1
|
Lee JY, Kwon EA, Kim SS. Inactivation of Cronobacter sakazakii in powdered infant formula with probiotics and metagenomic analysis. Food Sci Biotechnol 2024; 33:1985-1996. [PMID: 38752114 PMCID: PMC11091003 DOI: 10.1007/s10068-023-01503-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/22/2023] [Accepted: 12/11/2023] [Indexed: 05/18/2024] Open
Abstract
In the present study, proper manual for powdered infant formula with probiotics (PIF-P) to prevent the contamination of Cronobacter sakazakii was investigated. First, the population of C. sakazakii and LAB in three different PIF-P samples were quantitatively analyzed after reconstituted with hydrothermal treatments. When C. sakazakii was inoculated into reconstituted infant formula with probiotics (RIF-P), it was immediately reduced below the detection limit by 60-65 °C hydrothermal treatment whereas reduction levels of LAB was 1-2 log CFU/g. When heat resistance of C. sakazakii inoculated to PIF-P with 4 h drying was compared with that inoculated to RIF-P samples, the heat resistance of C. sakazakii increased significantly after the inoculation in PIF-P with drying. Metagenomic analysis revealed that Lactobacillus and Bifidobacterium were dominant genus in all three groups and there was no significant difference in the microbial community of untreated PIF sample and hydrothermal treated samples. Supplementary Information The online version contains supplementary material available at 10.1007/s10068-023-01503-x.
Collapse
Affiliation(s)
- Ji-Yeon Lee
- Department of Food Engineering, Dankook University, Cheonan, Chungnam 31116 Republic of Korea
| | - Eun-Ae Kwon
- Department of Food Engineering, Dankook University, Cheonan, Chungnam 31116 Republic of Korea
| | - Sang-Soon Kim
- Department of Food Engineering, Dankook University, Cheonan, Chungnam 31116 Republic of Korea
| |
Collapse
|
2
|
Wang Y, Ling N, Jiao R, Zhang X, Ren Y, Zhao W, Chen H, Ye Y. A universal mechanism on desiccation tolerance of Cronobacter based on intracellular trehalose accumulation regulated by EnvZ/OmpR. Food Microbiol 2024; 119:104455. [PMID: 38225055 DOI: 10.1016/j.fm.2023.104455] [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: 06/13/2023] [Revised: 12/04/2023] [Accepted: 12/20/2023] [Indexed: 01/17/2024]
Abstract
Cronobacter (seven species) can survive in dry powdered infant formula for a long time, but the thorough molecular mechanism of resistance to desiccation remains elusive. Here we examine the regulation mechanism of Cronobacter's tolerance to desiccation by the typical two-component system (TCS) EnvZ/OmpR. When exposed to desiccation conditions, Cronobacter showed higher survival than other pathogens, as well as significantly up-regulated expression of ompR and otsAB genes with markedly decreased survival of their mutants, suggesting their relationship with desiccation tolerance. OmpR directly binds to the promoter of trehalose biosynthesis operon otsBA, significantly enhancing their expression, and boosting the trehalose levels. The ompR-deletion in other six species further confirmed its positive regulation in desiccation tolerance. Our data present a hypothesis that EnvZ/OmpR increases intracellular trehalose levels against damage to the cells, which prompts Cronobacter to survive in desiccation conditions. This study reveals a universal molecular mechanism for desiccation resistance in Cronobacter species.
Collapse
Affiliation(s)
- Yang Wang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Na Ling
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Rui Jiao
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Xiyan Zhang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Yuwei Ren
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Wenhua Zhao
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Hanfang Chen
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Yingwang Ye
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China; State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, China.
| |
Collapse
|
3
|
Kireina D, Parreira VR, Goodridge L, Farber JM. Survival and Expression of rpoS and grxB of Cronobacter sakazakii in Powdered Infant Formula Under Simulated Gastric Conditions of Newborns. J Food Prot 2024; 87:100269. [PMID: 38519033 DOI: 10.1016/j.jfp.2024.100269] [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: 10/31/2023] [Revised: 03/15/2024] [Accepted: 03/18/2024] [Indexed: 03/24/2024]
Abstract
Cronobacter sakazakii can cause severe illnesses in infants, predominantly in preterm newborns, with consumption of contaminated powdered infant formula (PIF) being the major vehicle of infection. Using a dynamic human gastrointestinal simulator called the SHIME, this study examined the effects of gastric acidity and gastric digestion time of newborns on the survival and expression of stress genes of C. sakazakii. Individual strains, inoculated at 7 log CFU/mL into reconstituted PIF, were exposed to gastric pH values of 4.00, 5.00 and 6.00 for 4 h with gradual acidification. The survival results showed that C. sakazakii grew in the stomach portion of the SHIME during a 4-h exposure to pH 4.00, 5.00 and 6.00 by 0.96-1.05, 1.02-1.28 and 1.11-1.73 log CFU/mL, respectively. The expression of two stress genes, rpoS and grxB, throughout gastric digestion was evaluated using reverse transcription qPCR. The upregulation of rpoS and grxB during the 4-h exposure to simulated gastric fluid at pH 4.00 showed that C. sakazakii strains may be experiencing the most stress in the pH 4.00 treatment. The gene expression results also suggest that C. sakazakii strains appeared to develop an acid adaptation response during the 4-h exposure that may facilitate their survival. Altogether, this study highlights that a combination of low gastric acidity, long digestion time in the presence of reconstituted PIF, created a favorable environment for the adaptation and survival of C. sakazakii in the simulation of a newborn's stomach. This study gives directions for future research to further advance our understanding of the behavior of C. sakazakii in the GI tract of newborns.
