title: Multilocus variable-number of tandem repeat analysis (MLVA) for Clostridium tyrobutyricum strains isolated from cheese production environment.
abstract: Clostridium tyrobutyricum is a gram-positive spore-forming anaerobe that is considered as the main causative agent for late blowing in cheese due to butyric acid fermentation. In this study, multilocus variable-number of tandem repeat (VNTR) analysis (MLVA) for C. tyrobutyricum was developed to identify the source of contamination by C. tyrobutyricum spores in the cheese production environment. For each contig constructed from the results of a whole genome draft sequence of C. tyrobutyricum JCM11008(T) based on next-generation sequencing, VNTR loci that were effective for typing were searched using the Tandem Repeat Finder program. Five VNTR loci were amplified by polymerase chain reaction (PCR) to determine their number of repeats by sequencing, and MLVA was conducted. 25 strains of C. tyrobutyricum isolated from the environment, raw milk, and silage were classified into 18 MLVA types (DI=0.963). Of the C. tyrobutyricum strains isolated from raw milk, natural cheese, and blown processed cheese, strains with identical MLVA type were detected, which suggested that these strains might have shifted from natural cheese to blown processed cheese. MLVA could be an effective tool for monitoring contamination of natural cheese with C. tyrobutyricum in the processed cheese production environment because of its high discriminability, thereby allowing the analyst to trace the source of contamination.
authors.affiliation: Institute of Food Hygiene, Quality Assurance Department, Megmilk Snow Brand Co., Ltd., 1-1-2 Minamidai, Kawagoe-shi, Saitama 350-1165, Japan.
authors.forename: Masaharu
authors.initials: M
authors.lastname: Nishihara
authors.affiliation: Department of Food Science and Technology, Faculty of Marine Science, Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan. Electronic address: hajime@kaiyodai.ac.jp.
authors.forename: Hajime
authors.initials: H
authors.lastname: Takahashi
authors.affiliation: Institute of Food Hygiene, Quality Assurance Department, Megmilk Snow Brand Co., Ltd., 1-1-2 Minamidai, Kawagoe-shi, Saitama 350-1165, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Sudo
authors.affiliation: Department of Food Science and Technology, Faculty of Marine Science, Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kyoi
authors.affiliation: Department of Food Science and Technology, Faculty of Marine Science, Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Kawahara
authors.affiliation: Central Food Analysis Laboratory, Quality Assurance Department, Megmilk Snow Brand Co., Ltd., 1-1-2 Minamidai, Kawagoe-shi, Saitama 350-1165, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Ikeuchi
authors.affiliation: Institute of Food Hygiene, Quality Assurance Department, Megmilk Snow Brand Co., Ltd., 1-1-2 Minamidai, Kawagoe-shi, Saitama 350-1165, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Fujita
authors.affiliation: Department of Food Science and Technology, Faculty of Marine Science, Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kuda
authors.affiliation: Department of Food Science and Technology, Faculty of Marine Science, Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan.
authors.forename: Bon
authors.initials: B
authors.lastname: Kimura
authors.affiliation: Institute of Food Hygiene, Quality Assurance Department, Megmilk Snow Brand Co., Ltd., 1-1-2 Minamidai, Kawagoe-shi, Saitama 350-1165, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Yanahira
mesh_terms: D002611:Cheese / Q000382:microbiology*; D048014:Clostridium tyrobutyricum / Q000235:genetics* / Q000302:isolation & purification*; D005285:Fermentation; D005516:Food Microbiology / Q000379:methods*; D018598:Minisatellite Repeats / Q000235:genetics*; D016133:Polymerase Chain Reaction
keywords: Cheese; Clostridium tyrobutyricum; MLVA