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Kim HR, Joe C, Hwang ET, Gu MB, Kim BC. Group selective aptamers: Broad-spectrum recognition of target groups in Cronobacter species and implementation of electrochemical biosensors as receptors. Biosens Bioelectron 2024; 246:115843. [PMID: 38006700 DOI: 10.1016/j.bios.2023.115843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 11/02/2023] [Accepted: 11/14/2023] [Indexed: 11/27/2023]
Abstract
Aptamers are a versatile class of receptors with a high affinity and selectivity for specific targets. Although their ability to recognize individual targets has been extensively studied, some scenarios require the development of receptors capable of identifying all target groups. This study investigated the use of aptamers to achieve the broad-spectrum recognition of groups instead of individual targets. Aptamers were screened for selectively distinct groups of Cronobacter species associated with foodborne diseases. Seven Cronobacter spp. were divided into Group A (C. sakazakii, C. malonaticus, C. turicensis, and C. muytjensii) and Group B (C. dublinensis, C. condimenti, and C. universalis). Aptamers with exclusive selectivity for each group were identified, allowing binding to the species within their designated group while excluding those from the other group. The screened aptamers demonstrated reliable affinity and specificity with dissociation constants ranging from 1.3 to 399.7 nM for Group A and 4.0-24.5 nM for Group B. These aptamers have also been successfully employed as receptors in an electrochemical biosensor platform, enabling the selective detection of each group based on the corresponding aptamer (limit of detection was 7.8 and 3.2 CFU for Group A and Group B, respectively). The electrochemical sensor effectively detected the extent of infection in each group in powdered infant formula samples. This study highlights the successful screening and application of group-selective aptamers as sensing receptors, emphasizing their potential for diverse applications in different fields such as food safety, environmental monitoring, and clinical diagnostics, where the selective biosensing of target groups is crucial.
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Affiliation(s)
- Hye Ri Kim
- Center for Sustainable Environment Research, Korea Institute of Science and Technology (KIST), Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Cheulmin Joe
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - Ee Taek Hwang
- Department of Food Biotechnology, Dong-A University, Busan, Republic of Korea
| | - Man Bock Gu
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea.
| | - Byoung Chan Kim
- Center for Sustainable Environment Research, Korea Institute of Science and Technology (KIST), Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea; Division of Energy and Environment Technology, KIST School, University of Science and Technology (UST), Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea.
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2
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Jaradat ZW, Al-Mousa WA, Elbetieha AM, Ababneh QO, Al-Nabulsi AA, Jang H, Gangiredla J, Patel IR, Gopinath GR, Tall BD. Virulence, antimicrobial susceptibility, and phylogenetic analysis of Cronobacter sakazakii isolates of food origins from Jordan. J Appl Microbiol 2022; 133:2528-2546. [PMID: 35858752 DOI: 10.1111/jam.15723] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 07/14/2022] [Accepted: 07/15/2022] [Indexed: 11/26/2022]
Abstract
AIMS to characterize a collection of Cronobacter sakazakii isolates collected from various origins in Jordan. METHODS AND RESULTS the isolates were characterized using 16S rRNA sequencing, DNA microarray, multi-locus sequence typing (MLST), O-serotyping, virulence gene identification, and antibiotic susceptibility testing. The identities and phylogenetic relatedness revealed that C. sakazakii sequence type 4 (ST4) and Csak O:1 serotype was the most prevalent STs and serovars among these C. sakazakii strains. PCR screening of putative virulence genes showed that the siderophore-interacting protein gene (sip) and iron acquisition gene clusters (eitCBAD and iucABCD/iutA) were the most detected genes with noticeable variability in the type 6 secretion system (T6SS) and filamentous hemagglutinin/adhesion (FHA) gene loci. The antibiotic resistance profiles revealed that the majority of the isolates were susceptible to all antibiotics used despite harboring a class C β-lactamase resistance gene. CONCLUSIONS the results described in this report provide additional insights about the considerable genotypic and phenotypic heterogeneity within C. sakazakii. SIGNIFICANCE AND IMPACT OF THE STUDY the information reported in this study might be of great value in understanding the origins of C. sakazakii isolates, in addition to their diversity and variability, which might be helpful in preventing future outbreaks of this pathogen.
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Affiliation(s)
- Ziad W Jaradat
- Department of Biotechnology and Genetic Engineering, Jordan University of Science and Technology, Irbid, P. O Box 3030, 22110, Jordan
| | - Waseem A Al-Mousa
- Department of Biotechnology and Genetic Engineering, Jordan University of Science and Technology, Irbid, P. O Box 3030, 22110, Jordan
| | - Ahmed M Elbetieha
- Department of Biotechnology and Genetic Engineering, Jordan University of Science and Technology, Irbid, P. O Box 3030, 22110, Jordan
| | - Qutaiba O Ababneh
- Department of Biotechnology and Genetic Engineering, Jordan University of Science and Technology, Irbid, P. O Box 3030, 22110, Jordan
| | - Anas A Al-Nabulsi
- Department of Nutrition and Food Technology, Jordan University of Science and Technology, P. O Box 3030, 22110, Irbid, Jordan
| | - Hyein Jang
- US Food and Drug Administration, Center for Food Safety and Applied Nutrition, 20708, Laurel, MD
| | - Jayanthi Gangiredla
- US Food and Drug Administration, Center for Food Safety and Applied Nutrition, 20708, Laurel, MD
| | - Isha R Patel
- US Food and Drug Administration, Center for Food Safety and Applied Nutrition, 20708, Laurel, MD
| | - Gopal R Gopinath
- US Food and Drug Administration, Center for Food Safety and Applied Nutrition, 20708, Laurel, MD
| | - Ben D Tall
- US Food and Drug Administration, Center for Food Safety and Applied Nutrition, 20708, Laurel, MD
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3
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Bai S, Zhang P, Zhang C, Du J, Du X, Zhu C, Liu J, Xie P, Li S. Comparative Study of the Gut Microbiota Among Four Different Marine Mammals in an Aquarium. Front Microbiol 2021; 12:769012. [PMID: 34745077 PMCID: PMC8567075 DOI: 10.3389/fmicb.2021.769012] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 09/23/2021] [Indexed: 12/18/2022] Open
Abstract
Despite an increasing appreciation in the importance of host–microbe interactions in ecological and evolutionary processes, information on the gut microbial communities of some marine mammals is still lacking. Moreover, whether diet, environment, or host phylogeny has the greatest impact on microbial community structure is still unknown. To fill part of this knowledge gap, we exploited a natural experiment provided by an aquarium with belugas (Delphinapterus leucas) affiliated with family Monodontidae, Pacific white-sided dolphins (Lagenorhynchus obliquidens) and common bottlenose dolphin (Tursiops truncatus) affiliated with family Delphinidae, and Cape fur seals (Arctocephalus pusillus pusillus) affiliated with family Otariidae. Results show significant differences in microbial community composition of whales, dolphins, and fur seals and indicate that host phylogeny (family level) plays the most important role in shaping the microbial communities, rather than food and environment. In general, the gut microbial communities of dolphins had significantly lower diversity compared to that of whales and fur seals. Overall, the gut microbial communities were mainly composed of Firmicutes and Gammaproteobacteria, together with some from Bacteroidetes, Fusobacteria, and Epsilonbacteraeota. However, specific bacterial lineages were differentially distributed among the marine mammal groups. For instance, Lachnospiraceae, Ruminococcaceae, and Peptostreptococcaceae were the dominant bacterial lineages in the gut of belugas, while for Cape fur seals, Moraxellaceae and Bacteroidaceae were the main bacterial lineages. Moreover, gut microbial communities in both Pacific white-sided dolphins and common bottlenose dolphins were dominated by a number of pathogenic bacteria, including Clostridium perfringens, Vibrio fluvialis, and Morganella morganii, reflecting the poor health condition of these animals. Although there is a growing recognition of the role microorganisms play in the gut of marine mammals, current knowledge about these microbial communities is still severely lacking. Large-scale research studies should be undertaken to reveal the roles played by the gut microbiota of different marine mammal species.
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Affiliation(s)
- Shijie Bai
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | - Peijun Zhang
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | | | - Jiang Du
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Medical University, Haikou, China
| | | | - Chengwei Zhu
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | - Jun Liu
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Peiyu Xie
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Songhai Li
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
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4
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Costa PV, de Siqueira RM, Rosa Guimarães AC, Vasconcellos L, Midlej V, Silva da Conceição GM, Forsythe SJ, Lima Brandão ML. Cytotoxicity profile of Cronobacter species isolated from food and clinical specimens in Brazil. J Appl Microbiol 2020; 130:1758-1769. [PMID: 33090617 DOI: 10.1111/jam.14890] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 09/26/2020] [Accepted: 10/04/2020] [Indexed: 12/31/2022]
Abstract
AIMS The objective of this study was to evaluate the cytotoxic activity of Cronobacter strains isolated from foods (n = 50) and clinical samples (n = 6) in Brazil and genotype selected strains (n = 18) using multi-locus sequence typing (MLST) METHODS AND RESULTS: The cytotoxic activity of C. sakazakii (n = 29), C. dublinensis (n = 13), C. malonaticus (n = 6), C. turicensis (n = 6) and C. muytjensii (n = 2) was screened using Vero, RK13, Hep2c, NCTC clone 929 and BHK-21 cell lines. Selected Cronobacter strains were assigned to C. sakazakii ST 21, C. turicensis ST 252, C. sakazakii ST 647, and three newly assigned STs: C. turicensis STs 738-740. The maximum death caused by non-heat-treated filtrates was 20·4, 86·2, 47·0 and 84·0%, in Vero, RK13, Hep2c and NCTC clone 929 cells, respectively. These were caused by C. sakazakii strains C291 and C292 (ST 494) which had been isolated during neonatal Cronobacter meningitis infection, and C110 (ST 395) isolated from flaxseed flour. Thermal treatment (100°C/20 min) significantly reduced the cytotoxicity activity in NCTC clone 929 and Vero cells (P ≤ 2 × 10-6 ), but not in RK13 (P = 0·12) and Hep2c (P = 0·85), indicating the cytotoxin(s) were probably proteinaceous. Electron microscopy revealed that cytotoxic compounds from C. sakazakii induced several cell death characteristics, including loss of cell-cell contact, microvilli reduction and cellular lysis. Autophagic vacuoles and mitochondrial damage were the most common ultrastructural features observed. CONCLUSIONS It was concluded that Cronobacter strains, especially C. sakazakii, could produce heat-labile cytotoxic compounds in cell filtrates. SIGNIFICANCE AND IMPACT OF THE STUDY This study providing insights into the pathogenesis of the Cronobacter genus. Cytotoxins were identified in excreted filtrates of C. sakazakii strains isolated from food and clinical specimens. The presence of Cronobacter strains that can produce cytotoxins in foods can be a potential threat to human health and highlight the need for high levels of hygiene.
