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Abstract
Being able to track bacterial pathogens is essential for epidemiological purposes as well as monitoring in-house production facilities. Common bacterial pathogens, such as Salmonella serovars, are already been well defined, and their detection methods are very advanced. However, this will not be the case for emergent bacterial pathogens, as was the case for Cronobacter. The clinical significance of the organism is due to its association with rare sporadic infections in adults, and severe life-threatening outbreaks of necrotizing enterocolitis and meningitis in newborn babies. The main recognized route of infection being through the consumption of contaminated reconstituted powdered infant formula. Key to the advances in being able to track this organism during formula production and outbreaks in neonatal intensive care units has been the use of DNA sequence-based methods, and most recently those which profile whole-genome sequences. This chapter considers how the latest DNA sequence-based methods in genotyping Cronobacter serve as a model for analyzing emergent bacterial pathogens in the future. The methods considered will initially highlight the limitations of phenotyping, then advance from the DNA probe-based methods for serotyping through to DNA sequence-based methods, especially multilocus sequence typing which is supported by an open access database. Finally the development of typing methods based on whole-genomes sequences, CRISPR-cas array profiling and SNP analysis, will be covered. The overall perspective is that emergent pathogens need to be investigated with the most advanced methods in order for robust and reliable control measures to be adopted.
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Tang Y, Rasschaert G, Yu L, Chilton C, Baert L. Evaluation of Whole Genome Mapping as a Fast and Automated Molecular Epidemiological Tool for the Study of Cronobacter spp. in Powdered Infant Formula Processing Facilities. J Food Prot 2017; 80:1443-1450. [PMID: 28782998 DOI: 10.4315/0362-028x.jfp-17-029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Cronobacter has been identified as the causative agent of outbreaks or sporadic cases of meningitis, necrotizing enterocolitis, and septicemia associated with powdered infant formula. Food processing environments may provide a possible contamination route. The purpose of this study was to evaluate whole genome mapping (WGM) as a fast and automated molecular epidemiological method for characterizing Cronobacter spp. in the processing environment. This is the first study indicating the applicability of WGM to Cronobacter. WGM was compared with ribotyping, which is often used as an automated typing tool, and with pulsed-field gel electrophoresis, which is a well-known and highly discriminating tool that is also based on restriction site analysis. The comparison of the three tools was carried out on a subset of Cronobacter isolates collected from 2011 to 2014 through a monitoring program. The performance characteristics of WGM have not yet been described; therefore, in the current study its performance was evaluated based on five criteria: typeability, reproducibility, stability, epidemiological concordance, and the discrimination power. WGM was shown to produce typeable, reproducible, and stable results. With a similar cut-off of 98%, WGM was shown to have a discriminatory power equivalent to pulsed-field gel electrophoresis and higher than ribotyping. Future studies are needed to confirm the indicated cut-off level of 98%.
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Affiliation(s)
- Yanjie Tang
- 1 Nestlé Research Center, Nestec Ltd., Vers-Chez-les-Blanc, CH-1000 Lausanne 26, Switzerland; and
| | - Geertrui Rasschaert
- 2 Technology and Food Science Unit, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Brusselsesteenweg 370, 9090, Melle, Belgium
| | - Liping Yu
- 1 Nestlé Research Center, Nestec Ltd., Vers-Chez-les-Blanc, CH-1000 Lausanne 26, Switzerland; and
| | - Claire Chilton
- 1 Nestlé Research Center, Nestec Ltd., Vers-Chez-les-Blanc, CH-1000 Lausanne 26, Switzerland; and
| | - Leen Baert
- 1 Nestlé Research Center, Nestec Ltd., Vers-Chez-les-Blanc, CH-1000 Lausanne 26, Switzerland; and
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Vlach J, Javůrková B, Karamonová L, Blažková M, Fukal L. Novel PCR-RFLP system based on rpoB gene for differentiation of Cronobacter species. Food Microbiol 2016; 62:1-8. [PMID: 27889135 DOI: 10.1016/j.fm.2016.08.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 03/24/2016] [Accepted: 08/17/2016] [Indexed: 01/28/2023]
Abstract
Bacteria from the genus Cronobacter are opportunistic foodborne pathogens that can cause severe infections. More rapid, cost-effective and reliable methods are still required for the species identification of Cronobacter spp. In this study, we present a novel PCR-RFLP-based method that uses a newly designed pair of primers for the PCR-amplification of a partial rpoB gene sequence (1635 bp). The amplified products of DNA from 80 Cronobacter strains were separately digested with three restriction endonucleases (Csp6I, HinP1I, MboI). Using the obtained restriction patterns, a PCR-RFLP identification system was created to enable differentiation between all seven currently-known Cronobacter species. The functionality of our method was successfully verified on real food samples. Moreover, the relationships between the Cronobacter species were determined via a phylogenetic tree created from the RFLP patterns.