Collapse
Affiliation(s)
- Devita Kireina
- Canadian Research Institute for Food Safety, Department of Food Science, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Valeria R Parreira
- Canadian Research Institute for Food Safety, Department of Food Science, University of Guelph, Guelph, ON N1G 2W1, Canada.
| | - Lawrence Goodridge
- Canadian Research Institute for Food Safety, Department of Food Science, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Jeffrey M Farber
- Canadian Research Institute for Food Safety, Department of Food Science, University of Guelph, Guelph, ON N1G 2W1, Canada
| |
Collapse
|
4
|
Chen X, Zheng X, Fan C, Song Q, Tian Z, Huang D, Li Y, Meng F, Chang Y, Wei X, Fei P. Antibacterial Pattern of Rosa roxburghii Tratt Pomace Crude Extract Against Staphylococcus aureus and Its Application in Preservation of Cooked Beef. Foodborne Pathog Dis 2023; 20:110-119. [PMID: 36893329 DOI: 10.1089/fpd.2022.0082] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023] Open
Abstract
Staphylococcus aureus is a common foodborne pathogen and spoilage bacterium in meat products. To develop a natural preservative for meat products, this study revealed the antibacterial activity and mechanism of Rosa roxburghii Tratt pomace crude extract (RRPCE) against S. aureus, and applied RRPCE to the preservation of cooked beef. The diameter of inhibition zone, minimum inhibitory concentration (MIC), and minimum bactericide concentration of RRPCE against S. aureus were 15.85 ± 0.35 to 16.21 ± 0.29 mm, 1.5 mg/mL, and 3 mg/mL, respectively. The growth curve of S. aureus was completely stalled by treatment with RRPCE at 2 MIC. RRPCE results in the decrease of intracellular adenosine 5'-triphosphate (ATP) content, depolarization of cell membrane, leakage of cell fluid including nucleic acid and protein, and destruction of cell membrane integrity and cell morphology. During storage, RRPCE significantly reduced S. aureus viable counts, pH, and total volatile basic nitrogen of cooked beef compared with untreated samples (p < 0.05). In addition, RRPCE could significantly increase the redness (a*) value, decrease lightness (L*) and yellowness (b*) values, and slow down the color change of cooked beef (p < 0.05). These findings suggest that RRPCE can effectively inhibit S. aureus, and has the potential as a natural preservative for the preservation of cooked beef.
Collapse
Affiliation(s)
- Xi Chen
- Institute of Integrated Agricultural Development Research, Guizhou Academy of Agricultural Sciences, Guiyang, China
| | - Xiuyan Zheng
- Institute of Integrated Agricultural Development Research, Guizhou Academy of Agricultural Sciences, Guiyang, China
| | - Chengwei Fan
- School of Zhang Zhongjing Health Care and Food, Nanyang Institute of Technology, Nanyang, China
| | - Qianhua Song
- School of Zhang Zhongjing Health Care and Food, Nanyang Institute of Technology, Nanyang, China
| | - Zhuxi Tian
- Institute of Integrated Agricultural Development Research, Guizhou Academy of Agricultural Sciences, Guiyang, China
| | - Daomei Huang
- Institute of Integrated Agricultural Development Research, Guizhou Academy of Agricultural Sciences, Guiyang, China
| | - Yongfu Li
- Institute of Integrated Agricultural Development Research, Guizhou Academy of Agricultural Sciences, Guiyang, China
| | - Fanbo Meng
- Institute of Integrated Agricultural Development Research, Guizhou Academy of Agricultural Sciences, Guiyang, China
| | - Yunhe Chang
- Food and Pharmaceutical Engineering Institute, Guiyang University, Guiyang, China
| | - Xiaoping Wei
- Institute of Integrated Agricultural Development Research, Guizhou Academy of Agricultural Sciences, Guiyang, China
| | - Peng Fei
- School of Zhang Zhongjing Health Care and Food, Nanyang Institute of Technology, Nanyang, China
| |
Collapse
|
5
|
Integrative Multiomics Analysis of the Heat Stress Response of Enterococcus faecium. Biomolecules 2023; 13:biom13030437. [PMID: 36979372 PMCID: PMC10046512 DOI: 10.3390/biom13030437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/20/2023] [Accepted: 02/22/2023] [Indexed: 03/02/2023] Open
Abstract
A continuous heat-adaptation test was conducted for one Enterococcus faecium (E. faecium) strain wild-type (WT) RS047 to obtain a high-temperature-resistant strain. After domestication, the strain was screened with a significantly higher ability of heat resistance. which is named RS047-wl. Then a multi-omics analysis of transcriptomics and metabolomics was used to analyze the mechanism of the heat resistance of the mutant. A total of 98 differentially expressed genes (DEGs) and 115 differential metabolites covering multiple metabolic processes were detected in the mutant, which indicated that the tolerance of heat resistance was regulated by multiple mechanisms. The changes in AgrB, AgrC, and AgrA gene expressions were involved in quorum-sensing (QS) system pathways, which regulate biofilm formation. Second, highly soluble osmotic substances such as putrescine, spermidine, glycine betaine (GB), and trehalose-6P were accumulated for the membrane transport system. Third, organic acids metabolism and purine metabolism were down-regulated. The findings can provide target genes for subsequent genetic modification of E. faecium, and provide indications for screening heat-resistant bacteria, so as to improve the heat-resistant ability of E. faecium for production.
Collapse
|
6
|
Cheng R, Li X, Jiang L, Gong L, Geslin C, Shao Z. Virus diversity and interactions with hosts in deep-sea hydrothermal vents. MICROBIOME 2022; 10:235. [PMID: 36566239 PMCID: PMC9789665 DOI: 10.1186/s40168-022-01441-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND The deep sea harbors many viruses, yet their diversity and interactions with hosts in hydrothermal ecosystems are largely unknown. Here, we analyzed the viral composition, distribution, host preference, and metabolic potential in different habitats of global hydrothermal vents, including vent plumes, background seawater, diffuse fluids, and sediments. RESULTS From 34 samples collected at eight vent sites, a total of 4662 viral populations (vOTUs) were recovered from the metagenome assemblies, encompassing diverse phylogenetic groups and defining many novel lineages. Apart from the abundant unclassified viruses, tailed phages are most predominant across the global hydrothermal vents, while single-stranded DNA viruses, including Microviridae and small eukaryotic viruses, also constitute a significant part of the viromes. As revealed by protein-sharing network analysis, hydrothermal vent viruses formed many novel genus-level viral clusters and are highly endemic to specific vent sites and habitat types. Only 11% of the vOTUs can be linked to hosts, which are the key microbial taxa of hydrothermal habitats, such as Gammaproteobacteria and Campylobacterota. Intriguingly, vent viromes share some common metabolic features in that they encode auxiliary genes that are extensively involved in the metabolism of carbohydrates, amino acids, cofactors, and vitamins. Specifically, in plume viruses, various auxiliary genes related to methane, nitrogen, and sulfur metabolism were observed, indicating their contribution to host energy conservation. Moreover, the prevalence of sulfur-relay pathway genes indicated the significant role of vent viruses in stabilizing the tRNA structure, which promotes host adaptation to steep environmental gradients. CONCLUSIONS The deep-sea hydrothermal systems hold untapped viral diversity with novelty. They may affect both vent prokaryotic and eukaryotic communities and modulate host metabolism related to vent adaptability. More explorations are needed to depict global vent virus diversity and its roles in this unique ecosystem. Video Abstract.
