1
|
Song D, Qi X, Huang Y, Jia A, Liang Y, Man C, Yang X, Jiang Y. Comparative proteomics reveals the antibiotic resistance and virulence of Cronobacter isolated from powdered infant formula and its processing environment. Int J Food Microbiol 2023; 407:110374. [PMID: 37678039 DOI: 10.1016/j.ijfoodmicro.2023.110374] [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: 05/26/2023] [Revised: 07/31/2023] [Accepted: 08/29/2023] [Indexed: 09/09/2023]
Abstract
Cronobacter species are opportunistic foodborne pathogens that can cause neonatal meningitis, sepsis, and necrotizing enterocolitis. In this genus, certain level strains have high mortality to infant (Cronobacter sakazakii and Cronobacter malonaticus) and antibiotic tolerance. Cronobacter has strong environmental tolerance (acid resistance, high temperature resistance, UV resistance, antibiotic resistance, etc.) and can survive in a variety of environments. It has been isolated in various production environments and products in several countries. However, the relationships between Cronobacter antibiotic tolerance and virulence remain unclear, especially at the molecular level. In this study, 96 strains of Cronobacter were isolated from powdered infant formula and its processing environment and screened for antibiotic tolerance, and proteomic maps of the representative strains of Cronobacter with antibiotic tolerance were generated by analyzing proteomics data using multiple techniques to identify protein that are implicated in Cronobacter virulence and antibiotic resistance. The increase in antibiotic tolerance of Cronobacter had a certain increase in the production of enterotoxin and hemolysin. Only triple tolerated Cronobacter sakazakii decreased the utilization of sialic acid. A total of 16,131 intracellular proteins were detected in eight representative strains, and different proteomes were present in strains with different antibiotic tolerance, including 56 virulence-related proteins. Multiple virulence proteins regulated by unknown genes were also found in the eight isolated representative strains.
Collapse
Affiliation(s)
- Danliangmin Song
- Department of Food Science, Northeast Agricultural University, Harbin 150038, China
| | - Xuehe Qi
- Department of Food Science, Northeast Agricultural University, Harbin 150038, China.
| | - Yan Huang
- Department of Food Science, Northeast Agricultural University, Harbin 150038, China
| | - Ai Jia
- Department of Food Science, Northeast Agricultural University, Harbin 150038, China
| | - Yaqi Liang
- Department of Food Science, Northeast Agricultural University, Harbin 150038, China
| | - Chaoxin Man
- Key Laboratory of Dairy Science, Ministry of Education, Harbin 150030, China.
| | - Xinyan Yang
- Key Laboratory of Dairy Science, Ministry of Education, Harbin 150030, China.
| | - Yujun Jiang
- Department of Food Science, Northeast Agricultural University, Harbin 150038, China.
| |
Collapse
|
2
|
Song D, Jia A, Liu B, Liu S, Dong K, Man C, Yang X, Jiang Y. Whole-transcriptome analysis after the acquisition of antibiotic resistance of Cronobacter sakazakii: Mechanisms of antibiotic resistance and virulence changes. Food Res Int 2023; 174:113664. [PMID: 37981356 DOI: 10.1016/j.foodres.2023.113664] [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: 08/07/2023] [Revised: 10/29/2023] [Accepted: 11/03/2023] [Indexed: 11/21/2023]
Abstract
The emergence of antibiotic-resistant bacteria led to the misuse of antibiotics, resulting in the emergence of more resistant bacteria and continuous improvement in their resistance ability. Cronobacter sakazakii (C. sakazakii) has been considered a pathogen that harms infants. Incidents of C. sakazakii contamination have continued globally, several studies have indicated that C. sakazakii is increasingly resistant to antibiotics. A few studies have explored the mechanism of antibiotic resistance in C. sakazakii, and some have examined the antibiotic resistance and changes in virulence levels. We aimed to investigate the antibiotic resistance mechanism and virulence differences in C. sakazakii. The level of virulence factors of C. sakazakii was modified after induction by antibiotics compared with the antibiotic-sensitive strains, and the XS001-Ofl group had the strongest capacity to produce enterotoxin (85.18 pg/mL) and hemolysin (1.47 ng/mL). The biofilm formation capacity after induction significantly improved. The number of bases and mapped reads in all groups accounted for more than 55 % and 70 %, as detected by transcriptomic analysis. The resistance mechanism of different antibiotics was more common in efflux pumps, cationic antimicrobial peptides, and biofilm formation pathways. The level of antibiotic resistance mainly affected the expression of virulence genes associated with flagella assembly and synthesis.
