image: Botulinum neurotoxins (BoNTs), the causative agent of botulism, are produced by Clostridium botulinum together with several auxiliary proteins, including three hemagglutinins (HAs), as large multi-protein complexes. Shown here is the structure of a 12-subunit HA complex (the silver surface), which recognizes host adhesion protein E-cadherin (red ribbon, green spheres represent bound calcium atoms) and also binds to carbohydrates (red/yellow spheres) on the epithelial cell surface. By hijacking host receptors, the HA complex compromises the E-cadherin–mediated intercellular barrier to facilitate BoNT absorption during oral intoxication. Also shown is an immunofluorescence image of the human colorectal adenocarcinoma HT29 cells, where E-cadherin in the cell-cell junctions is green. This image relates to a paper that appeared in the 20 June, 2014, issue of Science, published by AAAS. The paper, by Kwangkook Lee at University of California, Irvine in Irvine, Calif., and colleagues was titled, 'Molecular basis for disruption of E-cadherin adhesion by botulinum neurotoxin A complex.' view more
Credit: [Credit: Rongsheng Jin, UC Irvine and Min Dong, Harvard Medical School]