{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:04:36Z","timestamp":1760058276924,"version":"build-2065373602"},"reference-count":28,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,3,22]],"date-time":"2025-03-22T00:00:00Z","timestamp":1742601600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Center for High Resolution Neutron Scattering","award":["DMR-2010792"],"award-info":[{"award-number":["DMR-2010792"]}]},{"name":"NIST Center for Neutron Research","award":["DMR-2010792"],"award-info":[{"award-number":["DMR-2010792"]}]},{"name":"National Institute of Standards and Technology USA","award":["DMR-2010792"],"award-info":[{"award-number":["DMR-2010792"]}]},{"name":"Marie Sk\u0142odowska-Curie\/Freiburg Institute of Advanced Studies (FRIAS) Senior Fellowship","award":["DMR-2010792"],"award-info":[{"award-number":["DMR-2010792"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>The bacterium Bacillus anthracis secretes three protein exotoxins: Protective Antigen 83 (PA83), Lethal Factor (LF), and Edema Factor (EF). A cleaved form of PA83 (PA63) aids LF and EF entry into the cytoplasm, which leads to anthrax-induced cell death. The Protein Data Bank (PDB) has more than 25 structures of LF: the monomer alone, bound with inhibitors, or bound to PA63. The structures are all\u2014with only minor shifts of a few \u00c5ngstr\u00f6ms\u2014nearly congruent. We have measured the structure of LF at equilibrium in D2O solution by small-angle neutron scattering (SANS). The shape is modeled well by a parallelepiped (all angles 90\u00b0) with dimensions of 12 \u00c5 \u00d7 49 \u00c5 \u00d7 129 \u00c5. For a protein with a typical density of 1.4, the molecular weight would be between 55 and 94 kDa, which is comparable to that of the 90.2 kDa monomer. However, the LF crystal structure PDB 1pwu (a generally V-shaped molecule with equal arm lengths \u2248 70 \u00c5) with the same model fits the dimensions 30 \u00c5 \u00d7 48 \u00c5 \u00d7 104 \u00c5. Given the large changes in the long and short dimensions, straightforward physical modeling of the solution structure from the crystal form is unable to match the SANS results.<\/jats:p>","DOI":"10.3390\/toxins17040157","type":"journal-article","created":{"date-parts":[[2025,3,24]],"date-time":"2025-03-24T04:48:18Z","timestamp":1742791698000},"page":"157","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Anthrax Toxin Lethal Factor in Solution Does Not Have the Protein\u2019s Crystallized Structure"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4712-0881","authenticated-orcid":false,"given":"Kenneth A.","family":"Rubinson","sequence":"first","affiliation":[{"name":"Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH 45435, USA"},{"name":"NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"John J.","family":"Kasianowicz","sequence":"additional","affiliation":[{"name":"Department of Physics, University of South Florida, Tampa, FL 33620, USA"},{"name":"Freiburg Institute for Advanced Studies, Universit\u00e4t Freiburg, 79104 Freiburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"756","DOI":"10.2105\/AJPH.92.5.756","article-title":"John Henry Bell: Occupational anthrax pioneer","volume":"92","author":"Fee","year":"2002","journal-title":"Am. 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