Collapse
Affiliation(s)
- Danliangmin Song
- Key Laboratory of Dairy Science, Ministry of Education, Department of Food Science, Northeast Agricultural University, Harbin, 150030, China.
| | - Ai Jia
- Key Laboratory of Dairy Science, Ministry of Education, Department of Food Science, Northeast Agricultural University, Harbin, 150030, China.
| | - Biqi Liu
- Key Laboratory of Dairy Science, Ministry of Education, Department of Food Science, Northeast Agricultural University, Harbin, 150030, China.
| | - Shiyu Liu
- Key Laboratory of Dairy Science, Ministry of Education, Department of Food Science, Northeast Agricultural University, Harbin, 150030, China.
| | - Kai Dong
- Key Laboratory of Dairy Science, Ministry of Education, Department of Food Science, Northeast Agricultural University, Harbin, 150030, China.
| | - Chaoxin Man
- Key Laboratory of Dairy Science, Ministry of Education, Harbin 150030, China.
| | - Xinyan Yang
- Key Laboratory of Dairy Science, Ministry of Education, Harbin 150030, China.
| | - Yujun Jiang
- Key Laboratory of Dairy Science, Ministry of Education, Department of Food Science, Northeast Agricultural University, Harbin, 150030, China.
| |
Collapse
|
3
|
Cechin CDF, Carvalho GG, Bastos CP, Kabuki DY. Cronobacter spp. in foods of plant origin: occurrence, contamination routes, and pathogenic potential. Crit Rev Food Sci Nutr 2023; 63:12398-12412. [PMID: 35866516 DOI: 10.1080/10408398.2022.2101426] [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] [Indexed: 11/03/2022]
Abstract
Cronobacter is an emerging bacterial pathogen associated with infections such as necrotizing enterocolitis, sepsis, and meningitis in neonates and infants, related to the consumption of powdered infant formula. In addition, this bacterium can also cause infections in adults by the ingestion of other foods. Thus, this review article aims to report the occurrence and prevalence of Cronobacter spp. in foods of plant origin, as well as the possible sources and routes of contamination in these products, and the presence of pathogenic strains in these foods. Cronobacter was present in a wide variety of cereal-based foods, vegetables, herbs, spices, ready-to-eat foods, and foods from other categories. This pathogen was also found in cultivation environments, such as soils, compost, animal feces, rice and vegetable crops, as well as food processing industries, and domestic environments, thus demonstrating possible contamination routes. Furthermore, sequence types (ST) involved in clinical cases and isolates resistant to antibiotics were found in Cronobacter strains isolated from food of plant origin. The identification of Cronobacter spp. in plant-based foods is of great importance to better elucidate the vehicles and routes of contamination in the primary production chain and processing facility, until the final consumption of the food, to prevent infections.
Collapse
Affiliation(s)
- Carine da Fonseca Cechin
- Department of Food Science and Nutrition, School of Food Engineering, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Gabriela Guimarães Carvalho
- Department of Food Science and Nutrition, School of Food Engineering, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Caroline Peixoto Bastos
- Center of Chemical, Pharmaceutical and Food Sciences, Federal University of Pelotas (UFPel), Pelotas, Rio Grande do Sul, Brazil
| | - Dirce Yorika Kabuki
- Department of Food Science and Nutrition, School of Food Engineering, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| |
Collapse
|
4
|
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.
Collapse
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
| |
Collapse
|
5
|
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.
