{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T10:39:15Z","timestamp":1790419155718,"version":"4.1.0"},"reference-count":59,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,11]],"date-time":"2022-01-11T00:00:00Z","timestamp":1641859200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"by Marie Sk\u0142odowska-Curie Innovative Training Network CLOSPORE","award":["642068"],"award-info":[{"award-number":["642068"]}]},{"name":"Doctoral Programme in Food Chain and Health","award":["Salaried position"],"award-info":[{"award-number":["Salaried position"]}]},{"DOI":"10.13039\/501100000781","name":"European Research Council","doi-asserted-by":"publisher","award":["683099"],"award-info":[{"award-number":["683099"]}],"id":[{"id":"10.13039\/501100000781","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Clostridium botulinum produces the botulinum neurotoxin that causes botulism, a rare but potentially lethal paralysis. Endospores play an important role in the survival, transmission, and pathogenesis of C. botulinum. C. botulinum strains are very diverse, both genetically and ecologically. Group I strains are terrestrial, mesophilic, and produce highly heat-resistant spores, while Group II strains can be terrestrial (type B) or aquatic (type E) and are generally psychrotrophic and produce spores of moderate heat resistance. Group III strains are either terrestrial or aquatic, mesophilic or slightly thermophilic, and the heat resistance properties of their spores are poorly characterized. Here, we analyzed the sporulation dynamics in population, spore morphology, and other spore properties of 10 C. botulinum strains belonging to Groups I\u2013III. We propose two distinct sporulation strategies used by C. botulinum Groups I\u2013III strains, report their spore properties, and suggest a putative role for the exosporium in conferring high heat resistance. Strains within each physiological group produced spores with similar characteristics, likely reflecting adaptation to respective environmental habitats. Our work provides new information on the spores and on the population and single-cell level strategies in the sporulation of C. botulinum.<\/jats:p>","DOI":"10.3390\/ijms23020754","type":"journal-article","created":{"date-parts":[[2022,1,11]],"date-time":"2022-01-11T14:05:07Z","timestamp":1641909907000},"page":"754","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Sporulation Strategies and Potential Role of the Exosporium in Survival and Persistence of Clostridium botulinum"],"prefix":"10.3390","volume":"23","author":[{"given":"In\u00eas M.","family":"Portinha","sequence":"first","affiliation":[{"name":"Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, P.O. Box 66, 00014 Helsinki, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fran\u00e7ois P.","family":"Douillard","sequence":"additional","affiliation":[{"name":"Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, P.O. Box 66, 00014 Helsinki, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hannu","family":"Korkeala","sequence":"additional","affiliation":[{"name":"Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, P.O. Box 66, 00014 Helsinki, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miia","family":"Lindstr\u00f6m","sequence":"additional","affiliation":[{"name":"Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, P.O. Box 66, 00014 Helsinki, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"298","DOI":"10.1128\/CMR.19.2.298-314.2006","article-title":"Laboratory diagnostics of botulism","volume":"19","author":"Korkeala","year":"2006","journal-title":"Clin. Microbiol. Rev."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Peck, M.W. (2009). Biology and genomic analysis of Clostridium botulinum. Adv. Microb. Physiol., 55.","DOI":"10.1016\/S0065-2911(09)05503-9"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"287","DOI":"10.3389\/fmicb.2014.00287","article-title":"Botulism outbreaks in natural environments\u2014An update","volume":"5","author":"Espelund","year":"2014","journal-title":"Front. 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