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Affiliation(s)
- Jiří Vlach
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, Technická 3, 166 28 Prague, Czech Republic
| | - Barbora Javůrková
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, Technická 3, 166 28 Prague, Czech Republic
| | - Ludmila Karamonová
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, Technická 3, 166 28 Prague, Czech Republic
| | - Martina Blažková
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, Technická 3, 166 28 Prague, Czech Republic.
| | - Ladislav Fukal
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, Technická 3, 166 28 Prague, Czech Republic
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4
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Chen W, Yang J, You C, Liu Z. Diversity of Cronobacter spp. isolates from the vegetables in the middle-east coastline of China. World J Microbiol Biotechnol 2016; 32:90. [PMID: 27116956 DOI: 10.1007/s11274-016-2033-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 02/14/2016] [Indexed: 11/30/2022]
Abstract
Cronobacter spp. has caused life-threatening neonatal infections mainly resulted from consumption of contaminated powdered infant formula. A total of 102 vegetable samples from retail markets were evaluated for the presence of Cronobacter spp. Thirty-five presumptive Cronobacter isolates were isolated and identified using API 20E and 16S rDNA sequencing analyses. All isolates and type strains were characterized using enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR), and genetic profiles of cluster analysis from this molecular typing test clearly showed that there were differences among isolates from different vegetables. A polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) based on the amplification of the gyrB gene (1258 bp) was developed to differentiate among Cronobacter species. A new PCR-RFLP assay based on the amplification of the gyrB gene using Alu I and Hinf I endonuclease combination is established and it has been confirmed an accurate and rapid subtyping method to differentiate Cronobacter species. Sequence analysis of the gyrB gene was proven to be suitable for the phylogenetic analysis of the Cronobacter strains, which has much better resolution based on SNPs in the identification of Cronobacter species specificity than PCR-RFLP and ERIC-PCR. Our study further confirmed that vegetables are one of the most common habitats or sources of Cronobacter spp. contamination in the middle-east coastline of China.
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Affiliation(s)
- Wanyi Chen
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Dairy Research Institute, Bright Dairy and Food Co., Ltd., Synergetic Innovation Center of Food Safety and Nutrition, 1518 West Jiangchang Rd., Shanghai, 200436, China
| | - Jielin Yang
- Shanghai Entry-Exit Inspection and Quarantine Bureau, 1208 Minsheng Rd., Shanghai, 200135, China
| | - Chunping You
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Dairy Research Institute, Bright Dairy and Food Co., Ltd., Synergetic Innovation Center of Food Safety and Nutrition, 1518 West Jiangchang Rd., Shanghai, 200436, China
| | - Zhenmin Liu
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Dairy Research Institute, Bright Dairy and Food Co., Ltd., Synergetic Innovation Center of Food Safety and Nutrition, 1518 West Jiangchang Rd., Shanghai, 200436, China.
