10.7554/eLife.38017.010
DOI:
10.7554/eLife.38017.011
DOI:
10.7554/eLife.38017.012
DOI:
10.7554/eLife.38017.013
DOI:
10.7554/eLife.38017.014
DOI:
10.7554/eLife.38017.015
DOI:
10.7554/eLife.38017.016
DOI:
10.7554/eLife.38017.017
DOI:
10.7554/eLife.38017.018
DOI:
10.7554/eLife.38017.019
DOI:
10.7554/eLife.38017.020
DOI:
10.7554/eLife.38017.021
DOI:
10.7554/eLife.38017.022
DOI:
10.7554/eLife.38017.023
DOI:
10.7554/eLife.38017.024
DOI:
10.7554/eLife.38017.025
DOI:
10.7554/eLife.38017.026
DOI:
10.7554/eLife.38017.027
DOI:
10.7554/eLife.38017.028
DOI:
10.7554/eLife.38017.029
DOI:
10.7554/eLife.38017.030
DOI:
10.7554/eLife.38017.031
DOI:
10.7554/eLife.38017.032
DOI:
10.7554/eLife.38017.033
DOI:
10.7554/eLife.38017.034
DOI:
10.7554/eLife.38017.035
DOI:
10.7554/eLife.38017.043
DOI:
10.7554/eLife.38017.044
Language:
English
Publisher:
eLife Sciences Publications, Ltd
Publication Date:
2018
detail.hit.zdb_id:
2687154-3
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