Collapse
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.)
| |
Collapse
|
6
|
Cal-Sabater P, Caro I, Castro MJ, Cao MJ, Mateo J, Quinto EJ. Flow Cytometry to Assess the Counts and Physiological State of Cronobacter sakazakii Cells after Heat Exposure. Foods 2019; 8:foods8120688. [PMID: 31888256 PMCID: PMC6963341 DOI: 10.3390/foods8120688] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 12/06/2019] [Accepted: 12/11/2019] [Indexed: 11/26/2022] Open
Abstract
Cronobacter sakazakii is an opportunistic pathogen that is associated with outbreaks of neonatal necrotizing enterocolitis, septicaemia, and meningitis. Reconstituted powdered infant formulae is the most common vehicle of infection. The aim of the present study is to gain insight into the physiological states of C. sakazakii cells using flow cytometry to detect the compromised cells, which are viable but non-culturable using plate-based methods, and to evaluate the impact of milk heat treatments on those populations. Dead-cell suspensions as well as heat-treated and non-heat-treated cell suspensions were used. After 60 or 65 °C treatments, the number of compromised cells increased as a result of cells with compromised membranes shifting from the heat-treated suspension. These temperatures were not effective at killing all bacteria but were effective at compromising their membranes. Thus, mild heat treatments are not enough to guarantee the safety of powered infant formulae. Flow cytometry was capable of detecting C. sakazakii’s compromised cells that cannot be detected with classical plate count methods; thus, it could be used as a screening test to decrease the risk derived from the presence of pathogenic viable but non-culturable cells in this food that is intended for newborns’ nutrition.
Collapse
Affiliation(s)
- Paloma Cal-Sabater
- Department of Nutrition and Food Science, Faculty of Medicine, University of Valladolid, 47005 Valladolid, Spain; (P.C.-S.); (I.C.)
- Department of Nursery, Faculty of Nursery, University of Valladolid, 47005 Valladolid, Spain; (M.J.C.); (M.J.C.)
| | - Irma Caro
- Department of Nutrition and Food Science, Faculty of Medicine, University of Valladolid, 47005 Valladolid, Spain; (P.C.-S.); (I.C.)
| | - María J. Castro
- Department of Nursery, Faculty of Nursery, University of Valladolid, 47005 Valladolid, Spain; (M.J.C.); (M.J.C.)
| | - María J. Cao
- Department of Nursery, Faculty of Nursery, University of Valladolid, 47005 Valladolid, Spain; (M.J.C.); (M.J.C.)
| | - Javier Mateo
- Department of Hygiene and Food Technology, Faculty of Veterinary Medicine, University of León, 24071 León, Spain;
| | - Emiliano J. Quinto
- Department of Nutrition and Food Science, Faculty of Medicine, University of Valladolid, 47005 Valladolid, Spain; (P.C.-S.); (I.C.)
- Correspondence:
| |
Collapse
|
7
|
Odeyemi OA, Abdullah Sani N. Antibiotic resistance, putative virulence factors and curli fimbrination among Cronobacter species. Microb Pathog 2019; 136:103665. [PMID: 31404630 DOI: 10.1016/j.micpath.2019.103665] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 08/09/2019] [Accepted: 08/09/2019] [Indexed: 01/27/2023]
Abstract
This study aimed to investigate antibiotic resistance and putative virulence factors among Cronobacter sakazakii isolated from powdered infant formula and other sources. The following 9 cultures (CR1-9) were collected from our culture collection: C. sakazakii and 3 Cronobacter species: C. sakazakii ATCC® 29544™, C. muytjensii ATCC® 51329™, C. turicensis E866 were used in this study. Isolates were subjected to antibiotic susceptibility and the following virulence factors (protease, DNase, haemolysin, gelatinase, motility and biofilm formation) using phenotypic methods. All the bacteria were able to form biofilm on agar at 37 °C and were resistant to ampicillin, erythromycin, fosfomycin and sulphamethoxazole. It was observed from this study that tested strains formed weak and strong biofilm with violet dry and rough (rdar), brown dry and rough (bdar), red mucoid and smooth (rmas) colony morphotypes on Congo red agar. Rdar expresses curli and fimbriae, while bdar expresses curli. Both biofilm colony morphotypes are commonly found in Enterobacteriaceae including Salmonella species. This study also reveals a new colony morphotypes in Cronobacter species. Conclusively, there was correlation between putative virulence factors and antibiotic resistance among the tested bacteria. Further study on virulence and antibiotic resistance genes is hereby encouraged.