Collapse
Affiliation(s)
- Ruolin Cheng
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, China
- State Key Laboratory Breeding Base of Marine Genetic Resource, Fujian Key Laboratory of Marine Genetic Resources, Xiamen, 361005, China
| | - Xiaofeng Li
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, China
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China
| | - Lijing Jiang
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, China
| | - Linfeng Gong
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, China
| | - Claire Geslin
- Univ Brest, CNRS, IFREMER, IRP 1211 MicrobSea, Laboratoire de Microbiologie des Environnements Extrêmes LM2E, IUEM, Rue Dumont d'Urville, F-29280, Plouzané, France
- Sino-French Laboratory of Deep-Sea Microbiology (MICROBSEA-LIA), Plouzané, France
| | - Zongze Shao
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, China.
- Sino-French Laboratory of Deep-Sea Microbiology (MICROBSEA-LIA), Plouzané, France.
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519000, China.
| |
Collapse
|
7
|
da Silva MR, Alves de Almeida F, Coelho AÍM, da Silva FL, Vanetti MCD. Enhancing cell resistance for production of mixed microbiological reference materials with Salmonella and coliforms by freeze-drying. Braz J Microbiol 2022; 53:2107-2119. [PMID: 35962856 PMCID: PMC9679061 DOI: 10.1007/s42770-022-00808-z] [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: 02/08/2022] [Accepted: 07/29/2022] [Indexed: 01/13/2023] Open
Abstract
The reference material (RM) is a technical requirement for the quality assurance of analytical results and proficiency tests or interlaboratory comparisons. Microbiological RMs are most available in the dehydrated form, mainly by freeze-drying, and maintaining bacterial survival after preparation is a challenge. Thus, obtaining the most resistant cells is essential. Considering that bacteria present cross-response to dehydration after being submitted to an array of stress conditions, this study aimed to evaluate the influence of growth conditions on enterobacteria for the production of mixed microbiological RMs by freeze-drying in skim milk powder. Salmonella enterica serovar Enteritidis, Cronobacter sakazakii, Escherichia coli, and Citrobacter freundii were grown in a minimal medium with 0.5 M NaCl and 0 to 5.0 mM of manganese sulfate (MnSO4) until stationary phase. Salmonella Enteritidis presented an increased resistance to dehydration in the presence of Mn, while C. sakazakii was the most resistant to freeze-drying and further storage for 90 days. Mixed microbiological RMs were produced by freeze-drying and containing Salmonella Enteritidis and coliforms in skim milk powder with 100 mM of trehalose and the Salmonella survival rate was 91.2 to 93.6%. The mixed RM was stable after 30 days at -20 °C, and Salmonella and coliforms were detected by different methods being, the Rambach Agar the best for the bacterial differentiation. The results showed that the culture conditions applied in this study resulted in bacterial cells being more resistant to dehydration, freeze-drying, and stabilization for the production of mixed microbiological RMs more stable and homogeneous.
Collapse
Affiliation(s)
- Maria Roméria da Silva
- Department of Microbiology, Universidade Federal de Viçosa, Viçosa, MG, 36570-900, Brazil
- Department of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Viçosa, MG, 36570-900, Brazil
| | - Felipe Alves de Almeida
- Department of Nutrition, Universidade Federal de Juiz de Fora, Governador Valadares, MG, 35032-620, Brazil
| | | | - Fernanda Lopes da Silva
- Department of Food Technology, Universidade Federal de Viçosa, Viçosa, MG, 36570-900, Brazil
| | | |
Collapse
|
8
|
Gao Z, Ge C, Baker RC, Tikekar RV, Buchanan RL. Enhancement of Thermal Inactivation of Cronobacter sakazakii in Apple Juice at 58°C by Inclusion of Butyl Para-Hydroxybenzoate and Malic Acid. J Food Prot 2022; 85:1515-1521. [PMID: 35960953 DOI: 10.4315/jfp-22-039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 07/30/2022] [Indexed: 11/11/2022]
Abstract
ABSTRACT After studies with powdered infant formula indicated that the enhancement of thermal inactivation of Cronobacter sakazakii by butyl para-hydroxybenzoate (BPB) was blocked by high protein concentrations, we hypothesized that BPB would retain its synergistic activity in foods with limited protein and lipid concentrations. This hypothesis was tested by examining the ability of BPB to enhance the thermal inactivation of C. sakazakii 607 at 58°C in commercial apple juice, including examining the effects of pH and possible synergistic effects with malic acid. Apple juice was adjusted to designated pH values of 3.2 to 9.0, supplemented with selected concentrations of BPB (≤125 ppm), inoculated with early-stationary-phase C. sakazakii 607, and thermally treated (58°C) for 15 min with a submerged coil apparatus. The same methods were used to study the enhancement of thermal inactivation by malic acid. Samples were plated on tryptic soy agar for recovery and enumeration. Survival curves were plotted, and D-values were calculated by linear regression and compared using the Tukey honestly significant difference test. BPB significantly enhanced thermal inactivation in a concentration dependent manner, with D-values of a few seconds at the original pH (3.8). The enhancement of thermal inactivation was pH dependent over the pH range of 3.4 to 9.0. Malic acid enhanced thermal inactivation; the pH was decreased from 3.8 to 3.2. These results support the hypothesis that BPB can enhance the thermal inactivation of C. sakazakii in low-protein and low-lipid foods. HIGHLIGHTS
Collapse
Affiliation(s)
- Zhujun Gao
- Department of Nutrition and Food Science, People's Republic of China
| | - Chongtao Ge
- Mars Global Food Safety Center, Beijing 101047, People's Republic of China
| | - Robert C Baker
- Mars Global Food Safety Center, Beijing 101047, People's Republic of China
| | - Rohan V Tikekar
- Department of Nutrition and Food Science, People's Republic of China
| | - Robert L Buchanan
- Department of Nutrition and Food Science, People's Republic of China.,Center for Food Safety and Security Systems, University of Maryland, College Park, Maryland 20742, USA
| |
Collapse
|
9
|
Insights into the mechanisms of Cronobacter sakazakii virulence. Microb Pathog 2022; 169:105643. [PMID: 35716925 DOI: 10.1016/j.micpath.2022.105643] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 06/08/2022] [Accepted: 06/12/2022] [Indexed: 10/18/2022]
Abstract
Cronobacter species have adapted to survive harsh conditions, particularly in the food manufacture environment, and can cause life-threatening infections in susceptible hosts. These opportunistic pathogens employ a multitude of mechanisms to aid their virulence throughout three key stages: environmental persistence, infection strategy, and systemic persistence in the human host. Environmental persistence is aided by the formation of biofilms, development of subpopulations, and high tolerance to environmental stressors. Successful infection in the human host involves several mechanisms such as protein secretion, motility, quorum sensing, colonisation, and translocation. Survival inside the host is achieved via competitive acquisition and utilization of minerals and metabolites respectively, coupled with host immune system evasion and antimicrobial resistance (AMR) mechanisms. Across the globe, Cronobacter sakazakii is associated with often fatal systemic infections in populations including neonates, infants, the elderly and the immunocompromised. By providing insight into the mechanisms of virulence utilised by this pathogen across these three stages, this review identifies current gaps in the literature. Further research into these virulence mechanisms is required to inform novel mitigation measures to improve global food safety with regards to this food-borne pathogen.