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Affiliation(s)
- P V Costa
- Laboratory of Microbiology of Food and Sanitizes, INCQS/Fiocruz, Rio de Janeiro, Brazil
| | - R M de Siqueira
- Laboratory of Viral Vaccines, Biopharmaceutics, and Cell Culture, INCQS/Fiocruz, Rio de Janeiro, Brazil
| | - A C Rosa Guimarães
- Laboratory of Viral Vaccines, Biopharmaceutics, and Cell Culture, INCQS/Fiocruz, Rio de Janeiro, Brazil
| | - L Vasconcellos
- Laboratory of Microbiology of Food and Sanitizes, INCQS/Fiocruz, Rio de Janeiro, Brazil
| | - V Midlej
- Laboratory of Cellular Ultrastructure, IOC/Fiocruz, Rio de Janeiro, Brazil
| | | | - S J Forsythe
- Foodmicrobe.com, Adams Hill, Keyworth, Nottinghamshire, UK
| | - M L Lima Brandão
- Laboratory of Microbiology Control, Biomanguinhos/Fiocruz, Rio de Janeiro, Brazil
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5
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Jang H, Chase HR, Gangiredla J, Grim CJ, Patel IR, Kothary MH, Jackson SA, Mammel MK, Carter L, Negrete F, Finkelstein S, Weinstein L, Yan Q, Iversen C, Pagotto F, Stephan R, Lehner A, Eshwar AK, Fanning S, Farber J, Gopinath GR, Tall BD, Pava-Ripoll M. Analysis of the Molecular Diversity Among Cronobacter Species Isolated From Filth Flies Using Targeted PCR, Pan Genomic DNA Microarray, and Whole Genome Sequencing Analyses. Front Microbiol 2020; 11:561204. [PMID: 33101235 PMCID: PMC7545074 DOI: 10.3389/fmicb.2020.561204] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 09/03/2020] [Indexed: 11/17/2022] Open
Abstract
Cronobacter species are opportunistic pathogens capable of causing life-threatening infections in humans, with serious complications arising in neonates, infants, immuno-compromised individuals, and elderly adults. The genus is comprised of seven species: Cronobacter sakazakii, Cronobacter malonaticus, Cronobacter turicensis, Cronobacter muytjensii, Cronobacter dublinensis, Cronobacter universalis, and Cronobacter condimenti. Despite a multiplicity of genomic data for the genus, little is known about likely transmission vectors. Using DNA microarray analysis, in parallel with whole genome sequencing, and targeted PCR analyses, the total gene content of two C. malonaticus, three C. turicensis, and 14 C. sakazaki isolated from various filth flies was assessed. Phylogenetic relatedness among these and other strains obtained during surveillance and outbreak investigations were comparatively assessed. Specifically, microarray analysis (MA) demonstrated its utility to cluster strains according to species-specific and sequence type (ST) phylogenetic relatedness, and that the fly strains clustered among strains obtained from clinical, food and environmental sources from United States, Europe, and Southeast Asia. This combinatorial approach was useful in data mining for virulence factor genes, and phage genes and gene clusters. In addition, results of plasmidotyping were in agreement with the species identity for each strain as determined by species-specific PCR assays, MA, and whole genome sequencing. Microarray and BLAST analyses of Cronobacter fly sequence datasets were corroborative and showed that the presence and absence of virulence factors followed species and ST evolutionary lines even though such genes were orthologous. Additionally, zebrafish infectivity studies showed that these pathotypes were as virulent to zebrafish embryos as other clinical strains. In summary, these findings support a striking phylogeny amongst fly, clinical, and surveillance strains isolated during 2010–2015, suggesting that flies are capable vectors for transmission of virulent Cronobacter spp.; they continue to circulate among United States and European populations, environments, and that this “pattern of circulation” has continued over decades.
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Affiliation(s)
- Hyein Jang
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Hannah R Chase
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Jayanthi Gangiredla
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Christopher J Grim
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Isha R Patel
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Mahendra H Kothary
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Scott A Jackson
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Mark K Mammel
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Laurenda Carter
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Flavia Negrete
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Samantha Finkelstein
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Leah Weinstein
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - QiongQiong Yan
- WHO Collaborating Centre for Cronobacter, University College Dublin, Dublin, Ireland.,UCD Centre for Food Safety, School of Public Health, Physiotherapy and Population Science, University College Dublin, Dublin, Ireland
| | - Carol Iversen
- WHO Collaborating Centre for Cronobacter, University College Dublin, Dublin, Ireland.,UCD Centre for Food Safety, School of Public Health, Physiotherapy and Population Science, University College Dublin, Dublin, Ireland
| | - Franco Pagotto
- Food Directorate, Bureau of Microbial Hazards, Health Canada, Ottawa, ON, Canada
| | - Roger Stephan
- Institute for Food Safety and Hygiene, University of Zürich, Zurich, Switzerland
| | - Angelika Lehner
- Institute for Food Safety and Hygiene, University of Zürich, Zurich, Switzerland
| | - Athmanya K Eshwar
- Institute for Food Safety and Hygiene, University of Zürich, Zurich, Switzerland
| | - Seamus Fanning
- WHO Collaborating Centre for Cronobacter, University College Dublin, Dublin, Ireland.,UCD Centre for Food Safety, School of Public Health, Physiotherapy and Population Science, University College Dublin, Dublin, Ireland
| | - Jeffery Farber
- Department of Food Science, University of Guelph, Guelph, ON, Canada
| | - Gopal R Gopinath
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Ben D Tall
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, United States
| | - Monica Pava-Ripoll
- Center of Food Safety and Applied Nutrition, U. S. Food & Drug Administration, College Park, MD, United States
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6
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Rossi A, Fisher MA. Characterization of six clinical isolates of Chimaeribacter gen. nov., a novel genus related to the Yersiniaceae family and the three species Chimaeribacter arupi sp. nov., Chimaeribacter coloradensis sp. nov , and Chimaeribacter californicus sp. nov. Int J Syst Evol Microbiol 2020; 70:2703-2712. [PMID: 32141808 DOI: 10.1099/ijsem.0.004094] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Eight genetically related, Gram-negative bacterial strains, isolated from clinical specimens between 2012 and 2016, were submitted to arup Laboratories for species identification. The lack of species- or genus-level matches in curated 16S rRNA gene databases prompted us to undertake the polyphasic characterization of these so far undescribed organisms. Six isolates available for additional testing were oxidase negative, catalase positive, pleomorphic, Gram-negative rods displaying temperature-dependent motility and producing yellow-pigmented colonies with three distinct morphotypes: medium-sized shiny, large mucoid and agar-pitting. Biochemical reactions and sugar fermentation patterns were most similar to members of the genus Serratia. Fatty acid profiles were highly similar across all six organisms, with the major components being: C16 : 0; C17 : 0 cyclo; C14 : 0 3-OH/iso-C16 : 1 I; C18 : 1 ω7c; and C16 : 1 ω7c/C16 : 1 ω6c. Whole-genome comparisons and multi locus sequence analysis (using the coding genes atpD, rpoB, gyrB and infB) suggest that the strains here described constitute three individual species within a novel genus related to the family Yersiniaceae. We propose for this novel taxon the name Chimaeribacter gen. nov., referring to the presentation of multiple characteristics typical of distinct Enterobacterales genera within a single organism. Four isolates are representative of a single species: Chimaeribacter arupi sp. nov (2016-Iso1, 2016-Iso2, type strain 2016-Iso3T=DSM 110101T=ATCC TSD-180T and 2013-Iso5). The remaining two isolates constitute the novel species Chimaeribacter coloradensis sp. nov. (type strain 2016-Iso4T=DSM 110102T=ATCC TSD-182T) and Chimaeribacter californicus sp. nov. (type strain 2015-Iso6T=DSM 110100T=ATCC TSD-181T). Our work provides the first formal characterization of the genus Chimaeribacter and forms the basis to study its taxonomic diversity.
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Affiliation(s)
- Alessandro Rossi
- Present address: Utah Public Health Laboratory, Taylorsville, Utah, USA.,Department of Pathology, University of Utah, Salt Lake City, Utah, USA.,Associated Regional and University Pathologists (ARUP) Laboratories, Salt Lake City, Utah, USA
| | - Mark A Fisher
- Associated Regional and University Pathologists (ARUP) Laboratories, Salt Lake City, Utah, USA.,Department of Pathology, University of Utah, Salt Lake City, Utah, USA
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7
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Jang H, Gopinath GR, Eshwar A, Srikumar S, Nguyen S, Gangiredla J, Patel IR, Finkelstein SB, Negrete F, Woo J, Lee Y, Fanning S, Stephan R, Tall BD, Lehner A. The Secretion of Toxins and Other Exoproteins of Cronobacter: Role in Virulence, Adaption, and Persistence. Microorganisms 2020; 8:E229. [PMID: 32046365 PMCID: PMC7074816 DOI: 10.3390/microorganisms8020229] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 01/28/2020] [Accepted: 02/06/2020] [Indexed: 12/29/2022] Open
Abstract
: Cronobacter species are considered an opportunistic group of foodborne pathogenic bacteria capable of causing both intestinal and systemic human disease. This review describes common virulence themes shared among the seven Cronobacter species and describes multiple exoproteins secreted by Cronobacter, many of which are bacterial toxins that may play a role in human disease. The review will particularly concentrate on the virulence factors secreted by C. sakazakii, C. malonaticus, and C. turicensis, which are the primary human pathogens of interest. It has been discovered that various species-specific virulence factors adversely affect a wide range of eukaryotic cell processes including protein synthesis, cell division, and ion secretion. Many of these factors are toxins which have been shown to also modulate the host immune response. These factors are encoded on a variety of mobile genetic elements such as plasmids and transposons; this genomic plasticity implies ongoing re-assortment of virulence factor genes which has complicated our efforts to categorize Cronobacter into sharply defined genomic pathotypes.
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Affiliation(s)
- Hyein Jang
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD 20708, USA; (H.J.); (J.G.); (F.N.); (J.W.); (Y.L.)
| | - Gopal R. Gopinath
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD 20708, USA; (H.J.); (J.G.); (F.N.); (J.W.); (Y.L.)
| | - Athmanya Eshwar
- Institute for Food Safety and Hygiene, University of Zurich, Zurich CH-8006 Zürich, Switzerland; (A.E.); (R.S.); (A.L.)
| | - Shabarinath Srikumar
- UCD-Centre for Food Safety, Science Centre South, University College Dublin, Dublin Belfield, Dublin 4, D04 V1W8, Ireland; (S.S.); (S.N.); (S.F.)
| | - Scott Nguyen
- UCD-Centre for Food Safety, Science Centre South, University College Dublin, Dublin Belfield, Dublin 4, D04 V1W8, Ireland; (S.S.); (S.N.); (S.F.)
| | - Jayanthi Gangiredla
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD 20708, USA; (H.J.); (J.G.); (F.N.); (J.W.); (Y.L.)
| | - Isha R. Patel
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD 20708, USA; (H.J.); (J.G.); (F.N.); (J.W.); (Y.L.)
| | - Samantha B. Finkelstein
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD 20708, USA; (H.J.); (J.G.); (F.N.); (J.W.); (Y.L.)
| | - Flavia Negrete
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD 20708, USA; (H.J.); (J.G.); (F.N.); (J.W.); (Y.L.)
| | - JungHa Woo
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD 20708, USA; (H.J.); (J.G.); (F.N.); (J.W.); (Y.L.)
| | - YouYoung Lee
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD 20708, USA; (H.J.); (J.G.); (F.N.); (J.W.); (Y.L.)
| | - Séamus Fanning
- UCD-Centre for Food Safety, Science Centre South, University College Dublin, Dublin Belfield, Dublin 4, D04 V1W8, Ireland; (S.S.); (S.N.); (S.F.)
| | - Roger Stephan
- Institute for Food Safety and Hygiene, University of Zurich, Zurich CH-8006 Zürich, Switzerland; (A.E.); (R.S.); (A.L.)
| | - Ben D. Tall
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD 20708, USA; (H.J.); (J.G.); (F.N.); (J.W.); (Y.L.)
| | - Angelika Lehner
- Institute for Food Safety and Hygiene, University of Zurich, Zurich CH-8006 Zürich, Switzerland; (A.E.); (R.S.); (A.L.)