Collapse
Affiliation(s)
- O A Odeyemi
- Aquaculture Microbiology Laboratory, Ecology and Biodiversity Centre, Institute for Marine and Antarctic Studies, University of Tasmania, Launceston, Australia; Food Safety, Security and Quality Research Group, Centre for Biotechnology and Functional Food, Faculty of Science and Technology, National University of Malaysia (UKM), Bangi, 43600, Selangor, Malaysia
| | - N Abdullah Sani
- Food Safety, Security and Quality Research Group, Centre for Biotechnology and Functional Food, Faculty of Science and Technology, National University of Malaysia (UKM), Bangi, 43600, Selangor, Malaysia.
| |
Collapse
|
8
|
|
9
|
Jia X, Hua J, Liu L, Xu Z, Li Y. Phenotypic characterization of pathogenic Cronobacter spp. strains. Microb Pathog 2018; 121:232-237. [PMID: 29800699 DOI: 10.1016/j.micpath.2018.05.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 05/15/2018] [Accepted: 05/22/2018] [Indexed: 01/14/2023]
Abstract
BACKGROUND Cronobacter species are Gram-negative opportunistic foodborne pathogens that may cause enterocolitis, bacteremia and meningitis in neonates and premature neonates. Lipopolysaccharide (LPS) serves as the major component of the outer membrane of cell, is a potential virulence factor for Cronobacter. METHODS Given the potential importance of this molecule in infection and virulence, SDS-PAGE of LPS, MS and TLC characterization of phospholipids and phenotypic characterization of Cronobacter spp. strains were carried out. RESULT The phospholipids from Cronobacter yielded four major peaks at m/z 719.9, 733.9, 747.9 and 773.9 in the spectrum. All Cronobacter showed O-antigen bands except C. muytjensii ATCC 51329. When Cronobacter defect O-antigen, the outer membrane permeability and cell surface hydrophobicities are increased. All Cronobacter are able to grow under pH 5.0 condition and able to grow under 6% NaCl concentration. C. dublinensis DSM 18705 has a higher infection rate to Caco-2 cells than other Cronobacter. CONCLUSION Invasion of pathogens into a host cell is critical component to an infectious case. And C. dublinensis DSM 18705 has a higher infection rate to Caco-2 cells than other Cronobacter.
Collapse
Affiliation(s)
- Xiangyin Jia
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China; Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China
| | - Jingjing Hua
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China; Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China
| | - Lu Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China; Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China
| | - Zhenbo Xu
- School of Food Science and Engineering, South China University of Technology, Guangzhou, 510640, China; Department of Microbial Pathogenesis, University of Maryland, Baltimore, 21201, USA; Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Guangzhou, 510640, China.
| | - Yanyan Li
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China; Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, China.
| |
Collapse
|
10
|
Du XJ, Han R, Li P, Wang S. Comparative proteomic analysis of Cronobacter sakazakii isolates with different virulences. J Proteomics 2015; 128:344-51. [PMID: 26327241 DOI: 10.1016/j.jprot.2015.08.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 07/24/2015] [Accepted: 08/21/2015] [Indexed: 10/23/2022]
Abstract
UNLABELLED Cronobacter is a genus of widespread, opportunistic, foodborne pathogens that can result in serious illnesses in at-risk infants because of their immature immunity and high dependence on powdered formula, which is one of the foods most often contaminated by this pathogen. However, limited information is available regarding the pathogenesis and the specific virulence factors of this species. In this study, the virulences of 42 Cronobacter sakazakii isolates were analyzed by infecting neonatal SD rats. A comparison of the typing patterns of the isolates enabled groups with close relationships but that exhibited distinct pathogenesis to be identified. Among these groups, 2 strains belonging to the same group but showing distinct virulences were selected, and 2-DE was applied to identify differentially expressed proteins, focusing on virulence-related proteins. A total of 111 protein spots were identified using matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF/TOF-MS), and 89 were successfully identified. Further analysis suggested that at least 11 of these proteins may be involved in the pathogenesis of this pathogen. Real-time PCR was carried out to further confirm the differential expression pattern of the genes, and the results indicated that the mRNA expression levels were consistent with the protein expression levels. BIOLOGICAL SIGNIFICANCE The virulence factors and pathogenesis of Cronobacter are largely unknown. In combination with animal toxicological experiments and subtyping results of C. sakazakii, comparative proteomics analysis was performed to comprehensively evaluate the differentially expressed proteins of two isolates that exhibited distinct virulence but were closely related. These procedures made it possible to identify the virulence-related of factors of Cronobacter. Among the 89 total identified proteins, at least 11 show virulence-related potential. This work provides comprehensive candidates for the further investigation of the pathogenesis of Cronobacter.
