Simultaneous Discrimination of Cereulide-Producing Bacillus cereus and Psychrotolerant B. cereus Group by Matrix-Assisted Laser Desorption Ionization-Time-of-Flight Mass Spectrometry

• Published in: Journal of food protection Vol. 85; no. 8; pp. 1192 - 1202
• Main Authors: Takahashi, Naomi, Nagai, Satomi, Tomimatsu, Yumiko, Saito, Ayumi, Kaneta, Naoko, Tsujimoto, Yoshinori, Tamura, Hiroto
• Format: Journal Article
• Language: English
• Published: United States Elsevier Limited 01.08.2022
• Subjects: Bacillus cereus; Biomarkers; Cereulide; Chromatography; Depsipeptides - analysis; Depsipeptides - metabolism; Desorption; Food contamination & poisoning; Food industry; Food safety; Food spoilage; Foodborne diseases; Genes; Heat resistance; Illnesses; Ionization; Lasers; Manufacturers; Manufacturing; Mass spectrometry; Mass spectroscopy; Methods; Microorganisms; Milk; Morphology; Potassium; Proteins; Scientific imaging; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - methods; Spectroscopy; Spoilage; Vomiting; Japan; Bacillus weihenstephanensis; Matrix-assisted laser desorption ionization–time-of-flight mass spectrometry; Bacillus cereus; Bacillus cereus group; Bacillus mycoides; Cereulide
• ISSN: 0362-028X; 1944-9097
• DOI: 10.4315/JFP-21-450

Cereulide-producing Bacillus cereus, which causes foodborne illnesses with vomiting, and psychrotolerant B. cereus group strains such as Bacillus mycoides, which can grow at ≥7°C and cause spoilage of refrigerated foods, are significant concerns for the food industry. Rapid and simple methods to discriminate the cereulide-producing B. cereus and psychrotolerant B. cereus group strains from other B. cereus group strains are needed. We developed a novel, rapid, and simple method with matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) analysis for simultaneous discrimination of these two groups from other B. cereus group strains. A potassium adduct of cereulide was used to detect cereulide-producing B. cereus, and three ribosomal subunit proteins (L30, S16, and S20) were used to detect psychrotolerant B. cereus group. A total of 51 B. cereus group strains were analyzed by MALDI-TOF MS. The biomarkers allowed successful discrimination of 16 cereulide-producing B. cereus and 15 psychrotolerant B. cereus group strains from other B. cereus group strains. The results showed that this MALDI-TOF MS analysis allows simultaneous discrimination of cereulide-producing B. cereus and psychrotolerant B. cereus group strains from other B. cereus group strains. This efficient method has the potential to be a valuable tool for ensuring food safety.