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8
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Finkelstein S, Negrete F, Jang H, Gangiredla J, Mammel M, Patel IR, Chase HR, Woo J, Lee Y, Wang CZ, Weinstein L, Tall BD, Gopinath GR. Prevalence, Distribution, and Phylogeny of Type Two Toxin-Antitoxin Genes Possessed by Cronobacter Species where C. sakazakii Homologs Follow Sequence Type Lineages. Microorganisms 2019; 7:E554. [PMID: 31726673 PMCID: PMC6920972 DOI: 10.3390/microorganisms7110554] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/04/2019] [Accepted: 11/09/2019] [Indexed: 12/28/2022] Open
Abstract
Cronobacter species are a group of foodborne pathogenic bacteria that cause both intestinal and systemic human disease in individuals of all age groups. Little is known about the mechanisms that Cronobacter employ to survive and persist in foods and other environments. Toxin-antitoxin (TA) genes are thought to play a role in bacterial stress physiology, as well as in the stabilization of horizontally-acquired re-combinatorial elements such as plasmids, phage, and transposons. TA systems have been implicated in the formation of a persistence phenotype in some bacterial species including Escherichia coli and Salmonella. This project's goal was to understand the phylogenetic relatedness among TA genes present in Cronobacter. Preliminary studies showed that two typical toxin genes, fic and hipA followed species evolutionary lines. A local database of 22 TA homologs was created for Cronobacter sakazakii and a Python version 3 shell script was generated to extract TA FASTA sequences present in 234 C. sakazakii genomes previously sequenced as part of Center for Food Safety and Applied Nutrition's (CFSAN) GenomeTrakr project. BLAST analysis showed that not every C. sakazakii strain possessed all twenty-two TA loci. Interestingly, some strains contained either a toxin or an antitoxin component, but not both. Five common toxin genes: ESA_00258 (parDE toxin-antitoxin family), ESA_00804 (relBE family), ESA_01887 (relBE family), ESA_03838 (relBE family), and ESA_04273 (YhfG-Fic family) were selected for PCR analysis and the primers were designed to detect these genes. PCR analysis showed that 55 of 63 strains possessed three of these genes Sequence analysis identified homologs of the target genes and some of the strains were PCR-negative for one or more of the genes, pointing to potential nucleotide polymorphisms in those loci or that these toxin genes were absent. Phylogenetic studies using a Cronobacter pan genomic microarray showed that for the most part TAs follow species evolutionary lines except for a few toxin genes possessed by some C. malonaticus and C. universalis strains; this demonstrates that some TA orthologues share a common phylogeny. Within the C. sakazakii strains, the prevalence and distribution of these TA homologs by C. sakazakii strain BAA-894 (a powdered infant formula isolate) followed sequence-type evolutionary lineages. Understanding the phylogeny of TAs among the Cronobacter species is essential to design future studies to realize the physiological mechanisms and roles for TAs in stress adaptation and persistence of Cronobacter within food matrices and food processing environments.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Ben D. Tall
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 MuirKirk Rd, Laurel, MD 20708, USA; (S.F.); (F.N.); (H.J.); (J.G.); (M.M.); (I.R.P.); (H.R.C.); (J.W.); (Y.L.); (C.Z.W.); (L.W.); (G.R.G.)
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9
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Lu Y, Liu P, Li C, Sha M, Fang J, Gao J, Xu X, Matthews KR. Prevalence and Genetic Diversity of Cronobacter Species Isolated From Four Infant Formula Production Factories in China. Front Microbiol 2019; 10:1938. [PMID: 31497005 PMCID: PMC6712172 DOI: 10.3389/fmicb.2019.01938] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 08/07/2019] [Indexed: 12/30/2022] Open
Abstract
The aim of this study was to investigate the prevalence and genotypic characteristics of Cronobacter isolated from powdered infant formula (PIF) manufacturing facilities and to identify a potential source of contamination. A total of 42 Cronobacter isolates (5%) were detected in 835 environmental samples collected during the surveillance study. These isolates included C. sakazakii (n = 37), C. malonaticus (n = 3), and C. turicensis (n = 2). The isolates were divided into 14 sequence types (STs) by multi-locus sequence typing (MLST) and 21 pulsotypes (PTs) using pulsed-field gel electrophoresis (PFGE). The dominant C. sakazakii sequence types were ST3 (n = 12) and ST21 (n = 10), followed by ST136 (n = 6). The major PTs were PT22 (n = 12) and PT17 (n = 4) based on 100% similarity. Strains isolated from samples collected at the same production facility showed closer phylogenetic relation than those collected from distinct facilities. The result of extensive traceback sampling showed that PIF residues (PIF dust in production areas), fluid beds, drying areas, floors, and soil samples collected adjacent to the production facilities were the primary positive areas for Cronobacter. The present study outlines an effective approach to determine prevalence and genetic diversity of Cronobacter isolates associated with contamination of PIF.
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Affiliation(s)
- Yan Lu
- College of Food Science, Northeast Agricultural University, Harbin, China.,Green Food Research Institute of Heilongjiang (National Research Center of Dairy Engineering and Technology), Northeast Agricultural University, Harbin, China
| | - Peng Liu
- Green Food Research Institute of Heilongjiang (National Research Center of Dairy Engineering and Technology), Northeast Agricultural University, Harbin, China
| | - Changguo Li
- Food Department, Heilongjiang Administration for Market Regulation, Harbin, China
| | - Miao Sha
- Green Food Research Institute of Heilongjiang (National Research Center of Dairy Engineering and Technology), Northeast Agricultural University, Harbin, China
| | - Jingquan Fang
- Green Food Research Institute of Heilongjiang (National Research Center of Dairy Engineering and Technology), Northeast Agricultural University, Harbin, China
| | - Jingwen Gao
- Department of Food Science, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
| | - Xiaoxi Xu
- College of Food Science, Northeast Agricultural University, Harbin, China
| | - Karl R Matthews
- Department of Food Science, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
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10
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Aly MA, Domig KJ, Kneifel W, Reimhult E. Whole Genome Sequencing-Based Comparison of Food Isolates of Cronobacter sakazakii. Front Microbiol 2019; 10:1464. [PMID: 31333604 PMCID: PMC6615433 DOI: 10.3389/fmicb.2019.01464] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 06/11/2019] [Indexed: 12/13/2022] Open
Abstract
Cronobacter sakazakii is an emerging foodborne pathogen, which is linked to life-threatening infections causing septicemia, meningitis, and necrotizing enterocolitis. These infections have been epidemiologically connected to ingestion of contaminated reconstituted powder infant formula. Even at low water activity C. sakazakii can survive for a long time; it is capable of protective biofilm formation and occasionally shows high virulence and pathogenicity even following stressful environmental conditions. Hence it is a challenging task for the food industry to control contamination of food ingredients and products through the entire production chain, since an increasing number of severe food-related outbreaks of C. sakazakii infections has been observed. The seemingly great capability of C. sakazakii to survive even strict countermeasures combined with its prevalence in many food ingredients requires a greater in depth understanding of its virulence factors to master the food safety issues related to this organism. In this context, we present the whole genome sequence (WGS) of two different C. sakazakii isolated from skimmed milk powder (C7) and ready-to-eat salad mix (C8), respectively. These are compared to other, already sequenced, C. sakazakii genomes. Sequencing of the fusA allele revealed that both isolates were C. sakazakii. We investigated the molecular characteristics of both isolates relevant for genes associated with pathogenesis and virulence factors, resistance to stressful environmental conditions (e.g., osmotic and heat), survival in desiccation as well as conducted a comparative genomic analysis. By using multi-locus sequence typing (MLST), the genetic type of both isolates is assessed and the number of unique genes is determined. DNA of C. sakazakii C8 is shown to hold a novel and unique sequence type; the number of unique genes identified in the genomic sequence of C. sakazakii C7 and C8 were 109 and 188, respectively. Some of the determined unique genes such as the rhs and VgrG genes are linked to the Type VI Secretion System cluster, which is associated with pathogenicity and virulence factors. Moreover, seven genes encoding for multi-drug resistance were found in both isolates. The finding of a number of genes linked to producing capsules and biofilm are likely related to the observed resistance to desiccation.
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Affiliation(s)
- Mohamed A Aly
- Department of Nanobiotechnology, Institute for Biologically Inspired Materials, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria.,Department of Food Science, Faculty of Agriculture, Ain Shams University, Cairo, Egypt
| | - Konrad J Domig
- Department of Food Science and Technology, Institute of Food Science, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Wolfgang Kneifel
- Department of Food Science and Technology, Institute of Food Science, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Erik Reimhult
- Department of Nanobiotechnology, Institute for Biologically Inspired Materials, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
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11
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Chen Q, Jun L, Qiu Y, Zhao L. Short communication: Bioinformatics-based mining of novel gene targets for identification of Cronobacter turicensis using PCR. J Dairy Sci 2019; 102:6023-6026. [DOI: 10.3168/jds.2018-15929] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 02/12/2019] [Indexed: 01/13/2023]
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12
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13
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Jang H, Woo J, Lee Y, Negrete F, Finkelstein S, Chase HR, Addy N, Ewing L, Beaubrun JJG, Patel I, Gangiredla J, Eshwar A, Jaradat ZW, Seo K, Shabarinath S, Fanning S, Stephan R, Lehner A, Tall BD, Gopinath GR. Draft genomes of Cronobacter sakazakii strains isolated from dried spices bring unique insights into the diversity of plant-associated strains. Stand Genomic Sci 2018; 13:35. [PMID: 30519380 PMCID: PMC6267090 DOI: 10.1186/s40793-018-0339-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Accepted: 11/10/2018] [Indexed: 01/16/2023] Open
Abstract
Cronobacter sakazakii is a Gram-negative opportunistic pathogen that causes life- threatening infantile infections, such as meningitis, septicemia, and necrotizing enterocolitis, as well as pneumonia, septicemia, and urinary tract and wound infections in adults. Here, we report 26 draft genome sequences of C. sakazakii, which were obtained from dried spices from the USA, the Middle East, China, and the Republic of Korea. The average genome size of the C. sakazakii genomes was 4393 kb, with an average of 4055 protein coding genes, and an average genome G + C content of 56.9%. The genomes contained genes related to carbohydrate transport and metabolism, amino acid transport and metabolism, and cell wall/membrane biogenesis. In addition, we identified genes encoding proteins involved in osmotic responses such as DnaJ, Aquaproin Z, ProQ, and TreF, as well as virulence-related and heat shock-related proteins. Interestingly, a metabolic island comprised of a variably-sized xylose utilization operon was found within the spice-associated C. sakazakii genomes, which supports the hypothesis that plants may serve as transmission vectors or alternative hosts for Cronobacter species. The presence of the genes identified in this study can support the remarkable phenotypic traits of C. sakazakii such as the organism's capabilities of adaptation and survival in response to adverse growth environmental conditions (e.g. osmotic and desiccative stresses). Accordingly, the genome analyses provided insights into many aspects of physiology and evolutionary history of this important foodborne pathogen.