Collapse
Affiliation(s)
- Xin-jun Du
- Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Ran Han
- Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Ping Li
- Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Shuo Wang
- Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China.
| |
Collapse
|
11
|
Singh N, Goel G, Raghav M. Insights into virulence factors determining the pathogenicity of Cronobacter sakazakii. Virulence 2015; 6:433-40. [PMID: 25950947 PMCID: PMC4601314 DOI: 10.1080/21505594.2015.1036217] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 03/25/2015] [Accepted: 03/26/2015] [Indexed: 02/07/2023] Open
Abstract
Cronobacter sakazakii is an opportunistic pathogen associated with outbreaks of life-threatening necrotizing enterocolitis, meningitis and sepsis in neonates and infants. The pathogen possesses an array of virulence factors which aid in tissue adhesion, invasion and host cell injury. Although the identification and validation of C. sakazakii virulence factors has been hindered by availability of suitable neonatal animal model, various studies has reported outer membrane protein A (ompA) as a potential virulence marker. Various other plasmid associated genes such as filamentous hemagglutinin (fhaBC), Cronobacter plasminogen activator (cpa) and genes responsible for iron acquisition (eitCBAD and iucABD/iutA) have been reported in different strains of C. sakazakii. Besides these proposed virulence factors, several biophysical growth factors such as formation of biofilms and resistance to various environmental stresses also contributes to the pathogenic potential of this pathogen. This review provides an update on virulence determinants associated with the pathogenesis of C. sakazakii. The potential reservoirs of the pathogen, mode of transmission and epidemiology are also discussed.
Collapse
Affiliation(s)
- Niharika Singh
- Department of Biotechnology and Bioinformatics; Jaypee University of Information Technology; Waknaghat, Solan, India
| | - Gunjan Goel
- Department of Biotechnology and Bioinformatics; Jaypee University of Information Technology; Waknaghat, Solan, India
| | - Mamta Raghav
- Department of Biotechnology and Bioinformatics; Jaypee University of Information Technology; Waknaghat, Solan, India
| |
Collapse
|
12
|
Kong D, Liu L, Xing C, Kuang H, Xu C. Sensitive and highly specific detection ofCronobacter sakazakiibased on monoclonal sandwich ELISA. FOOD AGR IMMUNOL 2015. [DOI: 10.1080/09540105.2014.998634] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
|
13
|
Feeney A, Kropp KA, O’Connor R, Sleator RD. Cronobacter sakazakii: stress survival and virulence potential in an opportunistic foodborne pathogen. Gut Microbes 2015; 5:711-8. [PMID: 25562731 PMCID: PMC4615781 DOI: 10.4161/19490976.2014.983774] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
A characteristic feature of the opportunistic foodborne pathogen Cronobacter sakazakii is its ability to survive in extremely arid environments, such as powdered infant formula, making it a dangerous opportunistic pathogen of individuals of all age groups, especially infants and neonates. Herein, we provide a brief overview of the pathogen; clinical manifestations, environmental reservoirs and our current understanding of stress response mechanisms and virulence factors which allow it to cause disease.
