{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T02:52:47Z","timestamp":1790304767073,"version":"4.1.0"},"reference-count":28,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2019,2,9]],"date-time":"2019-02-09T00:00:00Z","timestamp":1549670400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"food, nutrition and health platform of the University of Applied Sciences of Western Switzerland, HES-SO","award":["grants no. 39\u2019244 and no. 42\u2019336"],"award-info":[{"award-number":["grants no. 39\u2019244 and no. 42\u2019336"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>Routine identification of pathogens by MALDI-TOF MS (matrix-assisted laser desorption ionisation time-of-flight mass spectrometry) is based on the fingerprint of intracellular proteins. This work evaluated the use of MALDI-TOF MS for the identification of extracellular pathogen factors. A Staphylococcus aureus isolate from a food contaminant was exponentially grown in liquid cultures. Secreted proteins were collected using methanol\u2013 chloroform precipitation and analysed by MALDI-TOF MS. A main peak m\/z 28,250 was demonstrated, which was identified as S.aureus enterotoxin type B (SEB) by using the pure authentic SEB reference of 28.2 kDa and by amino acid sequence analysis. SEB was also detected in this intact form following pasteurization and cooking treatments. Further application of the elaborated MALDI-TOF MS protocol resulted in the detection of SEA at m\/z 27,032 and SEC at m\/z 27,629. In conclusion, a simple sample preparation from S.aureus cultures and an easy-to-perform identification of pathogen factors SE in intact form represents a promising next-generation application of MALDI-TOF MS.<\/jats:p>","DOI":"10.3390\/toxins11020101","type":"journal-article","created":{"date-parts":[[2019,2,12]],"date-time":"2019-02-12T03:18:20Z","timestamp":1549941500000},"page":"101","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Intact Staphylococcus Enterotoxin SEB from Culture Supernatant Detected by MALDI-TOF Mass Spectrometry"],"prefix":"10.3390","volume":"11","author":[{"given":"Jenna","family":"Tonacini","sequence":"first","affiliation":[{"name":"Institute of Life Technologies, University of Applied Sciences, HES-SO Valais\/Wallis, Sion 1950, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dario","family":"Stephan","sequence":"additional","affiliation":[{"name":"Institute of Life Technologies, University of Applied Sciences, HES-SO Valais\/Wallis, Sion 1950, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guido","family":"Vogel","sequence":"additional","affiliation":[{"name":"Mabritec AG, Food Technology, Riehen 4125, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marc-Andr\u00e9","family":"Avondet","sequence":"additional","affiliation":[{"name":"Spiez Laboratory, Federal Office for Civil Protection, Spiez 3700, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Franka","family":"Kalman","sequence":"additional","affiliation":[{"name":"Institute of Life Technologies, University of Applied Sciences, HES-SO Valais\/Wallis, Sion 1950, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julien","family":"Crovadore","sequence":"additional","affiliation":[{"name":"Plants and Pathogens Group, Research Institute Land Nature Environment School of, Architecture and Landscape HEPIA HES-SO University of Applied Sciences and Arts Western Switzerland, 150 route de Presinge, 1254 Geneva\/Jussy, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9977-9952","authenticated-orcid":false,"given":"Fran\u00e7ois","family":"Lefort","sequence":"additional","affiliation":[{"name":"Plants and Pathogens Group, Research Institute Land Nature Environment School of, Architecture and Landscape HEPIA HES-SO University of Applied Sciences and Arts Western Switzerland, 150 route de Presinge, 1254 Geneva\/Jussy, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bruno","family":"Schnyder","sequence":"additional","affiliation":[{"name":"Institute of Life Technologies, University of Applied Sciences, HES-SO Valais\/Wallis, Sion 1950, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"815","DOI":"10.1111\/j.1574-6976.2011.00311.x","article-title":"Staphylococcus aureus and its food poisoning toxins: Characterization and outbreak investigation","volume":"36","author":"Hennekinne","year":"2012","journal-title":"FEMS Microbiol. 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