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Affiliation(s)
- Hyein Jang
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
| | - Jungha Woo
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
| | - Youyoung Lee
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
| | - Flavia Negrete
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
| | - Samantha Finkelstein
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
| | - Hannah R. Chase
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
| | - Nicole Addy
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
| | - Laura Ewing
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
| | - Junia Jean Gilles Beaubrun
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
| | - Isha Patel
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
| | - Jayanthi Gangiredla
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
| | - Athmanya Eshwar
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Ziad W. Jaradat
- Department of Nutrition and Food Technology, Jordan University of Science and Technology, Irbid, 22110 Jordan
| | - Kunho Seo
- Center for One Health, College of Veterinary Medicine, Konkuk University, Seoul, 05029 South Korea
| | - Srikumar Shabarinath
- UCD Centre for Food Safety, School of Public Health, Physiotherapy & Population Science, University College, Dublin, Ireland
- WHO Collaborating Centre for Cronobacter, Belfield, Dublin 4, Ireland
| | - Séamus Fanning
- UCD Centre for Food Safety, School of Public Health, Physiotherapy & Population Science, University College, Dublin, Ireland
- WHO Collaborating Centre for Cronobacter, Belfield, Dublin 4, Ireland
| | - Roger Stephan
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Angelika Lehner
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Ben D. Tall
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
| | - Gopal R. Gopinath
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708 USA
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14
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Alsonosi AM, Holy O, Forsythe SJ. Characterization of the pathogenicity of clinical Cronobacter malonaticus strains based on the tissue culture investigations. Antonie van Leeuwenhoek 2018; 112:435-450. [DOI: 10.1007/s10482-018-1178-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 10/05/2018] [Indexed: 02/06/2023]
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15
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Gopinath GR, Chase HR, Gangiredla J, Eshwar A, Jang H, Patel I, Negrete F, Finkelstein S, Park E, Chung T, Yoo Y, Woo J, Lee Y, Park J, Choi H, Jeong S, Jun S, Kim M, Lee C, Jeong H, Fanning S, Stephan R, Iversen C, Reich F, Klein G, Lehner A, Tall BD. Genomic characterization of malonate positive Cronobacter sakazakii serotype O:2, sequence type 64 strains, isolated from clinical, food, and environment samples. Gut Pathog 2018; 10:11. [PMID: 29556252 PMCID: PMC5845375 DOI: 10.1186/s13099-018-0238-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 03/02/2018] [Indexed: 02/06/2023] Open
Abstract
Background Malonate utilization, an important differential trait, well recognized as being possessed by six of the seven Cronobacter species is thought to be largely absent in Cronobacter sakazakii (Csak). The current study provides experimental evidence that confirms the presence of a malonate utilization operon in 24 strains of sequence type (ST) 64, obtained from Europe, Middle East, China, and USA; it offers explanations regarding the genomic diversity and phylogenetic relatedness among these strains, and that of other C. sakazakii strains. Results In this study, the presence of a malonate utilization operon in these strains was initially identified by DNA microarray analysis (MA) out of a pool of 347 strains obtained from various surveillance studies involving clinical, spices, milk powder sources and powdered infant formula production facilities in Ireland and Germany, and dried dairy powder manufacturing facilities in the USA. All ST64 C. sakazakii strains tested could utilize malonate. Zebrafish embryo infection studies showed that C. sakazakii ST64 strains are as virulent as other Cronobacter species. Parallel whole genome sequencing (WGS) and MA showed that the strains phylogenetically grouped as a separate clade among the Csak species cluster. Additionally, these strains possessed the Csak O:2 serotype. The nine-gene, ~ 7.7 kbp malonate utilization operon was located in these strains between two conserved flanking genes, gyrB and katG. Plasmidotyping results showed that these strains possessed the virulence plasmid pESA3, but in contrast to the USA ST64 Csak strains, ST64 Csak strains isolated from sources in Europe and the Middle East, did not possess the type six secretion system effector vgrG gene. Conclusions Until this investigation, the presence of malonate-positive Csak strains, which are associated with foods and clinical cases, was under appreciated. If this trait was used solely to identify Cronobacter strains, many strains would likely be misidentified. Parallel WGS and MA were useful in characterizing the total genome content of these Csak O:2, ST64, malonate-positive strains and further provides an understanding of their phylogenetic relatedness among other virulent C. sakazakii strains. Electronic supplementary material The online version of this article (10.1186/s13099-018-0238-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Gopal R Gopinath
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Hannah R Chase
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Jayanthi Gangiredla
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Athmanya Eshwar
- 2Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Hyein Jang
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Isha Patel
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Flavia Negrete
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Samantha Finkelstein
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Eunbi Park
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - TaeJung Chung
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - YeonJoo Yoo
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - JungHa Woo
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - YouYoung Lee
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Jihyeon Park
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Hyerim Choi
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Seungeun Jeong
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Soyoung Jun
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Mijeong Kim
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Chaeyoon Lee
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - HyeJin Jeong
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
| | - Séamus Fanning
- 3UCD Centre for Food Safety, School of Public Health, Physiotherapy & Population Science, University College, Dublin & WHO Collaborating Centre for Cronobacter, Belfield, Dublin 4, Ireland
| | - Roger Stephan
- 2Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Carol Iversen
- 2Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland.,3UCD Centre for Food Safety, School of Public Health, Physiotherapy & Population Science, University College, Dublin & WHO Collaborating Centre for Cronobacter, Belfield, Dublin 4, Ireland
| | - Felix Reich
- 4Institute for Food Quality and Safety, University of Veterinary Medicine Hannover, Bischofsholer Damm 15, 30173 Hannover, Germany
| | - Günter Klein
- 4Institute for Food Quality and Safety, University of Veterinary Medicine Hannover, Bischofsholer Damm 15, 30173 Hannover, Germany
| | - Angelika Lehner
- 2Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Ben D Tall
- 1Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708 USA
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16
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Scharinger EJ, Dietrich R, Wittwer T, Märtlbauer E, Schauer K. Multiplexed Lateral Flow Test for Detection and Differentiation of Cronobacter sakazakii Serotypes O1 and O2. Front Microbiol 2017; 8:1826. [PMID: 28979257 PMCID: PMC5611382 DOI: 10.3389/fmicb.2017.01826] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 09/06/2017] [Indexed: 01/28/2023] Open
Abstract
The ubiquitous and opportunistic pathogen Cronobacter sakazakii is responsible for severe meningitis, sepsis, and necrotizing enterocolitis in neonates and infants associated with ingestion of contaminated powdered infant formula (PIF). The current ISO method for isolation and detection of Cronobacter spp. is laborious, time-consuming and expensive. In this study, a multiplexed lateral flow test strip was developed to rapidly detect and simultaneously serotype O1 and O2 C. sakazakii serotypes. The assay is based on two monoclonal antibodies (MAb) that specifically bind to the lipopolysaccharides (LPS) of these pathogens. The test strip provides results very quickly; C. sakazakii could be detected in pure culture within 15 min with a sensitivity of 107 CFU/ml. After non-selective enrichment for 18 h as low as one Cronobacter cell per g PIF could be detected. Moreover, the established lateral flow assay (LFA) offers excellent specificity showing no cross-reactivity with other C. sakazakii serotypes, Cronobacter species or Enterobacteriaceae tested. These characteristics, together with several advantages such as speed, simplicity in performance, low analysis cost, and no requirement of specialized skills or sophisticated equipment make the developed multiplexed LFA suitable for reliable detection and serotyping of C. sakazakii serotypes O1 and O2.
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Affiliation(s)
- Eva J. Scharinger
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität MünchenOberschleißheim, Germany
| | - Richard Dietrich
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität MünchenOberschleißheim, Germany
| | | | - Erwin Märtlbauer
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität MünchenOberschleißheim, Germany
| | - Kristina Schauer
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität MünchenOberschleißheim, Germany
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17
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Tall BD, Gangiredla J, Grim CJ, Patel IR, Jackson SA, Mammel MK, Kothary MH, Sathyamoorthy V, Carter L, Fanning S, Iversen C, Pagotto F, Stephan R, Lehner A, Farber J, Yan QQ, Gopinath GR. Use of a Pan-Genomic DNA Microarray in Determination of the Phylogenetic Relatedness among Cronobacter spp. and Its Use as a Data Mining Tool to Understand Cronobacter Biology. MICROARRAYS 2017; 6:microarrays6010006. [PMID: 28273858 PMCID: PMC5374366 DOI: 10.3390/microarrays6010006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 02/08/2017] [Accepted: 02/21/2017] [Indexed: 11/24/2022]
Abstract
Cronobacter (previously known as Enterobacter sakazakii) is a genus of Gram-negative, facultatively anaerobic, oxidase-negative, catalase-positive, rod-shaped bacteria of the family Enterobacteriaceae. These organisms cause a variety of illnesses such as meningitis, necrotizing enterocolitis, and septicemia in neonates and infants, and urinary tract, wound, abscesses or surgical site infections, septicemia, and pneumonia in adults. The total gene content of 379 strains of Cronobacter spp. and taxonomically-related isolates was determined using a recently reported DNA microarray. The Cronobacter microarray as a genotyping tool gives the global food safety community a rapid method to identify and capture the total genomic content of outbreak isolates for food safety, environmental, and clinical surveillance purposes. It was able to differentiate the seven Cronobacter species from one another and from non-Cronobacter species. The microarray was also able to cluster strains within each species into well-defined subgroups. These results also support previous studies on the phylogenic separation of species members of the genus and clearly highlight the evolutionary sequence divergence among each species of the genus compared to phylogenetically-related species. This review extends these studies and illustrates how the microarray can also be used as an investigational tool to mine genomic data sets from strains. Three case studies describing the use of the microarray are shown and include: (1) the determination of allelic differences among Cronobacter sakazakii strains possessing the virulence plasmid pESA3; (2) mining of malonate and myo-inositol alleles among subspecies of Cronobacter dublinensis strains to determine subspecies identity; and (3) lastly using the microarray to demonstrate sequence divergence and phylogenetic relatedness trends for 13 outer-membrane protein alleles among 240 Cronobacter and phylogenetically-related strains. The goal of this review is to describe microarrays as a robust tool for genomics research of this assorted and important genus, a criterion toward the development of future preventative measures to eliminate this foodborne pathogen from the global food supply.
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Affiliation(s)
- Ben D Tall
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708, USA.
| | - Jayanthi Gangiredla
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708, USA.
| | - Christopher J Grim
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708, USA.
| | - Isha R Patel
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708, USA.
| | - Scott A Jackson
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708, USA.
- Complex Microbial Systems Group Biosystems and Biomaterials Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
| | - Mark K Mammel
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708, USA.
| | - Mahendra H Kothary
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708, USA.
| | - Venugopal Sathyamoorthy
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708, USA.
| | - Laurenda Carter
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708, USA.
| | - Séamus Fanning
- UCD Centre for Food Safety, School of Public Health, Physiotherapy & Population Science, University College, Dublin, Belfield, Dublin D04 N2E5, Ireland.
| | - Carol Iversen
- College of Life Sciences, University of Dundee, Dundee, DD1 5EH Scotland, UK.
| | - Franco Pagotto
- Food Directorate, Bureau of Microbial Hazards, Health Canada, Ottawa, ON K1A 0K9, Canada.
| | - Roger Stephan
- Institute for Food Safety and Hygiene, University of Zurich, Winterthurerstr. 272, CH-8057 Zurich, Switzerland.
| | - Angelika Lehner
- Institute for Food Safety and Hygiene, University of Zurich, Winterthurerstr. 272, CH-8057 Zurich, Switzerland.
| | - Jeffery Farber
- Department of Food Science, University of Guelph, Guelph, ON N1G 2W1, Canada.
| | - Qiong Q Yan
- UCD Centre for Food Safety, School of Public Health, Physiotherapy & Population Science, University College, Dublin, Belfield, Dublin D04 N2E5, Ireland.
| | - Gopal R Gopinath
- Center of Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD 20708, USA.
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18
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Eshwar AK, Tall BD, Gangiredla J, Gopinath GR, Patel IR, Neuhauss SCF, Stephan R, Lehner A. Linking Genomo- and Pathotype: Exploiting the Zebrafish Embryo Model to Investigate the Divergent Virulence Potential among Cronobacter spp. PLoS One 2016; 11:e0158428. [PMID: 27355472 PMCID: PMC4927158 DOI: 10.1371/journal.pone.0158428] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 06/15/2016] [Indexed: 12/04/2022] Open
Abstract
Bacteria belonging to the genus Cronobacter have been recognized as causative agents of life-threatening systemic infections primarily in premature, low-birth weight and immune-compromised neonates. Apparently not all Cronobacter species are linked to infantile infections and it has been proposed that virulence varies among strains. Whole genome comparisons and in silico analysis have proven to be powerful tools in elucidating potential virulence determinants, the presence/absence of which may explain the differential virulence behaviour of strains. However, validation of these factors has in the past been hampered by the availability of a suitable neonatal animal model. In the present study we have used zebrafish embryos to model Cronobacter infections in vivo using wild type and genetically engineered strains. Our experiments confirmed the role of the RepF1B-like plasmids as “virulence plasmids” in Cronobacter and underpinned the importantce of two putative virulence factors—cpa and zpx—in in vivo pathogenesis. We propose that by using this model in vivo infection studies are now possible on a large scale level which will boost the understanding on the virulence strategies employed by these pathogens.