Collapse
Affiliation(s)
- Audrey Feeney
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland
| | - Kai A Kropp
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland
| | - Roxana O’Connor
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland
| | - Roy D Sleator
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland,Correspondence to: Roy D Sleator;
| |
Collapse
|
14
|
Fakruddin M, Rahaman M, Ahmed MM, Hoque MM. Stress tolerant virulent strains of Cronobacter sakazakii from food. Biol Res 2014; 47:63. [PMID: 25723712 PMCID: PMC4335510 DOI: 10.1186/0717-6287-47-63] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 11/10/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cronobacter sakazakii is considered as an emerging foodborne pathogen. The aim of this study was to isolate and characterize virulent strains of Cronobacter sakazakii from food samples of Bangladesh. RESULT Six (6) Cronobacter sakazakii was isolated and identified from 54 food samples on the basis of biochemical characteristics, sugar fermentation, SDS-PAGE of whole cell protein, plasmid profile and PCR of Cronobacter spp. specific genes (esak, gluA, zpx, ompA, ERIC, BOX-AIR) and sequencing. These strains were found to have moderately high antibiotic resistance against common antibiotics and some are ESBL producer. Most of the C. sakazakii isolates were capable of producing biofilm (strong biofilm producer), extracellular protease and siderophores, curli expression, haemolysin, haemagglutinin, mannose resistant haemagglutinin, had high cell surface hydrophobicity, significant resistance to human serum, can tolerate high concentration of salt, bile and DNase production. Most of them produced enterotoxins of different molecular weight. The isolates pose significant serological cross-reactivity with other gram negative pathogens such as serotypes of Salmonella spp., Shigella boydii, Shigella sonnei, Shigella flexneri and Vibrio cholerae. They had significant tolerance to high temperature, low pH, dryness and osmotic stress. CONCLUSION Special attention should be given in ensuring hygiene in production and post-processing to prevent contamination of food with such stress-tolerant virulent Cronobacter sakazakii.
Collapse
Affiliation(s)
- Md Fakruddin
- Industrial Microbiology Laboratory, Institute of Food Science and Technology (IFST), Bangladesh Council of Scientific and Industrial Research (BCSIR), Dhaka, Bangladesh.
| | - Mizanur Rahaman
- Department of Microbiology, University of Dhaka, Dhaka, Bangladesh.
| | - Monzur Morshed Ahmed
- Industrial Microbiology Laboratory, Institute of Food Science and Technology (IFST), Bangladesh Council of Scientific and Industrial Research (BCSIR), Dhaka, Bangladesh.
| | | |
Collapse
|
15
|
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.
Collapse
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
| |
Collapse
|
16
|
|
17
|
Ivy RA, Farber JM, Pagotto F, Wiedmann M. International Life Science Institute North America Cronobacter (Formerly Enterobacter sakazakii) isolate set. J Food Prot 2013; 76:40-51. [PMID: 23317855 DOI: 10.4315/0362-028x.jfp-11-546] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Foodborne pathogen isolate collections are important for the development of detection methods, for validation of intervention strategies, and to develop an understanding of pathogenesis and virulence. We have assembled a publicly available Cronobacter (formerly Enterobacter sakazakii) isolate set that consists of (i) 25 Cronobacter sakazakii isolates, (ii) two Cronobacter malonaticus isolates, (iii) one Cronobacter muytjensii isolate, which displays some atypical phenotypic characteristics, biochemical profiles, and colony color on selected differential media, and (iv) two nonclinical Enterobacter asburiae isolates, which show some phenotypic characteristics similar to those of Cronobacter spp. The set consists of human (n = 10), food (n = 11), and environmental (n = 9) isolates. Analysis of partial 16S rDNA sequence and seven-gene multilocus sequence typing data allowed for reliable identification of these isolates to species and identification of 14 isolates as sequence type 4, which had previously been shown to be the most common C. sakazakii sequence type associated with neonatal meningitis. Phenotypic characterization was carried out with API 20E and API 32E test strips and streaking on two selective chromogenic agars; isolates were also assessed for sorbitol fermentation and growth at 45°C. Although these strategies typically produced the same classification as sequence-based strategies, based on a panel of four biochemical tests, one C. sakazakii isolate yielded inconclusive data and one was classified as C. malonaticus. EcoRI automated ribotyping and pulsed-field gel electrophoresis (PFGE) with XbaI separated the set into 23 unique ribotypes and 30 unique PFGE types, respectively, indicating subtype diversity within the set. Subtype and source data for the collection are publicly available in the PathogenTracker database (www. pathogentracker. net), which allows for continuous updating of information on the set, including links to publications that include information on isolates from this collection.