Collapse
|
10
|
Heat shock in Cronobacter sakazakii induces direct protection and cross-protection against simulated gastric fluid stress. Food Microbiol 2022; 103:103948. [DOI: 10.1016/j.fm.2021.103948] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 11/10/2021] [Accepted: 11/13/2021] [Indexed: 11/21/2022]
|
11
|
Zhan J, Qiao J, Wang X. Role of sigma factor RpoS in Cronobacter sakazakii environmental stress tolerance. Bioengineered 2021; 12:2791-2809. [PMID: 34157953 PMCID: PMC8806803 DOI: 10.1080/21655979.2021.1938499] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 05/31/2021] [Indexed: 11/12/2022] Open
Abstract
Cronobacter sakazakii is a food-borne, conditionally pathogenic bacterium that mainly infects neonates, especially premature infants. Previous studies have indicated that an important route of infection for C. sakazakii is through infant formula, suggesting a high stress resistance of the bacterium. RpoS is a σ-factor that is closely related to the bacterial resistance mechanisms. In this study, a C. sakazakii BAA894 model strain was used. An rpoS-deficient mutant strain Δrpos was constructed using Red homologous recombination, and the differences between the mutant and the wild-type strains were compared. To investigate the functions of the rpoS gene, the membrane formation and cell wall properties of the strains were studied, and the tolerance of each strain to acid, osmotic pressure, desiccation, and drug resistance were compared. The results showed that the membrane formation ability in the mutant strain was increased, auto-aggregation was enhanced, motility, acid resistance and hyperosmotic resistance were alternated to different degrees, and desiccation resistance was stronger than observed in the wild type grown in LB medium but weaker than the wild type cultured in M9 medium. These results showed that rpoS is involved in environmental stress resistance in C. sakazakii BAA894. Finally, transcriptome analysis verified that the deletion of the rpoS gene caused differential expression of resistance-related genes and instigated changes in related metabolic pathways. These messenger RNA results were consistent with the functional experimental results and help explain the phenotypic changes observed in the mutant strain.
Collapse
Affiliation(s)
- Jie Zhan
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- School of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Jun Qiao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Xiaoyuan Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- School of Food Science and Technology, Jiangnan University, Wuxi, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| |
Collapse
|
12
|
Alterations in the Transcriptional Landscape Allow Differential Desiccation Tolerance in Clinical Cronobacter sakazakii. Appl Environ Microbiol 2021; 87:e0083021. [PMID: 34644165 DOI: 10.1128/aem.00830-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cronobacter sakazakii is a typical example of a xerotolerant bacterium. It is epidemiologically linked to low-moisture foods like powdered infant formula (PIF) and is associated with high fatality rates among neonates. We characterized the xerotolerance in a clinically isolated strain, Cronobacter sakazakii ATCC™29544T, and compared the desiccation tolerance with that of an environmental strain, C. sakazakii SP291, whose desiccation tolerance was previously characterized. We found that, although the clinical strain was desiccation-tolerant, the level of tolerance was compromised when compared with that of the environmental strain. Transcriptome sequencing (RNA-seq)-based deep transcriptomic characterization identified a unique transcriptional profile in the clinical strain compared with what was already known for the environmental strain. As RNA-seq was also carried out under different TSB growth conditions, genes that were expressed specifically under desiccated conditions were identified and denoted as desiccation responsive genes (DRGs). Interestingly, these DRGs included transcriptomic factors like fnr, ramA, and genes associated with inositol metabolism, a phenotype as yet unreported in C. sakazakii. Further, the clinical strain did not express the proP gene, which was previously reported to be very important for desiccation survival and persistence. Interestingly, analysis of the plasmid genes showed that the iron metabolism in desiccated C. sakazakii ATCC™29544T cells specifically involved the siderophore cronobactin, encoded by the iucABCD genes. Confirmatory studies using quantitative reverse transcription-PCR (qRT-PCR) determined that, though the secondary desiccation response genes were upregulated in C. sakazakii ATCC™29544T, the level of upregulation was lower than that in C. sakazakii SP291. All these factors may collectively contribute to the compromised desiccation tolerance in the clinical strain. IMPORTANCE Cronobacter sakazakii has led to outbreaks in the past, particularly associated with foods that are low in moisture content. This species has adapted to survive in low water conditions and can survive in such environments for long periods. These characteristics have enabled the pathogen to contaminate powder infant formula, a food matrix with which the pathogen has been epidemiologically associated. Even though clinically adapted strains can also be isolated, there is no information on how the clinical strains adapt to low moisture environments. Our research assessed the adaptation of a clinically isolated strain to low moisture survival on sterile stainless steel coupons and compared the survival with that of a highly desiccation-tolerant environmental strain. We found that, even though the clinical strain is desiccation-tolerant, the rate of tolerance was compromised compared with that of the environmental strain. A deeper investigation using RNA-seq identified that the clinical strain used pathways different from that of the environmental strain to adapt to low-moisture conditions. This shows that the adaptation to desiccation conditions, at least for C. sakazakii, is strain-specific and that different strains have used different evolutionary strategies for adaptation.