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Affiliation(s)
- Athmanya K. Eshwar
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Ben D. Tall
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, Laurel, Maryland, United States of America
| | - Jayanthi Gangiredla
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, Laurel, Maryland, United States of America
| | - Gopal R. Gopinath
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, Laurel, Maryland, United States of America
| | - Isha R. Patel
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, Laurel, Maryland, United States of America
| | | | - Roger Stephan
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
| | - Angelika Lehner
- Institute for Food Safety and Hygiene, University of Zurich, Zurich, Switzerland
- * E-mail:
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19
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Martínez-García PM, López-Solanilla E, Ramos C, Rodríguez-Palenzuela P. Prediction of bacterial associations with plants using a supervised machine-learning approach. Environ Microbiol 2016; 18:4847-4861. [PMID: 27234490 DOI: 10.1111/1462-2920.13389] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 05/20/2016] [Accepted: 05/20/2016] [Indexed: 12/11/2022]
Abstract
Recent scenarios of fresh produce contamination by human enteric pathogens have resulted in severe food-borne outbreaks, and a new paradigm has emerged stating that some human-associated bacteria can use plants as secondary hosts. As a consequence, there has been growing concern in the scientific community about these interactions that have not yet been elucidated. Since this is a relatively new area, there is a lack of strategies to address the problem of food-borne illnesses due to the ingestion of fruits and vegetables. In the present study, we performed specific genome annotations to train a supervised machine-learning model that allows for the identification of plant-associated bacteria with a precision of ∼93%. The application of our method to approximately 9500 genomes predicted several unknown interactions between well-known human pathogens and plants, and it also confirmed several cases for which evidence has been reported. We observed that factors involved in adhesion, the deconstruction of the plant cell wall and detoxifying activities were highlighted as the most predictive features. The application of our strategy to sequenced strains that are involved in food poisoning can be used as a primary screening tool to determine the possible causes of contaminations.
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Affiliation(s)
- Pedro Manuel Martínez-García
- Área de Genética, Facultad de Ciencias, Instituto de Hortofruticultura Subtropical y Mediterránea 'La Mayora', Universidad de Málaga, Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Málaga, E-29071, Spain.,Centro de Biotecnología y Genómica de Plantas (CBGP), Universidad Politécnica de Madrid-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Parque Científico y Tecnológico de la Universidad Politécnica de Madrid. Campus de Montegancedo, Pozuelo de Alarcón, Madrid, 28223, Spain
| | - Emilia López-Solanilla
- Centro de Biotecnología y Genómica de Plantas (CBGP), Universidad Politécnica de Madrid-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Parque Científico y Tecnológico de la Universidad Politécnica de Madrid. Campus de Montegancedo, Pozuelo de Alarcón, Madrid, 28223, Spain.,Departamento de Biología Vegetal. Escuela Técnica Superior de Ingenieros Agrónomos, Universidad Politécnica de Madrid, Avenida Complutense, 3, Madrid, 28040, Spain
| | - Cayo Ramos
- Área de Genética, Facultad de Ciencias, Instituto de Hortofruticultura Subtropical y Mediterránea 'La Mayora', Universidad de Málaga, Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Málaga, E-29071, Spain
| | - Pablo Rodríguez-Palenzuela
- Centro de Biotecnología y Genómica de Plantas (CBGP), Universidad Politécnica de Madrid-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Parque Científico y Tecnológico de la Universidad Politécnica de Madrid. Campus de Montegancedo, Pozuelo de Alarcón, Madrid, 28223, Spain.,Departamento de Biología Vegetal. Escuela Técnica Superior de Ingenieros Agrónomos, Universidad Politécnica de Madrid, Avenida Complutense, 3, Madrid, 28040, Spain
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20
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Scharinger EJ, Dietrich R, Kleinsteuber I, Märtlbauer E, Schauer K. Simultaneous Rapid Detection and Serotyping of Cronobacter sakazakii Serotypes O1, O2, and O3 by Using Specific Monoclonal Antibodies. Appl Environ Microbiol 2016; 82:2300-2311. [PMID: 26850303 PMCID: PMC4959477 DOI: 10.1128/aem.04016-15] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 01/30/2016] [Indexed: 01/08/2023] Open
Abstract
Cronobacter sakazakii is a foodborne pathogen associated with rare but often lethal infections in neonates. Powdered infant formula (PIF) represents the most frequent source of infection. Out of the identified serotypes (O1 to O7), O1, O2, and O3 are often isolated from clinical and PIF samples. Serotype-specific monoclonal antibodies (MAbs) suitable for application in enzyme immunoassays (EIAs) for the rapid detection of C. sakazakii have not yet been developed. In this study, we created specific MAbs with the ability to bind toC. sakazakii of serotypes O1, O2, and O3. Characterization by indirect EIAs, immunofluorescence, motility assays, and immunoblotting identified lipopolysaccharide (LPS) and exopolysaccharide (EPS) as the antigenic determinants of the MAbs. The established sandwich EIAs were highly sensitive and were able to detect between 2 × 10(3)and 9 × 10(6)CFU/ml. Inclusivity tests confirmed that 93% of serotype O1 strains, 100% of O2 strains, and 87% of O3 strains were detected at low cell counts. No cross-reactivity with >100 strains of Cronobacter spp. and other Enterobacter iaceae was observed, except for that with C. sakazakii serotype O3 and Cronobacter muytjensii serotype O1. Moreover, the sandwich EIAs detected C. sakazakii in PIF samples artificially contaminated with 1 to 10 bacterial cells per 10 g of sample after 15 h of preenrichment. The use of these serotype-specific MAbs not only allows the reliable detection of C. sakazakii strains but also enables simultaneous serotyping in a simple sandwich EIA method.
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Affiliation(s)
- Eva J Scharinger
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität München, Oberschleißheim, Germany
| | - Richard Dietrich
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität München, Oberschleißheim, Germany
| | - Ina Kleinsteuber
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität München, Oberschleißheim, Germany
| | - Erwin Märtlbauer
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität München, Oberschleißheim, Germany
| | - Kristina Schauer
- Department of Veterinary Science, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität München, Oberschleißheim, Germany
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21
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Abstract
The Cronobacter group of pathogens, associated with severe and potentially life-threatening diseases, until recently were classified as a single species, Enterobacter sakazakii. The group was reclassified in 2007 into the genus Cronobacter as a member of the Enterobacteriaceae. This chapter outlines the history behind the epidemiology, analyzes how our understanding of these bacteria has evolved, and highlights the clinical significance the Cronobacter spp. have for neonatal and elderly patient populations and treatment of the associated infections.
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22
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The DSF type quorum sensing signalling system RpfF/R regulates diverse phenotypes in the opportunistic pathogen Cronobacter. Sci Rep 2016; 6:18753. [PMID: 26725701 PMCID: PMC4698668 DOI: 10.1038/srep18753] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 11/25/2015] [Indexed: 12/11/2022] Open
Abstract
Several bacterial pathogens produce diffusible signal factor (DSF)-type quorum sensing (QS) signals to control biofilm formation and virulence. Previous work showed that in Burkholderia cenocepacia the RpfFBc/RpfR system is involved in sensing and responding to DSF signals and that this signal/sensor gene pair is highly conserved in several bacterial species including Cronobacter spp. Here we show that C. turicensis LMG 23827T possesses a functional RpfF/R system that is involved in the regulation of various phenotypes, including colony morphology, biofilm formation and swarming motility. In vivo experiments using the zebrafish embryo model revealed a role of this regulatory system in virulence of this opportunistic pathogen. We provide evidence that the RpfF/R system modulates the intracellular c-di-GMP level of the organism, an effect that may underpin the alteration in phenotype and thus the regulated phenotypes may be a consequence thereof. This first report on an RpfF/R-type QS system of an organism outside the genus Burkholderia revealed that both the underlying molecular mechanisms as well as the regulated functions show a high degree of conservation.
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23
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Genome Sequence of Hydrocarbon-Degrading Cronobacter sp. Strain DJ34 Isolated from Crude Oil-Containing Sludge from the Duliajan Oil Fields, Assam, India. GENOME ANNOUNCEMENTS 2015; 3:3/6/e01321-15. [PMID: 26564043 PMCID: PMC4972779 DOI: 10.1128/genomea.01321-15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We report here the 4,856,096-bp draft genome sequence of hydrocarbon-degrading Cronobacter sp. strain DJ34 isolated from crude oil-containing sludge from the Duliajan oil fields, India. DJ34 contains genes that mediate hydrocarbon degradation, metal resistance, and biosurfactant production. This is the first report of the genome sequence of Cronobacter sp. inhabiting an oil-contaminated environment.
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24
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Yan Q, Wang J, Gangiredla J, Cao Y, Martins M, Gopinath GR, Stephan R, Lampel K, Tall BD, Fanning S. Comparative Genotypic and Phenotypic Analysis of Cronobacter Species Cultured from Four Powdered Infant Formula Production Facilities: Indication of Pathoadaptation along the Food Chain. Appl Environ Microbiol 2015; 81:4388-402. [PMID: 25911470 PMCID: PMC4475896 DOI: 10.1128/aem.00359-15] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 04/16/2015] [Indexed: 11/20/2022] Open
Abstract
Cronobacter species are opportunistic pathogens commonly found in the environment. Among the seven Cronobacter species, Cronobacter sakazakii sequence type 4 (ST-4) is predominantly associated with recorded cases of infantile meningitis. This study reports on a 26-month powdered infant formula (PIF) surveillance program in four production facilities located in distinct geographic regions. The objective was to identify the ST(s) in PIF production environments and to investigate the phenotypic features that support their survival. Of all 168 Cronobacter isolates, 133 were recovered from a PIF production environment, 31 were of clinical origin, and 4 were laboratory type strains. Sequence type 1 (n = 84 isolates; 63.9%) was the dominant type in PIF production environments. The majority of these isolates clustered with an indistinguishable pulsotype and persisted for at least an 18-month period. Moreover, DNA microarray results identified two phylogenetic lineages among ST-4 strains tested. Thereafter, the ST-1 and -4 isolates were phenotypically compared. Differences were noted based on the phenotypes expressed by these isolates. The ST-1 PIF isolates produced stronger biofilms at both 28°C and 37°C, while the ST-4 clinical isolates exhibited greater swimming activity and increased binding to Congo red dye. Given the fact that PIF is a low-moisture environment and that the clinical environment provides for an interaction between the pathogen and its host, these differences may be consistent with a form of pathoadaptation. These findings help to extend our current understanding of the epidemiology and ecology of Cronobacter species in PIF production environments.
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Affiliation(s)
- Qiongqiong Yan
- UCD Centre for Food Safety, WHO Collaborating Centre for Research, Reference & Training on Cronobacter, School of Public Health, Physiotherapy & Population Science, University College Dublin, Belfield, Dublin, Ireland
| | - Juan Wang
- UCD Centre for Food Safety, WHO Collaborating Centre for Research, Reference & Training on Cronobacter, School of Public Health, Physiotherapy & Population Science, University College Dublin, Belfield, Dublin, Ireland
| | - Jayanthi Gangiredla
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, OARSA, Silver Spring, Maryland, USA
| | - Yu Cao
- UCD Centre for Food Safety, WHO Collaborating Centre for Research, Reference & Training on Cronobacter, School of Public Health, Physiotherapy & Population Science, University College Dublin, Belfield, Dublin, Ireland
| | - Marta Martins
- UCD Centre for Food Safety, WHO Collaborating Centre for Research, Reference & Training on Cronobacter, School of Public Health, Physiotherapy & Population Science, University College Dublin, Belfield, Dublin, Ireland
| | - Gopal R Gopinath
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, OARSA, Silver Spring, Maryland, USA
| | - Roger Stephan
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Keith Lampel
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, OARSA, Silver Spring, Maryland, USA
| | - Ben D Tall
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, OARSA, Silver Spring, Maryland, USA
| | - Séamus Fanning
- UCD Centre for Food Safety, WHO Collaborating Centre for Research, Reference & Training on Cronobacter, School of Public Health, Physiotherapy & Population Science, University College Dublin, Belfield, Dublin, Ireland
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25
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Fehr A, Eshwar AK, Neuhauss SCF, Ruetten M, Lehner A, Vaughan L. Evaluation of zebrafish as a model to study the pathogenesis of the opportunistic pathogen Cronobacter turicensis. Emerg Microbes Infect 2015; 4:e29. [PMID: 26060602 PMCID: PMC4451267 DOI: 10.1038/emi.2015.29] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 03/13/2015] [Accepted: 03/31/2015] [Indexed: 11/22/2022]
Abstract
Bacteria belonging to the genus Cronobacter spp. have been recognized as causative agents of life-threatening systemic infections, primarily in premature, low-birth weight and/or immune-compromised neonates. Knowledge remains scarce regarding the underlying molecular mechanisms of disease development. In this study, we evaluated the use of a zebrafish model to study the pathogenesis of Cronobacter turicensis LMG 23827T, a clinical isolate responsible for two fatal sepsis cases in neonates. Here, the microinjection of approximately 50 colony forming units (CFUs) into the yolk sac resulted in the rapid multiplication of bacteria and dissemination into the blood stream at 24 h post infection (hpi), followed by the development of a severe bacteremia and larval death within 3 days. In contrast, the innate immune response of the embryos was sufficiently developed to control infection after the intravenous injection of up to 104 CFUs of bacteria. Infection studies using an isogenic mutant devoid of surviving and replicating in human macrophages (ΔfkpA) showed that this strain was highly attenuated in its ability to kill the larvae. In addition, the suitability of the zebrafish model system to study the effectiveness of antibiotics to treat Cronobacter infections in zebrafish embryos was examined. Our data indicate that the zebrafish model represents an excellent vertebrate model to study virulence-related aspects of this opportunistic pathogen in vivo.
