Scientists Getting to the Core of Bacillus anthracis

Proteins have a notoriously difficult time traversing the hydrophobic layers of the plasma membrane. But some species, such as Bacillus anthracis, have devised clever ways to push their proteins through. Anthrax kills with a toxin, a compound composed of three proteins—protective antigen (PA), lethal factor (LF), and edema factor (EF)—that somehow penetrate the plasma membrane of the host cell and enter the cytosol where they make their kill. Antibiotics against anthrax attack the b

Leslie Pray
Jun 9, 2002
Proteins have a notoriously difficult time traversing the hydrophobic layers of the plasma membrane. But some species, such as Bacillus anthracis, have devised clever ways to push their proteins through. Anthrax kills with a toxin, a compound composed of three proteins—protective antigen (PA), lethal factor (LF), and edema factor (EF)—that somehow penetrate the plasma membrane of the host cell and enter the cytosol where they make their kill.

Antibiotics against anthrax attack the bacteria, not the deadly toxins that the bacteria secrete. If a patient does not receive antibiotics in the infection's early stage, he or she can die from accumulated toxin. But if antitoxin drugs were developed, they could be administered at this later stage of illness, and they could save lives.1

For years, scientists have been quietly working behind the scenes, trying to understand how anthrax toxins can penetrate the hydrophobic layers. While researchers do not...