Collapse
|
13
|
Zhan J, Tan X, Wang X. Null mutation in sspA of Cronobacter sakazakii influences its tolerance to environmental stress. Can J Microbiol 2021; 67:902-918. [PMID: 34379995 DOI: 10.1139/cjm-2021-0114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cronobacter sakazakii is a known foodborne opportunistic pathogen that can affect the intestinal health of infants. Despite undergoing complex manufacturing processes and low water concentration in the finished product, infant formula has been associated with Cronobacter infections, suggesting that C. sakazakii's pathogenicity may be related to its tolerance to stress. In this study, the effect of the stringent starvation protein A (SspA), which plays an important role in E. coli cellular survival under environmental stresses, on the stress tolerance of C. sakazakii BAA894 was investigated by creating an sspA-knockout mutant. The effects of this mutation on the acid, desiccation and drug tolerance were assessed, and results showed that acid tolerance decreased, while desiccation tolerance increased in LB and decreased in M9. Moreover, the MICs of 10 antibiotics in LB medium and 8 antibiotics in M9 medium were determined and compared of the wild-type and ΔsspA. Transcriptome analysis showed that 27.21% or 37.78% of the genes in ΔsspA were significantly differentially expressed in LB or M9 media, the genes relevant to microbial metabolism in diverse environments and bacterial chemotaxis were detailed analyzed. The current study contributes towards an improved understanding of the role of SspA in C. sakazakii BAA894 stress tolerance.
Collapse
Affiliation(s)
- Jie Zhan
- Jiangnan University, 66374, State Key Laboratory of Food Science and Technology, Wuxi, China;
| | - Xin Tan
- Jiangnan University, 66374, Wuxi, China.,Jiangnan University, 66374, Wuxi, China;
| | - Xiaoyuan Wang
- Jiangnan University, 66374, Wuxi, China, 214122.,Jiangnan University, 66374, Wuxi, China, 214122.,Jiangnan University, 66374, Wuxi, China, 214122;
| |
Collapse
|
14
|
Wang L, Forsythe SJ, Yang X, Fu S, Man C, Jiang Y. Invited review: Stress resistance of Cronobacter spp. affecting control of its growth during food production. J Dairy Sci 2021; 104:11348-11367. [PMID: 34364644 DOI: 10.3168/jds.2021-20591] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 06/17/2021] [Indexed: 11/19/2022]
Abstract
Members of the Cronobacter genus include food-borne pathogens that can cause infections in infants, with a mortality rate as high as 40 to 80%. The high fatality rate of Cronobacter and its isolation from numerous types of food, especially from powdered infant formula, demonstrate the serious nature of this organism. The source tracking of Cronobacter spp. and the analysis of high-frequency species from different sources are helpful for a more targeted control. Furthermore, the persistence during food processing and storage may be attributed to strong resistance of Cronobacter spp. to environment stresses such as heat, pH, and desiccation. There are many factors that support the survival of Cronobacter spp. in harsh environments, such as some genes, regulatory systems, and biofilms. Advanced detection technology is helpful for the strict monitoring of Cronobacter spp. In addition to the traditional heat treatment, many new control techniques have been developed, and the ability to control Cronobacter spp. has been demonstrated. The control of this bacteria is required not only during manufacture, but also through the selection of packaging methods to reduce postprocessing contamination. At the same time, the effect of inactivation methods on product quality and safety must be considered. This review considers the advances in our understanding of environmental stress response in Cronobacter spp. with special emphasis on its implications in food processing.
Collapse
Affiliation(s)
- Lihan Wang
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural University, Harbin, China, 150030
| | - Stephen J Forsythe
- Foodmicrobe.com, Adams Hill, Keyworth, Nottingham, United Kingdom, NG12 5GY
| | - Xinyan Yang
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural University, Harbin, China, 150030
| | - Shiqian Fu
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural University, Harbin, China, 150030
| | - Chaoxin Man
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural University, Harbin, China, 150030.
| | - Yujun Jiang
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural University, Harbin, China, 150030.
| |
Collapse
|
15
|
Antoine L, Bahena-Ceron R, Devi Bunwaree H, Gobry M, Loegler V, Romby P, Marzi S. RNA Modifications in Pathogenic Bacteria: Impact on Host Adaptation and Virulence. Genes (Basel) 2021; 12:1125. [PMID: 34440299 PMCID: PMC8394870 DOI: 10.3390/genes12081125] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/16/2021] [Accepted: 07/19/2021] [Indexed: 12/19/2022] Open
Abstract
RNA modifications are involved in numerous biological processes and are present in all RNA classes. These modifications can be constitutive or modulated in response to adaptive processes. RNA modifications play multiple functions since they can impact RNA base-pairings, recognition by proteins, decoding, as well as RNA structure and stability. However, their roles in stress, environmental adaptation and during infections caused by pathogenic bacteria have just started to be appreciated. With the development of modern technologies in mass spectrometry and deep sequencing, recent examples of modifications regulating host-pathogen interactions have been demonstrated. They show how RNA modifications can regulate immune responses, antibiotic resistance, expression of virulence genes, and bacterial persistence. Here, we illustrate some of these findings, and highlight the strategies used to characterize RNA modifications, and their potential for new therapeutic applications.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Stefano Marzi
- Université de Strasbourg, CNRS, Architecture et Réactivité de l’ARN, UPR 9002, F-67000 Strasbourg, France; (L.A.); (R.B.-C.); (H.D.B.); (M.G.); (V.L.); (P.R.)
| |
Collapse
|
16
|
Ling N, Ou D, Shen Y, Zhang D, Wang Y, Tong L, Ding Y, Wang J, Yang X, Zhang J, Wu Q, Ye Y. Proteomics analysis mediated by quorum sensing luxS involved in oxidative stress in Cronobacter malonaticus. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.111576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
17
|
Qin X, Wang H, Miao C, Yang X, Zhang Y, Feng J, Forsythe SJ, Man C, Jiang Y. Comparative genomics reveals environmental adaptation differences between Cronobacter species. Food Res Int 2021; 147:110541. [PMID: 34399518 DOI: 10.1016/j.foodres.2021.110541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 06/13/2021] [Accepted: 06/15/2021] [Indexed: 10/21/2022]
Abstract
The genus Cronobacter is an opportunistic food-borne pathogen which is able to adapt to diverse environments and shows considerable genetic diversity. Genomic analysis can be used to reveal the variation across the genus with respect to virulence, drug resistance and factors involved in horizontal gene transfer mechanisms, such as integrons, conjugative plasmids, and recombinases. In this study, whole-genome comparative analysis of 27 Cronobacter genomes (12 existing and 15 newly assembled genomes) was performed. A total of 110,010 protein-coding genes were grouped into 11,262 clusters, including 2637 core genes, 4814 strain-specific genes and 3811 dispensable genes. Clusters of Orthologous Groups (COG) analysis indicated that 97.35% of the core genes were for substrate transport and metabolism, and the antibiotic resistance genetic determinants were classified into 136 antibiotic resistance ontologies (AROs). A total of 80 genomic islands (GIs) were identified which contained several type VI secretion system gene clusters, and these were likely to have been acquired by horizontal gene transfer. This study has generated a comprehensive characterization of the genus Cronobacter, leading to a better understanding of the mechanisms and ecological functions among the genome features, speciation, and environmental adaptation strategies.