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Affiliation(s)
- Alexander Fehr
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich , Winterthurerstrasse 268, 8057 Zurich, Switzerland
| | - Athmanya K Eshwar
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich , Winterthurerstrasse 272, 8057 Zurich, Switzerland
| | - Stephan C F Neuhauss
- Institute of Molecular Life Sciences, University of Zurich , Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Maja Ruetten
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich , Winterthurerstrasse 268, 8057 Zurich, Switzerland
| | - Angelika Lehner
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich , Winterthurerstrasse 272, 8057 Zurich, Switzerland
| | - Lloyd Vaughan
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich , Winterthurerstrasse 268, 8057 Zurich, Switzerland
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Hfq plays important roles in virulence and stress adaptation in Cronobacter sakazakii ATCC 29544. Infect Immun 2015; 83:2089-98. [PMID: 25754196 DOI: 10.1128/iai.03161-14] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 02/26/2015] [Indexed: 11/20/2022] Open
Abstract
Cronobacter spp. are opportunistic pathogens that cause neonatal meningitis and sepsis with high mortality in neonates. Despite the peril associated with Cronobacter infection, the mechanisms of pathogenesis are still being unraveled. Hfq, which is known as an RNA chaperone, participates in the interaction with bacterial small RNAs (sRNAs) to regulate posttranscriptionally the expression of various genes. Recent studies have demonstrated that Hfq contributes to the pathogenesis of numerous species of bacteria, and its roles are varied between bacterial species. Here, we tried to elucidate the role of Hfq in C. sakazakii virulence. In the absence of hfq, C. sakazakii was highly attenuated in dissemination in vivo, showed defects in invasion (3-fold) into animal cells and survival (10(3)-fold) within host cells, and exhibited low resistance to hydrogen peroxide (10(2)-fold). Remarkably, the loss of hfq led to hypermotility on soft agar, which is contrary to what has been observed in other pathogenic bacteria. The hyperflagellated bacteria were likely to be attributable to the increased transcription of genes associated with flagellar biosynthesis in a strain lacking hfq. Together, these data strongly suggest that hfq plays important roles in the virulence of C. sakazakii by participating in the regulation of multiple genes.
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27
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Influence of FkpA variants on survival and replication of Cronobacter spp. in human macrophages. Res Microbiol 2015; 166:186-95. [PMID: 25724920 DOI: 10.1016/j.resmic.2015.02.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 02/04/2015] [Accepted: 02/10/2015] [Indexed: 11/21/2022]
Abstract
Members of the genus Cronobacter are responsible for cases of meningitis and bacteremia with high fatality rates in neonates. Macrophage uptake of invading microbes is an innate process, and it has been proposed that macrophage infectivity potentiator (Mip) like proteins enhance the ability of pathogens to survive within macrophages. Cronobacter harbor the mip-like gene fkpA, but its role in intracellular survival of these bacteria in human macrophages has not yet been studied. Application of gentamicin exclusion assays and human THP-1 macrophage cells revealed significant differences in the capablility of Cronobacter species to survive and replicate within macrophages. Analysis to the amino acid level revealed both length and sequence variations in FkpA proteins among species. In this study, we addressed the possible influence of FkpA variants in intracellular survival of Cronobacter spp. in human macrophages, by knocking out the fkpA genes in two different Cronobacter strains and subsequent complementation with variants of the fkpA genes. Our results provide strong evidence that, in Cronobacter spp., FkpA must be considered a virulence factor, but its influence on macrophage survival and replication varies among strains and/or species due to the presence of amino acid variations.
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28
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Yan Q, Fanning S. Strategies for the identification and tracking of cronobacter species: an opportunistic pathogen of concern to neonatal health. Front Pediatr 2015; 3:38. [PMID: 26000266 PMCID: PMC4419663 DOI: 10.3389/fped.2015.00038] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 04/15/2015] [Indexed: 01/31/2023] Open
Abstract
Cronobacter species are emerging opportunistic food-borne pathogens, which consists of seven species, including C. sakazakii, C. malonaticus, C. muytjensii, C. turicensis, C. dublinensis, C. universalis, and C. condimenti. The organism can cause severe clinical infections, including necrotizing enterocolitis, septicemia, and meningitis, predominately among neonates <4 weeks of age. Cronobacter species can be isolated from various foods and their surrounding environments; however, powdered infant formula (PIF) is the most frequently implicated food source linked with Cronobacter infection. This review aims to provide a summary of laboratory-based strategies that can be used to identify and trace Cronobacter species. The identification of Cronobacter species using conventional culture method and immuno-based detection protocols were first presented. The molecular detection and identification at genus-, and species-level along with molecular-based serogroup approaches are also described, followed by the molecular sub-typing methods, in particular pulsed-field gel electrophoresis and multi-locus sequence typing. Next generation sequence approaches, including whole genome sequencing, DNA microarray, and high-throughput whole-transcriptome sequencing, are also highlighted. Appropriate application of these strategies would contribute to reduce the risk of Cronobacter contamination in PIF and production environments, thereby improving food safety and protecting public health.
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Affiliation(s)
- Qiongqiong Yan
- UCD-Centre for Food Safety, WHO Collaborating Centre for Research, Reference and Training on Cronobacter, School of Public Health, Physiotherapy and Population Science, University College Dublin , Dublin , Ireland
| | - Séamus Fanning
- UCD-Centre for Food Safety, WHO Collaborating Centre for Research, Reference and Training on Cronobacter, School of Public Health, Physiotherapy and Population Science, University College Dublin , Dublin , Ireland
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29
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A Cronobacter turicensis O1 antigen-specific monoclonal antibody inhibits bacterial motility and entry into epithelial cells. Infect Immun 2014; 83:876-87. [PMID: 25534937 DOI: 10.1128/iai.02211-14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Cronobacter turicensis is an opportunistic foodborne pathogen that can cause a rare but sometimes lethal infection in neonates. Little is known about the virulence mechanisms and intracellular lifestyle of this pathogen. In this study, we developed an IgG monoclonal antibody (MAb; MAb 2G4) that specifically recognizes the O1 antigen of C. turicensis cells. The antilipopolysaccharide antibody bound predominantly monovalently to the O antigen and reduced bacterial growth without causing cell agglutination. Furthermore, binding of the antibody to the O1 antigen of C. turicensis cells caused a significant reduction of the membrane potential which is required to energize flagellar rotation, accompanied by a decreased flagellum-based motility. These results indicate that binding of IgG to the O antigen of C. turicensis causes a direct antimicrobial effect. In addition, this feature of the antibody enabled new insight into the pathogenicity of C. turicensis. In a tissue culture infection model, pretreatment of C. turicensis with MAb 2G4 showed no difference in adhesion to human epithelial cells, whereas invasion of bacteria into Caco-2 cells was significantly inhibited.
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Plasmid-encoded MCP is involved in virulence, motility, and biofilm formation of Cronobacter sakazakii ATCC 29544. Infect Immun 2014; 83:197-204. [PMID: 25332122 DOI: 10.1128/iai.02633-14] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The aim of this study was to elucidate the function of the plasmid-borne mcp (methyl-accepting chemotaxis protein) gene, which plays pleiotropic roles in Cronobacter sakazakii ATCC 29544. By searching for virulence factors using a random transposon insertion mutant library, we identified and sequenced a new plasmid, pCSA2, in C. sakazakii ATCC 29544. An in silico analysis of pCSA2 revealed that it included six putative open reading frames, and one of them was mcp. The mcp mutant was defective for invasion into and adhesion to epithelial cells, and the virulence of the mcp mutant was attenuated in rat pups. In addition, we demonstrated that putative MCP regulates the motility of C. sakazakii, and the expression of the flagellar genes was enhanced in the absence of a functional mcp gene. Furthermore, a lack of the mcp gene also impaired the ability of C. sakazakii to form a biofilm. Our results demonstrate a regulatory role for MCP in diverse biological processes, including the virulence of C. sakazakii ATCC 29544. To the best of our knowledge, this study is the first to elucidate a potential function of a plasmid-encoded MCP homolog in the C. sakazakii sequence type 8 (ST8) lineage.
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31
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Larsen MH, Dalmasso M, Ingmer H, Langsrud S, Malakauskas M, Mader A, Møretrø T, Smole Možina S, Rychli K, Wagner M, John Wallace R, Zentek J, Jordan K. Persistence of foodborne pathogens and their control in primary and secondary food production chains. Food Control 2014. [DOI: 10.1016/j.foodcont.2014.03.039] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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32
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Plasmid-Mediated Antibiotic Resistance and Virulence in Gram-negatives: the Klebsiella pneumoniae Paradigm. Microbiol Spectr 2014; 2:1-15. [PMID: 25705573 DOI: 10.1128/microbiolspec.plas-0016-2013] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Plasmids harbor genes coding for specific functions including virulence factors and antibiotic resistance that permit bacteria to survive the hostile environment found in the host and resist treatment. Together with other genetic elements such as integrons and transposons, and using a variety of mechanisms, plasmids participate in the dissemination of these traits resulting in the virtual elimination of barriers among different kinds of bacteria. In this article we review the current information about physiology and role in virulence and antibiotic resistance of plasmids from the gram-negative opportunistic pathogen Klebsiella pneumoniae. This bacterium has acquired multidrug resistance and is the causative agent of serious communityand hospital-acquired infections. It is also included in the recently defined ESKAPE group of bacteria that cause most of US hospital infections.
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Jaradat ZW, Al Mousa W, Elbetieha A, Al Nabulsi A, Tall BD. Cronobacter spp.--opportunistic food-borne pathogens. A review of their virulence and environmental-adaptive traits. J Med Microbiol 2014; 63:1023-1037. [PMID: 24878566 DOI: 10.1099/jmm.0.073742-0] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The genus Cronobacter consists of a diverse group of Gram-negative bacilli and comprises seven species: Cronobacter sakazakii, Cronobacter malonaticus, Cronobacter muytjensii, Cronobacter turicensis, Cronobacter dublinensis, Cronobacter universalis and Cronobacter condimenti. Cronobacter are regarded as opportunistic pathogens, and have been implicated in newborn and infant infections, causing meningitis, necrotizing enterocolitis and bacteraemia or sepsis. Cronobacter virulence is believed to be due to multiple factors. Some strains were found to produce diarrhoea or cause significant fluid accumulation in suckling mice. Two iron acquisition systems (eitCBAD and iucABCD/iutA), Cronobacter plasminogen activator gene (cpa), a 17 kb type VI secretion system (T6SS), and a 27 kb filamentous haemagglutinin gene (fhaBC) and associated putative adhesins locus are harboured on a family of RepFIB-related plasmids (pESA3 and pCTU1), suggesting that these are common virulence plasmids; 98% of 229 tested Cronobacter strains possessed these plasmids. Even though pESA3 and pCTU1 share a common backbone composed of the repA gene and eitCBAD and iucABCD/iutA gene clusters, the presence of cpa, T6SS and FHA loci depended on species, demonstrating a strong correlation with the presence of virulence traits, plasmid type and species. Other factors were observed, in that Cronobacter form biofilms, and show unusual resistance to heat, dry and acid stress growth conditions. The outer-membrane protein A is probably one of the best-characterized virulence markers of Cronobacter. Furthermore, it was reported that Cronobacter employ phosphatidylinositide 3-kinase/Akt signalling, which activates protein kinase C-α and impairs the host cell's mitogen-activated protein kinase pathway, in order to invade cells. Cronobacter can also use immature dendritic cells and macrophages to escape the immune response. This review addresses the various virulence and environmental-adaptive characteristics possessed by members of the genus Cronobacter.