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5
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Li Y, Chen Q, Jiang H, Jiao Y, Lu F, Bie X, Lu Z. Novel Development of a qPCR Assay Based on the rpoB Gene for Rapid Detection of Cronobacter spp. Curr Microbiol 2015; 72:436-43. [DOI: 10.1007/s00284-015-0971-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 11/16/2015] [Indexed: 11/28/2022]
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6
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Ye Y, Ling N, Han Y, Cao X, Wu Q. Detection of C
ronobacter
on glu
B
Gene and Differentiation of Four C
ronobacter
Species by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism Typing. J Food Saf 2015. [DOI: 10.1111/jfs.12192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yingwang Ye
- School of Biotechnology and Food Engineering; Hefei University of Technology; Hefei 230009 China
| | - Na Ling
- School of Biotechnology and Food Engineering; Hefei University of Technology; Hefei 230009 China
| | - Yongjia Han
- School of Biotechnology and Food Engineering; Hefei University of Technology; Hefei 230009 China
| | - Xiaodong Cao
- School of Biotechnology and Food Engineering; Hefei University of Technology; Hefei 230009 China
| | - Qingping Wu
- State Key Laboratory of Applied Microbiology; South China (The Ministry-Province Joint Development); Guangdong Provincial Key Laboratory of Microbiology Culture Collection and Application; Guangdong Institute of Microbiology; Guangzhou China
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Jackson EE, Sonbol H, Masood N, Forsythe SJ. Genotypic and phenotypic characteristics of Cronobacter species, with particular attention to the newly reclassified species Cronobacter helveticus, Cronobacter pulveris, and Cronobacter zurichensis. Food Microbiol 2014; 44:226-35. [PMID: 25084667 DOI: 10.1016/j.fm.2014.06.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 06/06/2014] [Accepted: 06/16/2014] [Indexed: 11/28/2022]
Abstract
In 2013, Enterobacter helveticus, Enterobacter pulveris and Enterobacter turicensis, were reclassified as Cronobacter helveticus, Cronobacter pulveris and Cronobacter zurichensis, respectively. Previously these species had been used as negative controls for some Cronobacter detection assays. This study examined cultural, biochemical and molecular Cronobacter detection and identification assays, with emphasis on the new species. Additionally, 32 Cronobacter genomes were examined for the presence of PCR target genes using the BLAST function of the online Cronobacter PubMLST facility. The results of the cultural methods varied and no single medium was able to correctly detect all Cronobacter spp. Since the supporting databases have not been updated to include the Cronobacter genus, Enterobacter sakazakii was returned for four strains of the newly reclassified species with ID32E and none with API 20E. PCR probes targeting rpoB and ompA could not correctly identify the new Cronobacter spp., due to primer specificity or absent target genes. As neonates have been identified as a high-risk group for infection, international standards require the absence of all Cronobacter species in powdered infant formula. However, many conventional detection methods cannot correctly identify the newly recognized species. Conversely, DNA sequence-based methods can adapt to taxonomic revisions and will likely become more common.
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Affiliation(s)
- E E Jackson
- Pathogen Research Group, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham, NG11 8NS, UK
| | - H Sonbol
- Pathogen Research Group, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham, NG11 8NS, UK
| | - N Masood
- Pathogen Research Group, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham, NG11 8NS, UK
| | - S J Forsythe
- Pathogen Research Group, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham, NG11 8NS, UK.
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8
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Li Y, Chen Q, Zhao J, Jiang H, Lu F, Bie X, Lu Z. Isolation, identification and antimicrobial resistance of Cronobacter spp. isolated from various foods in China. Food Control 2014. [DOI: 10.1016/j.foodcont.2013.09.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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9
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Ye Y, Li H, Wu Q, Zhang J, Lu Y. TheCronobactersp. in milk and dairy products: Detection and typing. INT J DAIRY TECHNOL 2014. [DOI: 10.1111/1471-0307.12111] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yingwang Ye
- School of Biotechnology and Food Engineering; Hefei University of Technology; Hefei 230009 China
- Guangdong Provincial Key Laboratory of Microbiology Culture Collection and Application; Guangdong Institute of Microbiology; Guangzhou 510070 China
| | - Hui Li
- School of Biotechnology and Food Engineering; Hefei University of Technology; Hefei 230009 China
- Guangdong Provincial Key Laboratory of Microbiology Culture Collection and Application; Guangdong Institute of Microbiology; Guangzhou 510070 China
| | - Qingping Wu