Collapse
Affiliation(s)
- Reid A Ivy
- Department of Food Science, Cornell University, Ithaca, New York 14853, USA
| | | | | | | |
Collapse
|
18
|
Song KY, Chon JW, Kim HS, Seo KH. Current Cronobacter spp. Researches on Prevalence, Control, and Detection. ACTA ACUST UNITED AC 2012. [DOI: 10.7845/kjm.2012.051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
19
|
Species of Cronobacter – A review of recent advances in the genus and their significance in infant formula milk. Int Dairy J 2012. [DOI: 10.1016/j.idairyj.2012.06.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
20
|
Giri CP, Shima K, Tall BD, Curtis S, Sathyamoorthy V, Hanisch B, Kim KS, Kopecko DJ. Cronobacter spp. (previously Enterobacter sakazakii) invade and translocate across both cultured human intestinal epithelial cells and human brain microvascular endothelial cells. Microb Pathog 2011; 52:140-7. [PMID: 22023990 DOI: 10.1016/j.micpath.2011.10.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 10/07/2011] [Accepted: 10/10/2011] [Indexed: 12/21/2022]
Abstract
The mechanism of Cronobacter pathogenesis in neonatal meningitis and potential virulence factors (aside from host cell invasion ability) remain largely unknown. To ascertain whether Cronobacter can invade and transcytose across intestinal epithelial cells, enter into the blood stream and then transcytose across the blood-brain-barrier, we have utilized human intestinal INT407 and Caco-2 cells and brain microvascular endothelial cell (HBMEC) monolayers on Transwell filters as experimental model systems. Our data indicate a wide range of heterogeneity with respect to invasion efficiency among twenty-three Cronobacter isolates screened. For selected isolates, we observed significant levels of transcytosis for Cronobacter sakazakii across tight monolayers of both Caco-2 and HBMEC, mimicking in vivo ability to cross the intestine as well as the blood brain barrier, and at a frequency equivalent to that of a control meningitis-causing Escherichia coli K1 strain. Finally, EM analysis demonstrated intracellular Cronobacter bacteria within host vacuoles in HBMEC, as well as transcytosed bacteria at the basolateral surface. These data reveal that certain Cronobacter isolates can invade and translocate across both cultured human intestinal epithelial cells and HBMEC, thus demonstrating a potential path for neonatal infections of the central nervous system (CNS) following oral ingestion.
Collapse
Affiliation(s)
- Chandrakant P Giri
- Laboratory of Enteric and Sexually Transmitted Diseases, DBPAP, OVRR, Center for Biologics Evaluation and Research, Food & Drug Administration, Bethesda, MD 20892, USA.
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Cpa, the outer membrane protease of Cronobacter sakazakii, activates plasminogen and mediates resistance to serum bactericidal activity. Infect Immun 2011; 79:1578-87. [PMID: 21245266 DOI: 10.1128/iai.01165-10] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Cronobacter spp. are emerging neonatal pathogens in humans, associated with outbreaks of meningitis and sepsis. To cause disease, they must survive in blood and invade the central nervous system by penetrating the blood-brain barrier. C. sakazakii BAA-894 possesses an ~131-kb plasmid (pESA3) that encodes an outer membrane protease (Cpa) that has significant identity to proteins that belong to the Pla subfamily of omptins. Members of this subfamily of proteins degrade a number of serum proteins, including circulating complement, providing protection from the complement-dependent serum killing. Moreover, proteins of the Pla subfamily can cause uncontrolled plasmin activity by converting plasminogen to plasmin and inactivating the plasmin inhibitor α2-antiplasmin (α2-AP). These reactions enhance the spread and invasion of bacteria in the host. In this study, we found that an isogenic cpa mutant showed reduced resistance to serum in comparison to its parent C. sakazakii BAA-894 strain. Overexpression of Cpa in C. sakazakii or Escherichia coli DH5α showed that Cpa proteolytically cleaved complement components C3, C3a, and C4b. Furthermore, a strain of C. sakazakii overexpressing Cpa caused a rapid activation of plasminogen and inactivation of α2-AP. These results strongly suggest that Cpa may be an important virulence factor involved in serum resistance, as well as in the spread and invasion of C. sakazakii.