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Affiliation(s)
- Ziad W Jaradat
- Department of Biotechnology and Genetic Engineering, Jordan University of Science and Technology, PO Box 3030, Irbid 22110, Jordan
| | - Waseem Al Mousa
- Department of Biotechnology and Genetic Engineering, Jordan University of Science and Technology, PO Box 3030, Irbid 22110, Jordan
| | - Ahmed Elbetieha
- Department of Biotechnology and Genetic Engineering, Jordan University of Science and Technology, PO Box 3030, Irbid 22110, Jordan
| | - Anas Al Nabulsi
- Department of Nutrition and Food Technology, Jordan University of Science and Technology, PO Box 3030, Irbid 22110, Jordan
| | - Ben D Tall
- Food and Drug Administration, Center for Food Safety and Applied Nutrition, Division of Virulence Assessment, 8301 Muirkirk Road, Laurel, MD 20708, USA
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Tall BD, Chen Y, Yan Q, Gopinath GR, Grim CJ, Jarvis KG, Fanning S, Lampel KA. Cronobacter: an emergent pathogen causing meningitis to neonates through their feeds. Sci Prog 2014; 97:154-72. [PMID: 25108996 PMCID: PMC10365370 DOI: 10.3184/003685014x13994743930498] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The recognition of Cronobacter as a public health concern was raised when powdered infant formula (PIF) was linked to several neonatal meningitis outbreaks. It is an opportunistic pathogen that causes necrotising enterocolitis, infantile septicaemia, and meningitis which carries a high mortality rate among neonates. It has been also linked with cases of infection in adults and elderly. Over the past decade, much focus has been made on developing sensitive and specific characterisation, detection, and isolation methods to ascertain the quality of foods, notably contamination of PIF with Cronobacter and to understand its ability to cause disease. Whole genome sequencing has unveiled several putative virulence factors, yet the full capacity of the pathogenesis of Cronobacter has not yet been elucidated.
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Affiliation(s)
- Ben D. Tall
- Center for Food Safety and Applied Nutrition, Food and Drug Administration in Laurel, Maryland
| | - Yi Chen
- FDA in College Park, Maryland
| | | | - Gopal R. Gopinath
- Center for Food Safety and Applied Nutrition, FDA, in Laurel, Maryland
| | | | - Karen G. Jarvis
- Center for Food Safety and Applied Nutrition, FDA, in Laurel, Maryland
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Yan Q, Power KA, Cooney S, Fox E, Gopinath GR, Grim CJ, Tall BD, McCusker MP, Fanning S. Complete genome sequence and phenotype microarray analysis of Cronobacter sakazakii SP291: a persistent isolate cultured from a powdered infant formula production facility. Front Microbiol 2013; 4:256. [PMID: 24032028 PMCID: PMC3759002 DOI: 10.3389/fmicb.2013.00256] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 08/13/2013] [Indexed: 11/13/2022] Open
Abstract
Outbreaks of human infection linked to the powdered infant formula (PIF) food chain and associated with the bacterium Cronobacter, are of concern to public health. These bacteria are regarded as opportunistic pathogens linked to life-threatening infections predominantly in neonates, with an under developed immune system. Monitoring the microbiological ecology of PIF production sites is an important step in attempting to limit the risk of contamination in the finished food product. Cronobacter species, like other microorganisms can adapt to the production environment. These organisms are known for their desiccation tolerance, a phenotype that can aid their survival in the production site and PIF itself. In evaluating the genome data currently available for Cronobacter species, no sequence information has been published describing a Cronobacter sakazakii isolate found to persist in a PIF production facility. Here we report on the complete genome sequence of one such isolate, Cronobacter sakazakii SP291 along with its phenotypic characteristics. The genome of C. sakazakii SP291 consists of a 4.3-Mb chromosome (56.9% GC) and three plasmids, denoted as pSP291-1, [118.1-kb (57.2% GC)], pSP291-2, [52.1-kb (49.2% GC)], and pSP291-3, [4.4-kb (54.0% GC)]. When C. sakazakii SP291 was compared to the reference C. sakazakii ATCC BAA-894, which is also of PIF origin, the annotated genome data identified two interesting functional categories, comprising of genes related to the bacterial stress response and resistance to antimicrobial and toxic compounds. Using a phenotypic microarray (PM), we provided a full metabolic profile comparing C. sakazakii SP291 and the previously sequenced C. sakazakii ATCC BAA-894. These data extend our understanding of the genome of this important neonatal pathogen and provides further insights into the genotypes associated with features that can contribute to its persistence in the PIF environment.
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Affiliation(s)
- Qiongqiong Yan
- UCD Centre for Food Safety, WHO Collaborating Centre for Research, Reference and Training on Cronobacter, School of Public Health, Physiotherapy and Population Science, University College Dublin Dublin, Ireland
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Cronobacter: an emerging opportunistic pathogen associated with neonatal meningitis, sepsis and necrotizing enterocolitis. J Perinatol 2013; 33:581-5. [PMID: 23538645 DOI: 10.1038/jp.2013.26] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 01/24/2013] [Accepted: 02/11/2013] [Indexed: 11/08/2022]
Abstract
Members of the genus Cronobacter are an emerging group of opportunist Gram-negative pathogens. This genus was previously thought to be a single species, called Enterobacter sakazakii. Cronobacter spp. typically affect low-birth-weight neonates, causing life-threatening meningitis, sepsis and necrotizing enterocolitis. Outbreaks of disease have been associated with contaminated infant formula, although the primary environmental source remains elusive. Advanced understanding of these bacteria and better classification has been obtained by improved detection techniques and genomic analysis. Research has begun to characterize the virulence factors and pathogenic potential of Cronobacter. Investigations into sterilization techniques and protocols for minimizing the risk of contamination have been reviewed at national and international forums. In this review, we explore the clinical impact of Cronobacter neonatal and pediatric infections, discuss virulence and pathogenesis, and review prevention and treatment strategies.
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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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Characterization of pKP1433, a novel KPC-2-encoding plasmid from Klebsiella pneumoniae sequence type 340. Antimicrob Agents Chemother 2013; 57:3427-9. [PMID: 23629721 DOI: 10.1128/aac.00054-13] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The nucleotide sequence of pKP1433 (55,417 bp), a blaKPC-2-carrying plasmid from Klebsiella pneumoniae sequence type 340, was determined. pKP1433 displayed extensive sequence and structural similarities with the IncN plasmids possessing the KPC-2-encoding Tn4401b isoform. However, the replication, partitioning, and stability of pKP1433 were determined by sequences related to diverse non-IncN plasmids.
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Genome sequence of Cronobacter sakazakii SP291, a persistent thermotolerant isolate derived from a factory producing powdered infant formula. GENOME ANNOUNCEMENTS 2013; 1:e0008213. [PMID: 23516209 PMCID: PMC3622955 DOI: 10.1128/genomea.00082-13] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Cronobacter is an opportunistic pathogen associated with meningitis in neonates. Based on long-term surveillance of a powdered infant formula production facility, a persistent and thermotolerant isolate, denoted Cronobacter sakazakii SP291, was detected. Here we report the complete genome along with the sequences of three plasmids identified in this organism.
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Joseph S, Forsythe SJ. Insights into the Emergent Bacterial Pathogen Cronobacter spp., Generated by Multilocus Sequence Typing and Analysis. Front Microbiol 2012; 3:397. [PMID: 23189075 PMCID: PMC3504363 DOI: 10.3389/fmicb.2012.00397] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Accepted: 10/30/2012] [Indexed: 11/13/2022] Open
Abstract
Cronobacter spp. (previously known as Enterobacter sakazakii) is a bacterial pathogen affecting all age groups, with particularly severe clinical complications in neonates and infants. One recognized route of infection being the consumption of contaminated infant formula. As a recently recognized bacterial pathogen of considerable importance and regulatory control, appropriate detection, and identification schemes are required. The application of multilocus sequence typing (MLST) and analysis (MLSA) of the seven alleles atpD, fusA, glnS, gltB, gyrB, infB, and ppsA (concatenated length 3036 base pairs) has led to considerable advances in our understanding of the genus. This approach is supported by both the reliability of DNA sequencing over subjective phenotyping and the establishment of a MLST database which has open access and is also curated; http://www.pubMLST.org/cronobacter. MLST has been used to describe the diversity of the newly recognized genus, instrumental in the formal recognition of new Cronobacter species (C. universalis and C. condimenti) and revealed the high clonality of strains and the association of clonal complex 4 with neonatal meningitis cases. Clearly the MLST approach has considerable benefits over the use of non-DNA sequence based methods of analysis for newly emergent bacterial pathogens. The application of MLST and MLSA has dramatically enabled us to better understand this opportunistic bacterium which can cause irreparable damage to a newborn baby's brain, and has contributed to improved control measures to protect neonatal health.
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Affiliation(s)
- Susan Joseph
- Pathogen Research Group, School of Science and Technology, Nottingham Trent UniversityNottingham, UK
| | - Stephen J. Forsythe
- Pathogen Research Group, School of Science and Technology, Nottingham Trent UniversityNottingham, UK
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Joseph S, Desai P, Ji Y, Cummings CA, Shih R, Degoricija L, Rico A, Brzoska P, Hamby SE, Masood N, Hariri S, Sonbol H, Chuzhanova N, McClelland M, Furtado MR, Forsythe SJ. Comparative analysis of genome sequences covering the seven cronobacter species. PLoS One 2012; 7:e49455. [PMID: 23166675 PMCID: PMC3500316 DOI: 10.1371/journal.pone.0049455] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 10/09/2012] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Species of Cronobacter are widespread in the environment and are occasional food-borne pathogens associated with serious neonatal diseases, including bacteraemia, meningitis, and necrotising enterocolitis. The genus is composed of seven species: C. sakazakii, C. malonaticus, C. turicensis, C. dublinensis, C. muytjensii, C. universalis, and C. condimenti. Clinical cases are associated with three species, C. malonaticus, C. turicensis and, in particular, with C. sakazakii multilocus sequence type 4. Thus, it is plausible that virulence determinants have evolved in certain lineages. METHODOLOGY/PRINCIPAL FINDINGS We generated high quality sequence drafts for eleven Cronobacter genomes representing the seven Cronobacter species, including an ST4 strain of C. sakazakii. Comparative analysis of these genomes together with the two publicly available genomes revealed Cronobacter has over 6,000 genes in one or more strains and over 2,000 genes shared by all Cronobacter. Considerable variation in the presence of traits such as type six secretion systems, metal resistance (tellurite, copper and silver), and adhesins were found. C. sakazakii is unique in the Cronobacter genus in encoding genes enabling the utilization of exogenous sialic acid which may have clinical significance. The C. sakazakii ST4 strain 701 contained additional genes as compared to other C. sakazakii but none of them were known specific virulence-related genes. CONCLUSIONS/SIGNIFICANCE Genome comparison revealed that pair-wise DNA sequence identity varies between 89 and 97% in the seven Cronobacter species, and also suggested various degrees of divergence. Sets of universal core genes and accessory genes unique to each strain were identified. These gene sequences can be used for designing genus/species specific detection assays. Genes encoding adhesins, T6SS, and metal resistance genes as well as prophages are found in only subsets of genomes and have contributed considerably to the variation of genomic content. Differences in gene content likely contribute to differences in the clinical and environmental distribution of species and sequence types.