Collapse
Affiliation(s)
- Xue Qin
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science and Engineering, Northeast Agricultural University, Harbin 150030, China
| | - Hao Wang
- College of Life Science, Northeast Agricultural University, Harbin, China
| | - Chao Miao
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science and Engineering, Northeast Agricultural University, Harbin 150030, China
| | - Xinyan Yang
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science and Engineering, Northeast Agricultural University, Harbin 150030, China
| | - Yanming Zhang
- SinoGenoMax Co., Ltd./Chinese National Human Genome Center, Beijing 100176, China
| | - Jing Feng
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science and Engineering, Northeast Agricultural University, Harbin 150030, China
| | | | - Chaoxin Man
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science and Engineering, Northeast Agricultural University, Harbin 150030, China.
| | - Yujun Jiang
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science and Engineering, Northeast Agricultural University, Harbin 150030, China.
| |
Collapse
|
18
|
Cao Y, Li L, Zhang Y, Liu F, Xiao X, Li X, Yu Y. SdiA plays a crucial role in stress tolerance of C. sakazakii CICC 21544. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.111189] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
19
|
Zheng Z, Xie Y, Ma S, Tu J, Li J, Liang S, Xu Y, Shi C. Effect of 405-nm light-emitting diode on environmental tolerance of Cronobacter sakazakii in powdered infant formula. Food Res Int 2021; 144:110343. [PMID: 34053539 DOI: 10.1016/j.foodres.2021.110343] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 03/17/2021] [Accepted: 03/18/2021] [Indexed: 02/05/2023]
Abstract
Cronobacter sakazakii is an opportunistic pathogen that can survive extreme desiccation, heat, acid, and osmotic stress. This can increase the risk of infection, resulting in severe diseases, mainly in neonates. The inactivation effect of 405 ± 5-nm light-emitting diode (LED) illumination on C. sakazakii with different initial concentrations and C. sakazakii strains isolated from powdered infant formula (PIF) and baby rice cereal (BRC) were firstly evaluated. Then, the effect of 405 ± 5-nm LED on the tolerance of diverse environmental conditions of C. sakazakii in PIF was investigated. Conditions involving desiccation [PIF, Water activity (aw): 0.2-0.5], heat (45, 50, and 55 °C), acid (simulated gastric fluid: SGF, pH 4.75 ± 0.25), and bile salt (0.2%, bile salt solution) were used to study the effects of 405-nm LED on C. sakazakii resistance. The transcription levels of ten tolerance-associated genes and changes in bacterial cell membrane were examined to understand the response of C. sakazakii to LED illumination. The results showed that 405-nm LED effectively inactivated C. sakazakii ATCC 29544 with initial concentration from 8 to 1 log CFU/g in PIF and strains isolated from PIF and BRC. Moreover, 405-nm LED could decrease the tolerance of C. sakazakii in PIF to desiccation, heat treatment at 50 and 55 °C, SGF, and bile salt to different degrees, but the resistance to the heat treatment at 45 °C was not influenced by LED illumination. In addition, the transcription levels of the ten tolerance-associated genes measured in the LED-illuminated C. sakazakii cells were significantly downregulated compared with those in unilluminated controls. The damage on cell membrane was confirmed for LED-treated cells by LIVE/DEAD® assay. These results indicate that 405-nm LED illumination may be effective at reducing the environmental resistance of C. sakazakii in PIF. Furthermore, this study suggests the potential for applying 405-nm LED technology in the prevention and control of pathogens in food processing, production, and storage environments.
Collapse
Affiliation(s)
- Zhanwen Zheng
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yawen Xie
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Sheng Ma
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Junhong Tu
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jiahui Li
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Sen Liang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, Beijing 100048, China
| | - Yunfeng Xu
- College of Food and Bioengineering, Henan University of Science and Technology, Luoyang, Henan 471023, China
| | - Chao Shi
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China.
| |
Collapse
|
20
|
Ji X, Lu P, Xue J, Zhao N, Zhang Y, Dong L, Zhang X, Li P, Hu Y, Wang J, Zhang B, Liu J, Lv H, Wang S. The lipoprotein NlpD in Cronobacter sakazakii responds to acid stress and regulates macrophage resistance and virulence by maintaining membrane integrity. Virulence 2021; 12:415-429. [PMID: 33459158 PMCID: PMC7834084 DOI: 10.1080/21505594.2020.1870336] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Cronobacter sakazakii, an emerging opportunistic pathogen, is implicated in severe foodborne outbreak infections in premature and full-term infants. Generally, acid tolerance is vital for the pathogenesis of foodborne pathogens; however, its role in C. sakazakii virulence remains largely unknown. To screen out acid-tolerance determinants from transposon mutants, anovel counterselection method using gentamicin and acid was developed. Using the counterselection method and growth assay, we screened several acid-sensitive mutants and found that nlpD encodes an acid-resistance factor in C. sakazakii. Compared to the wild-type strain, the nlpD mutant exhibited attenuated virulence in a rat model. Using macrophage THP-1 cells and a pH probe, we verified that nlpD enables bacteria to resist macrophages by resisting acidification. Finally, we confirmed that nlpD maintains C. sakazakii membrane integrity in acid using propidium iodide permeabilization assays via flow cytometry. Our results confirm that nlpD is a novel virulence factor that permits C. sakazakii to survive under acid stress conditions. Considering that NlpD is a conserved lipoprotein located in the bacterial outer membrane, NlpD could be used as a target for drug development.