Collapse
|
22
|
Healy B, Cooney S, O'Brien S, Iversen C, Whyte P, Nally J, Callanan JJ, Fanning S. Cronobacter (Enterobacter sakazakii): an opportunistic foodborne pathogen. Foodborne Pathog Dis 2010; 7:339-50. [PMID: 19958103 DOI: 10.1089/fpd.2009.0379] [Citation(s) in RCA: 196] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Cronobacter spp. (Enterobacter sakazakii) are a recently described genus that is comprised of six genomospecies. The classification of these organisms was revised based on a detailed polyphasic taxonomic study. Cronobacter spp. are regarded as ubiquitous organisms having been isolated from a wide variety of foods. These bacteria are opportunistic pathogens and are linked with life-threatening infections in neonates. Clinical symptoms of Cronobacter infection include necrotizing enterocolitis, bacteremia, and meningitis, with case fatality rates of 50-80% being reported. Contaminated powdered infant formula has been epidemiologically linked with infections. Recently, infections among immunocompromised adults, mainly the elderly, have also been reported. A high tolerance to osmotic stress and elevated temperatures contribute to the survival of Cronobacter spp. in dried foods such as powdered infant formula. Controlling the organism in the production environment, thereby reducing dissemination, necessitates the provision of suitable diagnostic tools. Studies demonstrated that a high degree of variability exists amongst the phenotypic-based methods used to identify Cronobacter spp. However, advances in molecular detection and subtyping techniques have significantly improved the identification and characterization of Cronobacter spp. The dose required to induce infection has yet to be determined. In vitro virulence studies have shown that Cronobacter spp. may survive in macrophage cells and efficiently attach to and invade epithelial cell lines. The production of exopolysaccharide may contribute to the formation of biofilm and active efflux pumps promote resistance to antimicrobial agents such as bile salts and disinfectants. A holistic approach combining techniques such as comparative genome analysis, proteomics, and in vivo challenges could help unravel the complex interactions between this pathogen and its host. These data would help identify those properties in Cronobacter spp. which enable the bacterium to survive in the production environment and infect vulnerable neonates via the food chain.
Collapse
Affiliation(s)
- Brendan Healy
- Centres for Food Safety and Foodborne Zoonomics, School of Agriculture, Food Science, and Veterinary Medicine, University College Dublin, Belfield, Dublin, Ireland
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Abstract
Species of the Cronobacter genus ("Enterobacter sakazakii" s. l.) are emergent food-borne pathogens that can cause rare but severe neonatal meningitis, bacteriaemia, and necrotizing enterocolitis. Preterm, low-birth-weight, and immuno-compromised infants exposed to these bacterial species are at particular risk. Over the last 50 years, the literature has reported, mainly in newborn children, more than one hundred cases of infection due to these pathogens. The objective of this review was to synthesize the recent advances in knowledge of species of the Cronobacter genus, in particular with regards to taxonomy, physiology, pathogenicity, clinical cases, the methods for detection, isolation, and characterization, and their presence in powdered formulae for infants and young children, which were identified as the main infection vector. Researchers and international public health authorities have explored the ways contamination occur to better control the risks of pathogen development. Appropriate analysis and control measures were implemented in areas processing powdered formulae for infants and young children, and caregivers and families were informed to undertake good hygienic practices.
Collapse
Affiliation(s)
- Isabelle Proudy
- Service de microbiologie, Equipe d'accueil 2128, Centre hospitalier universitaire, Université de Caen Basse-Normandie, avenue Côte de Nacre, Caen CEDEX, France.
| |
Collapse
|
24
|
Carranza P, Hartmann I, Lehner A, Stephan R, Gehrig P, Grossmann J, Barkow-Oesterreicher S, Roschitzki B, Eberl L, Riedel K. Proteomic profiling of Cronobacter turicensis
3032, a food-borne opportunistic pathogen. Proteomics 2009; 9:3564-79. [DOI: 10.1002/pmic.200900016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|