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Affiliation(s)
- Susan Joseph
- Pathogen Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
| | - Prerak Desai
- Vaccine Research Institute San Diego, San Diego, California, United States of America
| | - Yongmei Ji
- Life Technologies Corporation, Foster City, California, United States of America
| | - Craig A. Cummings
- Life Technologies Corporation, Foster City, California, United States of America
| | - Rita Shih
- Life Technologies Corporation, Foster City, California, United States of America
| | - Lovorka Degoricija
- Life Technologies Corporation, Foster City, California, United States of America
| | - Alain Rico
- Life Technologies Corporation, Darmstadt, Germany
| | - Pius Brzoska
- Life Technologies Corporation, Foster City, California, United States of America
| | - Stephen E. Hamby
- Bioinformatics and Biomathematics Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
| | - Naqash Masood
- Pathogen Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
| | - Sumyya Hariri
- Pathogen Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
| | - Hana Sonbol
- Pathogen Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
| | - Nadia Chuzhanova
- Bioinformatics and Biomathematics Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
| | - Michael McClelland
- Vaccine Research Institute San Diego, San Diego, California, United States of America
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, California, United States of America
| | - Manohar R. Furtado
- Life Technologies Corporation, Foster City, California, United States of America
| | - Stephen J. Forsythe
- Pathogen Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
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Multiplex PCR assay targeting a diguanylate cyclase-encoding gene, cgcA, to differentiate species within the genus Cronobacter. Appl Environ Microbiol 2012; 79:734-7. [PMID: 23144142 DOI: 10.1128/aem.02898-12] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In a comparison to the widely used Cronobacter rpoB PCR assay, a highly specific multiplexed PCR assay based on cgcA, a diguanylate cyclase gene, that identified all of the targeted six species among 305 Cronobacter isolates was designed. This assay will be a valuable tool for identifying suspected Cronobacter isolates from food-borne investigations.
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Diversity of the Cronobacter genus as revealed by multilocus sequence typing. J Clin Microbiol 2012; 50:3031-9. [PMID: 22785185 DOI: 10.1128/jcm.00905-12] [Citation(s) in RCA: 140] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cronobacter (previously known as Enterobacter sakazakii) is a diverse bacterial genus consisting of seven species: C. sakazakii, C. malonaticus, C. turicensis, C. universalis, C. muytjensii, C. dublinensis, and C. condimenti. In this study, we have used a multilocus sequence typing (MLST) approach employing the alleles of 7 genes (atpD, fusA, glnS, gltB, gyrB, infB, and ppsA; total length, 3,036 bp) to investigate the phylogenetic relationship of 325 Cronobacter species isolates. Strains were chosen on the basis of their species, geographic and temporal distribution, source, and clinical outcome. The earliest strain was isolated from milk powder in 1950, and the earliest clinical strain was isolated in 1953. The existence of seven species was supported by MLST. Intraspecific variation ranged from low diversity in C. sakazakii to extensive diversity within some species, such as C. muytjensii and C. dublinensis, including evidence of gene conversion between species. The predominant species from clinical sources was found to be C. sakazakii. C. sakazakii sequence type 4 (ST4) was the predominant sequence type of cerebral spinal fluid isolates from cases of meningitis.
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Identification and characterization of Cronobacter iron acquisition systems. Appl Environ Microbiol 2012; 78:6035-50. [PMID: 22706064 DOI: 10.1128/aem.01457-12] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Cronobacter spp. are emerging pathogens that cause severe infantile meningitis, septicemia, or necrotizing enterocolitis. Contaminated powdered infant formula has been implicated as the source of Cronobacter spp. in most cases, but questions still remain regarding the natural habitat and virulence potential for each strain. The iron acquisition systems in 231 Cronobacter strains isolated from different sources were identified and characterized. All Cronobacter spp. have both the Feo and Efe systems for acquisition of ferrous iron, and all plasmid-harboring strains (98%) have the aerobactin-like siderophore, cronobactin, for transport of ferric iron. All Cronobacter spp. have the genes encoding an enterobactin-like siderophore, although it was not functional under the conditions tested. Furthermore, all Cronobacter spp. have genes encoding five receptors for heterologous siderophores. A ferric dicitrate transport system (fec system) is encoded specifically by a subset of Cronobacter sakazakii and C. malonaticus strains, of which a high percentage were isolated from clinical samples. Phylogenetic analysis confirmed that the fec system is most closely related to orthologous genes present in human-pathogenic bacterial strains. Moreover, all strains of C. dublinensis and C. muytjensii encode two receptors, FcuA and Fct, for heterologous siderophores produced by plant pathogens. Identification of putative Fur boxes and expression of the genes under iron-depleted conditions revealed which genes and operons are components of the Fur regulon. Taken together, these results support the proposition that C. sakazakii and C. malonaticus may be more associated with the human host and C. dublinensis and C. muytjensii with plants.
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Yan QQ, Condell O, Power K, Butler F, Tall BD, Fanning S. Cronobacter species (formerly known as Enterobacter sakazakii) in powdered infant formula: a review of our current understanding of the biology of this bacterium. J Appl Microbiol 2012; 113:1-15. [PMID: 22420458 DOI: 10.1111/j.1365-2672.2012.05281.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Cronobacter species (formerly known as Enterobacter sakazakii) are opportunistic pathogens that can cause necrotizing enterocolitis, bacteraemia and meningitis, predominantly in neonates. Infection in these vulnerable infants has been linked to the consumption of contaminated powdered infant formula (PIF). Considerable research has been undertaken on this organism in the past number of years which has enhanced our understanding of this neonatal pathogen leading to improvements in its control within the PIF production environment. The taxonomy of the organism resulted in the recognition of a new genus, Cronobacter, which consists of seven species. This paper presents an up-to-date review of our current knowledge of Cronobacter species. Taxonomy, genome sequencing, current detection protocols and epidemiology are all discussed. In addition, consideration is given to the control of this organism in the manufacturing environment, as a first step towards reducing the occurrence of this pathogen in PIF.
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Affiliation(s)
- Q Q Yan
- UCD Centre for Food Safety, WHO Collaborating Centre for Research, Reference & Training on Cronobacter, School of Public Health, Physiotherapy & Population Science, University College Dublin, Dublin, Ireland
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Norberg S, Stanton C, Ross RP, Hill C, Fitzgerald GF, Cotter PD. Cronobacter spp. in powdered infant formula. J Food Prot 2012; 75:607-20. [PMID: 22410240 DOI: 10.4315/0362-028x.jfp-11-285] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Cronobacter species are opportunistic pathogens, and a mortality rate of 40 to 80% is associated with infections. This pathogen can cause a range of serious diseases such as meningitis, septicemia, necrotizing enterocolitis, and brain abscesses and has been responsible for a variety of sequelae such as quadriplegia. Although Cronobacter can cause disease in both adults and infants, infant infections associated with powdered formula are the focus of this review. Since the first reported Cronobacter infection outbreak in 1958, powdered infant formula has been identified as a major source of these outbreaks, resulting in many recalls of powdered infant formula worldwide. This contamination has created an immense problem for the powdered infant formula industry. In this review, we discuss the taxonomy of Cronobacter species, the natural habitat of Cronobacter and its presence in foods, the physiology, pathogenicity, and virulence of Cronobacter species, and available detection methods. We also discuss reported cases of Cronobacter infection linked to powdered infant formula consumption and then focus specifically on the official World Health Organization guidelines for preparation of powdered infant formula.
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Affiliation(s)
- Sarah Norberg
- Department of Microbiology, University College Cork, Cork, Ireland
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Jiang J, Li J, Kwan HS, Au CH, Wan Law PT, Li L, Kam KM, Lun Ling JM, Leung FC. A cost-effective and universal strategy for complete prokaryotic genomic sequencing proposed by computer simulation. BMC Res Notes 2012; 5:80. [PMID: 22289569 PMCID: PMC3296665 DOI: 10.1186/1756-0500-5-80] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2011] [Accepted: 01/31/2012] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Pyrosequencing techniques allow scientists to perform prokaryotic genome sequencing to achieve the draft genomic sequences within a few days. However, the assemblies with shotgun sequencing are usually composed of hundreds of contigs. A further multiplex PCR procedure is needed to fill all the gaps and link contigs into complete chromosomal sequence, which is the basis for prokaryotic comparative genomic studies. In this article, we study various pyrosequencing strategies by simulated assembling from 100 prokaryotic genomes. FINDINGS Simulation study shows that a single end 454 Jr. run combined with a paired end 454 Jr. run (8 kb library) can produce: 1) ~90% of 100 assemblies with < 10 scaffolds and ~95% of 100 assemblies with < 150 contigs; 2) average contig N50 size is over 331 kb; 3) average single base accuracy is > 99.99%; 4) average false gene duplication rate is < 0.7%; 5) average false gene loss rate is < 0.4%. CONCLUSIONS A single end 454 Jr. run combined with a paired end 454 Jr. run (8 kb library) is a cost-effective way for prokaryotic whole genome sequencing. This strategy provides solution to produce high quality draft assemblies for most of prokaryotic organisms within days. Due to the small number of assembled scaffolds, the following multiplex PCR procedure (for gap filling) would be easy. As a result, large scale prokaryotic whole genome sequencing projects may be finished within weeks.
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Affiliation(s)
- Jingwei Jiang
- School of Biological Sciences, Faculty of Science, The University of Hong Kong, Hong Kong, China.
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Genome sequence of Cronobacter sakazakii E899, a strain associated with human illness. J Bacteriol 2011; 193:5861. [PMID: 21952538 DOI: 10.1128/jb.05913-11] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cronobacter has caused numerous illnesses in neonates, infants, and children. Here we report the draft genome of Cronobacter sakazakii E899. Whole-genome sequence analysis of Cronobacter strains provides a tool for understanding the genomic regions specific to each individual species.
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Hamby SE, Joseph S, Forsythe SJ, Chuzhanova N. In Silico identification of pathogenic strains of Cronobacter from Biochemical data reveals association of inositol fermentation with pathogenicity. BMC Microbiol 2011; 11:204. [PMID: 21933417 PMCID: PMC3188490 DOI: 10.1186/1471-2180-11-204] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 09/20/2011] [Indexed: 11/11/2022] Open
Abstract
Background Cronobacter, formerly known as Enterobacter sakazakii, is a food-borne pathogen known to cause neonatal meningitis, septicaemia and death. Current diagnostic tests for identification of Cronobacter do not differentiate between species, necessitating time consuming 16S rDNA gene sequencing or multilocus sequence typing (MLST). The organism is ubiquitous, being found in the environment and in a wide range of foods, although there is variation in pathogenicity between Cronobacter isolates and between species. Therefore to be able to differentiate between the pathogenic and non-pathogenic strains is of interest to the food industry and regulators. Results Here we report the use of Expectation Maximization clustering to categorise 98 strains of Cronobacter as pathogenic or non-pathogenic based on biochemical test results from standard diagnostic test kits. Pathogenicity of a strain was postulated on the basis of either pathogenic symptoms associated with strain source or corresponding MLST sequence types, allowing the clusters to be labelled as containing either pathogenic or non-pathogenic strains. The resulting clusters gave good differentiation of strains into pathogenic and non-pathogenic groups, corresponding well to isolate source and MLST sequence type. The results also revealed a potential association between pathogenicity and inositol fermentation. An investigation of the genomes of Cronobacter sakazakii and C. turicensis revealed the gene for inositol monophosphatase is associated with putative virulence factors in pathogenic strains of Cronobacter. Conclusions We demonstrated a computational approach allowing existing diagnostic kits to be used to identify pathogenic strains of Cronobacter. The resulting clusters correlated well with MLST sequence types and revealed new information about the pathogenicity of Cronobacter species.
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Affiliation(s)
- Stephen E Hamby
- School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS, UK.
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Jiang J, Li J, Leung FC. A cost-effective and universal strategy for complete prokaryotic genome sequencing proposed by computer simulation. Genome Biol 2011. [DOI: 10.1186/1465-6906-12-s1-p6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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