Collapse
Affiliation(s)
- Xuemeng Ji
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Ping Lu
- Institute of Radiation Medicine, Chinese Academy of Medical Science and Peking Union Medical Collage , Tianjin, China
| | - Juan Xue
- Institute of Infection and Immunity, Taihe Hospital, Hubei University of Medicine , Shiyan, China
| | - Ning Zhao
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Yan Zhang
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Lu Dong
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Xuejiao Zhang
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Ping Li
- Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology , Tianjin, China
| | - Yaozhong Hu
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Jin Wang
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Bowei Zhang
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Jingmin Liu
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Huan Lv
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Shuo Wang
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| |
Collapse
|
21
|
Veronica EK, Sara A O, Everardo CQ, Héctor Q, Oscar MC, Elizabeth FR, Irma RP, José AG, Bulmaro C, Rigoberto HC, Juan XC, Ariadnna CC. Proteomics profiles of Cronobacter sakazakii and a fliF mutant: Adherence and invasion in mouse neuroblastoma cells. Microb Pathog 2020; 149:104595. [PMID: 33157215 DOI: 10.1016/j.micpath.2020.104595] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 01/17/2023]
Abstract
Cronobacter sakazakii is an opportunistic foodborne pathogen associated with necrotizing enterocolitis, bacteremia, and meningitis in infants. A comparative proteomic study of C. sakazakii ATCC BAA-894 (CS WT) and a fliF::Tn5 mutant was performed, including the ability of both strains to adhere to and invade N1E-115 cells. To achieve this goal, a nonmotile C. sakazakii ATCC BAA-894 fliF::Tn5 (CS fliF::Tn5) strain was generated using an EZ-Tn5 <KAN-2>Tnp Transposome kit. Analysis of differential protein expression showed that 81.49% (361/443) of the proteins were expressed in both strains, 8.35% (37/443) were exclusively expressed in the CS WT strain, and 10.16% (45/443) were exclusively expressed in the CS fliF::Tn5 strain. The main exclusively expressed proteins in the CS WT strain were classified into the "cell motility" and "signal transduction mechanisms" subcategories. The proteins exclusively expressed in the CS fliF::Tn5 strain were classified into the following subcategories: "intracellular trafficking, secretion, and vesicular transport", "replication, recombination, and repair", "nucleotide transport and metabolism", "carbohydrate transport and metabolism", "coenzyme transport and metabolism", and "lipid transport and metabolism". Expression of the Cpa protein was detected in both strains, but Cpa was more abundant in the CS WT strain than in the CS fliF::Tn5 strain. A significant increase (p = 0.0001) in adherence to N1E-115 cells was observed in the nonmotile CS fliF::Tn5 strain (31.3 × 106 CFU/mL) compared to the CS WT strain (14.5 × 106 CFU/mL). Additionally, the CS WT strain showed a 0.17% invasion frequency in N1E-115 cells, which was significantly higher (p = 0.01) than that of the nonmotile CS fliF::Tn5 strain. In conclusion, the proteins involved in the motility were mainly identified by proteomic analysis in the CS WT strain compared to the CS fliF::Tn5 strain. Our data indicate that flagella are required to promote the invasion of N1E-115 cells and that the absence of flagella significantly increases the adherence to N1E-115 cells.
Collapse
Affiliation(s)
- Esteban-Kenel Veronica
- Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez, Ciudad de México, Mexico; Laboratorio de Ingeniería Genética, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Ochoa Sara A
- Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez, Ciudad de México, Mexico
| | - Curiel-Quesada Everardo
- Laboratorio de Ingeniería Genética, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Quezada Héctor
- Unidad de Investigación Epidemiológica en Endocrinología y Nutrición. Hospital Infantil de México Federico Gómez, Ciudad de México, Mexico
| | - Medina-Contreras Oscar
- Unidad de Investigación Epidemiológica en Endocrinología y Nutrición. Hospital Infantil de México Federico Gómez, Ciudad de México, Mexico
| | - Fernández-Rendón Elizabeth
- Laboratorio de Microbiología Sanitaria, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Rosas-Pérez Irma
- Laboratorio de Aerobiología, Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Arellano-Galindo José
- Área de Virología, Laboratorio de Infectología, Hospital Infantil de México Federico Gómez, Ciudad de México, Mexico
| | - Cisneros Bulmaro
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Hernandez-Castro Rigoberto
- Departamento de Ecología de Agentes Patógenos. Hospital General "Dr. Manuel Gea González", Delegación Tlalpan, México D., 14080, Mexico
| | - Xicohtencatl-Cortes Juan
- Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez, Ciudad de México, Mexico.
| | - Cruz-Córdova Ariadnna
- Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez, Ciudad de México, Mexico.
| |
Collapse
|
22
|
An acid-tolerance response system protecting exponentially growing Escherichia coli. Nat Commun 2020; 11:1496. [PMID: 32198415 PMCID: PMC7083825 DOI: 10.1038/s41467-020-15350-5] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 03/05/2020] [Indexed: 01/05/2023] Open
Abstract
The ability to grow at moderate acidic conditions (pH 4.0–5.0) is important to Escherichia coli colonization of the host’s intestine. Several regulatory systems are known to control acid resistance in E. coli, enabling the bacteria to survive under acidic conditions without growth. Here, we characterize an acid-tolerance response (ATR) system and its regulatory circuit, required for E. coli exponential growth at pH 4.2. A two-component system CpxRA directly senses acidification through protonation of CpxA periplasmic histidine residues, and upregulates the fabA and fabB genes, leading to increased production of unsaturated fatty acids. Changes in lipid composition decrease membrane fluidity, F0F1-ATPase activity, and improve intracellular pH homeostasis. The ATR system is important for E. coli survival in the mouse intestine and for production of higher level of 3-hydroxypropionate during fermentation. Furthermore, this ATR system appears to be conserved in other Gram-negative bacteria. The ability to grow at acidic pH is crucial for E. coli colonization of the host’s intestine. Here, the authors identify an acid-tolerance response system that is important for E. coli exponential growth at pH 4.2, survival in the mouse intestine, and production of 3-hydroxypropionate during fermentation.
Collapse
|
23
|
Zhou A, Cao Y, Zhou D, Hu S, Tan W, Xiao X, Yu Y, Li X. Global transcriptomic analysis of Cronobacter sakazakii CICC 21544 by RNA-seq under inorganic acid and organic acid stresses. Food Res Int 2019; 130:108963. [PMID: 32156398 DOI: 10.1016/j.foodres.2019.108963] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 12/23/2019] [Accepted: 12/25/2019] [Indexed: 01/07/2023]
Abstract
Cronobacter sakazakii is a common foodborne pathogen that can tolerate various stress conditions. Acidic environment is a common stress condition encountered by bacteria in food processing and gastrointestinal digestion, including both inorganic and organic acids. In order to elucidate the Acid Tolerance Response (ATR) of C. sakazakii, we performed high-throughput RNA-seq to compare gene expression under hydrochloric acid and citric acid stresses. In this study, 107 differentially expressed genes (DEGs) were identified in both acids, of which 85 DEGs were functionally related to the regulation of acid tolerance. Multiple layers of mechanisms may be applied by C. sakazakii in response to acid stress: Firstly, in order to reduce excessive intracellular protons, C. sakazakii pumps them out through trans-membrane proteins or consumes them through metabolic reactions. Secondly, under acidic conditions, a large amount of reactive oxygen species and hydroxyl radicals accumulate in the cells, resulting in oxidative damage. C. sakazakii protects cells by up-regulating the antioxidant stress genes such as soxS and madB. Thirdly, C. sakazakii chooses energy efficient metabolic pathways to reduce energy consumption and maintain necessary processes. Finally, genes involved in chemotaxis and motility were differentially expressed to respond to different acidic conditions. This study systematically analyzed the acid-resistant mechanism of C. sakazakii under the stress of organic and inorganic acids, and provided a theoretical basis for better control of its contamination in food.
