title: Molecular analysis of dominant species in Listeria monocytogenes-positive biofilms in the drains of food processing facilities.
abstract: Listeria monocytogenes exhibits symbiotic codependence with the dominant commensal bacteria, which may help it avoid being removed or inactivated by disinfectants in local environments. In this study, we investigated L. monocytogenes-positive biofilms at food production facilities, and the dominant bacterial species of the biofilms were identified to determine the properties of the microbiological background. For this purpose, the ISO 11290 method was used for the detection and isolation of L. monocytogenes, and the species were further identified based on 16S rRNA and hly genes. 16S rRNA gene-based cloning, terminal restriction fragment length polymorphism, and denaturing gradient gel electrophoresis were combined to evaluate the dominant bacteria of the drain biofilms. Out of 100 drain samples, 8 were naturally contaminated with L. monocytogenes. Three molecular methods consistently showed that Pseudomonas psychrophila, Pseudomonas sp., and Klebsiella oxytoca were dominant species in 3Q, 5Q, and 6Q samples; Aeromonas hydrophila and Klebsiella sp. were significantly dominant in 1-2, 1-3, and 3-2 samples; A. hydrophila and K. oxytoca were dominant in the 2-3 sample; and A. hydrophila and Pseudomonas sp. were prominent in the 3-3 sample. Different biofilms from the same plant shared common bands, suggesting that similar bacteria can be found and can be dominant in different biofilms. This study provides a better understanding of the dominant compositions in these bacterial communities. Further studies to determine the mechanism of co-culture with L. monocytogenes will be of critical importance in predicting effective disinfection strategies.
authors.affiliation: Department Biological Engineering, Guangdong University of Technology, Guangzhou Higher Education Mega Center 100, Guangzhou, 510006, China. yelasis@163.com.
authors.forename: Yanlan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department Biological Engineering, Guangdong University of Technology, Guangzhou Higher Education Mega Center 100, Guangzhou, 510006, China. hmzhang@gdut.edu.cn.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department Biological Engineering, Guangdong University of Technology, Guangzhou Higher Education Mega Center 100, Guangzhou, 510006, China. 13580475663@163.com.
authors.forename: Changli
authors.initials: C
authors.lastname: Wu
authors.affiliation: Department Biological Engineering, Guangdong University of Technology, Guangzhou Higher Education Mega Center 100, Guangzhou, 510006, China. 18319641084@163.com.
authors.forename: Wenjia
authors.initials: W
authors.lastname: Deng
authors.affiliation: Department Biological Engineering, Guangdong University of Technology, Guangzhou Higher Education Mega Center 100, Guangzhou, 510006, China. 15290718891@163.com.
authors.forename: Dong
authors.initials: D
authors.lastname: Wang
authors.affiliation: Department Biological Engineering, Guangdong University of Technology, Guangzhou Higher Education Mega Center 100, Guangzhou, 510006, China. 13660109650@163.com.
authors.forename: Guifen
authors.initials: G
authors.lastname: Zhao
authors.affiliation: Department Biological Engineering, Guangdong University of Technology, Guangzhou Higher Education Mega Center 100, Guangzhou, 510006, China. 13611428061@163.com.
authors.forename: Jiankun
authors.initials: J
authors.lastname: Song
authors.affiliation: Department Biological Engineering, Guangdong University of Technology, Guangzhou Higher Education Mega Center 100, Guangzhou, 510006, China. cljy@163.com.
authors.forename: Yan
authors.initials: Y
authors.lastname: Jiang
mesh_terms: D016980:Aeromonas hydrophila / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D018441:Biofilms / Q000254:growth & development*; D003001:Cloning, Molecular; D005511:Food Handling; D015870:Gene Expression; D006459:Hemolysin Factors / Q000235:genetics / Q000378:metabolism; D006801:Humans; D041121:Klebsiella oxytoca / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D008089:Listeria monocytogenes / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D059013:Microbial Consortia / Q000235:genetics; D011549:Pseudomonas / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D012336:RNA, Ribosomal, 16S / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D013559:Symbiosis / Q000235:genetics; D062065:Wastewater / Q000382:microbiology
chemical_list: D012336:RNA, Ribosomal, 16S; D011994:Recombinant Proteins; D062065:Wastewater
keywords: Biofilm; Cloning; DGGE; Disinfection; L. monocytogenes; T-RFLP