- Guangdong Provincial Key Laboratory of Microbiology Culture Collection and Application; Guangdong Institute of Microbiology; Guangzhou 510070 China
| | - Jumei Zhang
- Guangdong Provincial Key Laboratory of Microbiology Culture Collection and Application; Guangdong Institute of Microbiology; Guangzhou 510070 China
| | - Yudong Lu
- School of Biotechnology and Food Engineering; Hefei University of Technology; Hefei 230009 China
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Li Y, Cao L, Zhang C, Chen Q, Lu F, Bie X, Lu Z. Development and evaluation of a PCR-ELISA assay for the detection and quantification of Cronobacter spp. Int Dairy J 2013. [DOI: 10.1016/j.idairyj.2013.06.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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Chen W, Ai L, Yang J, Ren J, Li Y, Guo B. Molecular Typing of Cronobacter
Strains from Food in China by Enterobacterial Repetitive Intergenic Consensus Sequence PCR (ERIC-PCR) and Sequence Analysis of the gyrB
Gene. J Food Saf 2013. [DOI: 10.1111/jfs.12068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Wanyi Chen
- State Key Laboratory of Dairy Biotechnology; Technology Center of Bright Dairy & Food Co., Ltd; 1518 West Jiangchang Rd Shanghai 200436 China
| | - Lianzhong Ai
- State Key Laboratory of Dairy Biotechnology; Technology Center of Bright Dairy & Food Co., Ltd; 1518 West Jiangchang Rd Shanghai 200436 China
| | - Jielin Yang
- Shanghai Entry-Exit Inspection and Quarantine Bureau; Shanghai China
| | - Jing Ren
- State Key Laboratory of Dairy Biotechnology; Technology Center of Bright Dairy & Food Co., Ltd; 1518 West Jiangchang Rd Shanghai 200436 China
| | - Yunfei Li
- School of Agriculture and Biology; Shanghai Jiao Tong University; Shanghai China
| | - Benheng Guo
- State Key Laboratory of Dairy Biotechnology; Technology Center of Bright Dairy & Food Co., Ltd; 1518 West Jiangchang Rd Shanghai 200436 China
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12
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Cai XQ, Yu HQ, Ruan ZX, Yang LL, Bai JS, Qiu DY, Jian ZH, Xiao YQ, Yang JY, Le TH, Zhu XQ. Rapid detection and simultaneous genotyping of Cronobacter spp. (formerly Enterobacter sakazakii) in powdered infant formula using real-time PCR and high resolution melting (HRM) analysis. PLoS One 2013; 8:e67082. [PMID: 23825624 PMCID: PMC3692429 DOI: 10.1371/journal.pone.0067082] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 05/15/2013] [Indexed: 12/02/2022] Open
Abstract
Cronobacter spp. is an emerging pathogen that causes meningitis, sepsis, bacteremia, and necrotizing enterocolitis in neonates and children. The present study developed an assay integrating real-time PCR and high resolution melting (HRM) analysis targeting the OmpA gene for the specific detection and rapid identification of Cronobacter spp. (formerly Enterobacter sakazakii) in powdered infant formula. Eleven Cronobacter field isolates and 25 reference strains were examined using one pair of primers, having the accuracy of 100% in reference to conventional methods. The assay was proved to be highly sensitive with a detection limit of 102 CFU/ml without pre-enrichment, and highly concordant (100%) when compared with ISO-IDF 22964 in 89 actual samples. The method performed for Cronobacter spp. detection was less than 24 h, drastically shortened, compared to several days using standard culturing method, it is probe-free and reduces a risk of PCR carryover. Moreover, all Cronobacter strains examined in this study were genotyped into two species according to their HRM profiles. The established method should provide a molecular tool for direct detection and simultaneous genotyping of Cronobacter spp. in powdered infant formula.
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Affiliation(s)
- Xian-Quan Cai
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, People’s Republic of China
- Technical Center, Zhongshan Entry-Exit Inspection and Quarantine Bureau, Zhongshan, Guangdong Province, People’s Republic of China
| | - Hai-Qiong Yu
- Technical Center, Guangdong Entry-Exit Inspection and Quarantine Bureau, Guangzhou, Guangdong Province, People’s Republic of China
| | - Zhou-Xi Ruan
- Animal & Plant Inspection and Quarantine Technical Center, Shenzhen Entry-Exit Inspection and Quarantine Bureau, Shenzhen, Guangdong Province, People’s Republic of China
| | - Lei-Liang Yang
- Technical Center, Zhongshan Entry-Exit Inspection and Quarantine Bureau, Zhongshan, Guangdong Province, People’s Republic of China
| | - Jian-Shan Bai
- Guangzhou Airport Entry-Exit Inspection and Quarantine Bureau, Guangzhou, Guangdong Province, People’s Republic of China
| | - De-Yi Qiu
- Technical Center, Zhongshan Entry-Exit Inspection and Quarantine Bureau, Zhongshan, Guangdong Province, People’s Republic of China
| | - Zhi-Hua Jian
- Technical Center, Zhongshan Entry-Exit Inspection and Quarantine Bureau, Zhongshan, Guangdong Province, People’s Republic of China
| | - Yi-Qian Xiao
- Technical Center, Zhongshan Entry-Exit Inspection and Quarantine Bureau, Zhongshan, Guangdong Province, People’s Republic of China
| | - Jie-Yang Yang
- Technical Center, Zhongshan Entry-Exit Inspection and Quarantine Bureau, Zhongshan, Guangdong Province, People’s Republic of China
