{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T16:21:42Z","timestamp":1791044502245,"version":"4.1.0"},"reference-count":50,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,2,11]],"date-time":"2022-02-11T00:00:00Z","timestamp":1644537600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>Clostridium botulinum produces botulinum neurotoxin (BoNT), which is the most toxic known protein and the causative agent of human botulism. BoNTs have similar structures and functions, comprising three functional domains: catalytic domain (L), translocation domain (HN), and receptor-binding domain (Hc). In the present study, BoNT\/E was selected as a model toxin to further explore the immunological significance of each domain. The EL-HN fragment (L and HN domains of BoNT\/E) retained the enzymatic activity without in vivo neurotoxicity. Extensive investigations showed EL-HN functional fragment had the highest protective efficacy and contained some functional neutralizing epitopes. Further experiments demonstrated the EL-HN provided a superior protective effect compared with the EHc or EHc and EL-HN combination. Thus, the EL-HN played an important role in immune protection against BoNT\/E and could provide an excellent platform for the design of botulinum vaccines and neutralizing antibodies. The EL-HN has the potential to replace EHc or toxoid as the optimal immunogen for the botulinum vaccine.<\/jats:p>","DOI":"10.3390\/toxins14020135","type":"journal-article","created":{"date-parts":[[2022,2,13]],"date-time":"2022-02-13T20:35:28Z","timestamp":1644784528000},"page":"135","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Functional EL-HN Fragment as a Potent Candidate Vaccine for the Prevention of Botulinum Neurotoxin Serotype E"],"prefix":"10.3390","volume":"14","author":[{"given":"Zhen","family":"Li","sequence":"first","affiliation":[{"name":"Beijing Institute of Biotechnology, Beijing 100071, China"},{"name":"Institute of Life Science and Biotechnology, Beijing Jiaotong University, Beijing 100044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiansheng","family":"Lu","sequence":"additional","affiliation":[{"name":"Beijing Institute of Biotechnology, Beijing 100071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiao","family":"Tan","sequence":"additional","affiliation":[{"name":"Beijing Institute of Biotechnology, Beijing 100071, China"},{"name":"Institute of Life Science and Biotechnology, Beijing Jiaotong University, Beijing 100044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rong","family":"Wang","sequence":"additional","affiliation":[{"name":"Beijing Institute of Biotechnology, Beijing 100071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9680-7356","authenticated-orcid":false,"given":"Qing","family":"Xu","sequence":"additional","affiliation":[{"name":"Institute of Life Science and Biotechnology, Beijing Jiaotong University, Beijing 100044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yunzhou","family":"Yu","sequence":"additional","affiliation":[{"name":"Beijing Institute of Biotechnology, Beijing 100071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhixin","family":"Yang","sequence":"additional","affiliation":[{"name":"Beijing Institute of Biotechnology, Beijing 100071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Rossetto, O., and Montecucco, C. 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