Anthrax-toxin component deciphered

 Images depict the molecular structure of edema factor, a component of the anthrax toxin. The X-ray diffraction models show the molecule before it enters a cell and once inside. The two bottom images show the opposite side of the molecule in each form. The twisted form inside cells interacts with a substance called calmodulin. Thus activated, edema factor spurs fluid overproduction, or edema, says researcher Andrew Bohm of the Boston Biomedical Research Institute in Watertown, Mass. Knowing the structure, described in the Jan. 24 Nature, may help scientists neutralize edema factor.