| | - Thanh Hoa Le
- Immunology Department, Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, People’s Republic of China
- * E-mail:
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13
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Grim CJ, Kotewicz ML, Power KA, Gopinath G, Franco AA, Jarvis KG, Yan QQ, Jackson SA, Sathyamoorthy V, Hu L, Pagotto F, Iversen C, Lehner A, Stephan R, Fanning S, Tall BD. Pan-genome analysis of the emerging foodborne pathogen Cronobacter spp. suggests a species-level bidirectional divergence driven by niche adaptation. BMC Genomics 2013; 14:366. [PMID: 23724777 PMCID: PMC3680222 DOI: 10.1186/1471-2164-14-366] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 05/24/2013] [Indexed: 11/24/2022] Open
Abstract
Background Members of the genus Cronobacter are causes of rare but severe illness in neonates and preterm infants following the ingestion of contaminated infant formula. Seven species have been described and two of the species genomes were subsequently published. In this study, we performed comparative genomics on eight strains of Cronobacter, including six that we sequenced (representing six of the seven species) and two previously published, closed genomes. Results We identified and characterized the features associated with the core and pan genome of the genus Cronobacter in an attempt to understand the evolution of these bacteria and the genetic content of each species. We identified 84 genomic regions that are present in two or more Cronobacter genomes, along with 45 unique genomic regions. Many potentially horizontally transferred genes, such as lysogenic prophages, were also identified. Most notable among these were several type six secretion system gene clusters, transposons that carried tellurium, copper and/or silver resistance genes, and a novel integrative conjugative element. Conclusions Cronobacter have diverged into two clusters, one consisting of C. dublinensis and C. muytjensii (Cdub-Cmuy) and the other comprised of C. sakazakii, C. malonaticus, C. universalis, and C. turicensis, (Csak-Cmal-Cuni-Ctur) from the most recent common ancestral species. While several genetic determinants for plant-association and human virulence could be found in the core genome of Cronobacter, the four Cdub-Cmuy clade genomes contained several accessory genomic regions important for survival in a plant-associated environmental niche, while the Csak-Cmal-Cuni-Ctur clade genomes harbored numerous virulence-related genetic traits.
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14
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Huang CH, Huang L. Differentiation of Cronobacter sakazakii and related taxa using direct sequencing, species-specific PCR, and mini-sequencing assays. Eur Food Res Technol 2012. [DOI: 10.1007/s00217-012-1884-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Species of Cronobacter – A review of recent advances in the genus and their significance in infant formula milk. Int Dairy J 2012. [DOI: 10.1016/j.idairyj.2012.06.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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16
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Huang CH, Chang MT, Huang L. Use of novel species-specific PCR primers targeted to DNA gyrase subunit B (gyrB) gene for species identification of the Cronobacter sakazakii and Cronobacter dublinensis. Mol Cell Probes 2012; 27:15-8. [PMID: 22963906 DOI: 10.1016/j.mcp.2012.08.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 08/07/2012] [Accepted: 08/10/2012] [Indexed: 11/18/2022]
Abstract
Cronobacter sakazakii and its phylogenetically closest species are considered to be an opportunistic pathogens associated with food-borne disease in neonates and infants. Neither phenotypic nor genotypic (16S ribosomal DNA sequence analysis) techniques can provide sufficient resolutions for accurately and rapidly identification of these species. The objective of this study was to develop species-specific PCR based on the gyrB gene sequence for direct species identification of the C. sakazakii and Cronobacter dublinensis within the C. sakazakii group. Two pair of species-specific primers were designed and used to specifically identify C. sakazakii and C. dublinensis, but none of the other C. sakazakii group strains. Our data indicate that the novel species-specific primers could be used to rapidly and accurately identify the species of C. sakazakii and C. dublinensis from C. sakazakii group by the PCR based assays.
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Affiliation(s)
- Chien-Hsun Huang
- Bioresource Collection and Research Center, Food Industry Research and Development Institute, 331 Shih-Pin Road, Hsinchu 30062, Taiwan, ROC
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17
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Use of rpoB gene sequence analysis for phylogenetic identification of Cronobacter species. J Microbiol Methods 2012; 88:316-8. [DOI: 10.1016/j.mimet.2011.12.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2011] [Revised: 12/02/2011] [Accepted: 12/04/2011] [Indexed: 11/30/2022]
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