Anthrax toxin, secreted by the anthrax bacterium, is made of proteins and toxic enzymes that bind together to inflict damage on a host organism. The inhibitor, which is described by the Rensselaer-Toronto team in the April 23 online edition of the journal Nature Biotechnology, works by preventing the assembly of toxic enzyme components, thereby blocking the formation of fully assembled anthrax toxin and neutralizing its activity.
The inhibitor protected rats from anthrax toxin in the study.
"Our eventual goal is to use the inhibitor as a human therapeutic for anthrax exposure, one that can stop the toxin from functioning inside the body," says Ravi Kane, the Merck Associate Professor of Chemical and Biological Engineering at Rensselaer and a principal investigator of the project. "Combining the inhibitor with antibiotic therapy may increase the likelihood of survival for an infected person."
The 2001 intentional release of anthrax spores via postal mail in the United States led to increased research on possible therapeutics and vaccines to treat toxins that could be used as biological weapons. The current treatment for anthrax exposure is antibiotics, but inhalation anthrax still has a fatality rate of 75 percent even after antibiotics are given, according to the Centers for Disease Control and Prevention. Antibiotics slow the progression of infection by targeting the bacteria, but do not counter the advanced destructive effects of anthrax toxin in the body.