Collapse
Affiliation(s)
- Ailian Zhou
- School of Food Sciences and Engineering, South China University of Technology, Guangzhou City, Guangdong Province 510640, China
| | - Yifang Cao
- School of Food Sciences and Engineering, South China University of Technology, Guangzhou City, Guangdong Province 510640, China
| | - Donggen Zhou
- Ningbo International Travel Healthcare Center. No. 336 Liuting Street, Haishu District, Ningbo City, Zhejiang Province 315012, China
| | - Shuangfang Hu
- Key Laboratory of Molecular Epidemiology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen City, Guangdong Province 518055, China
| | - Wanjing Tan
- School of Food Sciences and Engineering, South China University of Technology, Guangzhou City, Guangdong Province 510640, China
| | - Xinglong Xiao
- School of Food Sciences and Engineering, South China University of Technology, Guangzhou City, Guangdong Province 510640, China.
| | - Yigang Yu
- School of Food Sciences and Engineering, South China University of Technology, Guangzhou City, Guangdong Province 510640, China
| | - Xiaofeng Li
- State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Sciences, South China University of Technology, 381 Wusan Road, Tianhe District, Guangzhou City 510640, Guangdong Province, China.
| |
Collapse
|
24
|
Bai Y, Yu H, Guo D, Fei S, Shi C. Survival and Environmental Stress Resistance of Cronobacter sakazakii Exposed to Vacuum or Air Packaging and Stored at Different Temperatures. Front Microbiol 2019; 10:303. [PMID: 30842765 PMCID: PMC6391331 DOI: 10.3389/fmicb.2019.00303] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 02/05/2019] [Indexed: 11/13/2022] Open
Abstract
The aim of this study was to evaluate the survival of Cronobacter sakazakii exposed to vacuum or air packaging, then stored at 4, 10, or 25°C, and the environmental stress resistance of vacuum-packaged or air-packaged bacterial cells were determined by subjecting the cells to reconstituted infant formula at 50°C, in acid (simulated gastric fluid, pH = 3.5), and in bile salt [bile salt solution, 5% (wt/vol)]. A cocktail culture of C. sakazakii desiccated on the bottom of sterile petri plates was air-packaged or vacuum-packaged and then stored at 4, 10, or 25°C for 10 days. The viable cell populations during storage were examined, and the vacuum-packaged and air-packaged cells (stored at 10°C for 4 days) were subsequently exposed to heat, acid, or bile salt. The results show that the populations of vacuum-packaged and air-packaged C. sakazakii were reduced by 1.6 and 0.9 log colony-forming units (CFU)/ml at 4°C and by 1.6 and 1.3 log CFU/ml at 25°C, respectively, in 10 days. At 10°C, significant reductions of 3.1 and 2.4 log CFU/ml were observed for vacuum-packaged and air-packaged cells, respectively. Vacuum packaging followed by storage at 10°C for 4 days caused significant decreases in the resistance of C. sakazakii to heat, acid, and bile salt conditions compared with air packaging. These results suggest that the application of vacuum packaging for powdered infant formula could be useful to minimize the risk of C. sakazakii.
Collapse
Affiliation(s)
| | | | | | | | - Chao Shi
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| |
Collapse
|
25
|
Tong L, Zhang M, Zhang X, Wang Y, Ou D, Zhang J, Wu Q, Ye Y. Exploration of factors in response to low acid tolerance using random mutagenesis in Cronobacter malonaticus. Food Res Int 2018; 116:994-999. [PMID: 30717032 DOI: 10.1016/j.foodres.2018.09.037] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 08/26/2018] [Accepted: 09/13/2018] [Indexed: 11/25/2022]
Abstract
Cronobacter species are associated with rare but severe infections in newborns, and their tolerance to environmental stress such as acid stress has been described. However, the factors involved in low acid tolerance in Cronobacter are poorly understood. Here, a transposon mutagenesis approach was used to explore the factors involved in acid tolerance in C. malonaticus. Eight mutants from mutant library (n = 215) were successfully screened through a comparison of growth with wild type (WT) strain under acid stress (pH 4.0). Eight mutating sites including glucosyltransferase MdoH, extracellular serine protease, sulfate transporter, phosphate transporter permease subunit PstC, lysine transporter, nitrogen regulation protein NR (II), D-alanine-D-alanine ligase, glucan biosynthesis protein G were successfully identified by arbitrary polymerase chain reaction and sequencing. The biomass of biofilm of eight mutants were significantly reduced using crystal violet staining (CVS) compared with that of WT. furthermore, the more compact biofilms of WT was observed than those of eight mutants through scanning electron microscopy (SEM), and confocal laser scanning microscopy (CLSM). Disassembly of biofilms appeared among mutants and WT strain from 48 h to 72 h through the increasing of dead cells and reduction of viable cells and exopolysaccharide. The study reveals the molecular basis involved in acid tolerance of C. malonaticus and a possible relationship between biofilm formation and acid tolerance, which provides valuable information for survival of C. malonaticus under acid stress.
Collapse
Affiliation(s)
- Liaowang Tong
- School of Food Science and Engineering, Hefei University of Technology, Hefei 230009, China; State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbiology Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China
| | - Maofeng Zhang
- School of Food Science and Engineering, Hefei University of Technology, Hefei 230009, China; State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbiology Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China
| | - Xiyan Zhang
- School of Food Science and Engineering, Hefei University of Technology, Hefei 230009, China
| | - Yaping Wang
- School of Food Science and Engineering, Hefei University of Technology, Hefei 230009, China
| | - Dexin Ou
- School of Food Science and Engineering, Hefei University of Technology, Hefei 230009, China
| | - Jumei Zhang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbiology Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China
| | - Qingping Wu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbiology Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China.
| | - Yingwang Ye
- School of Food Science and Engineering, Hefei University of Technology, Hefei 230009, China; State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbiology Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China.
| |
Collapse
|
26
|
Chen S, Zhou Q, Tan X, Li Y, Ren G, Wang X. The Global Response of Cronobacter sakazakii Cells to Amino Acid Deficiency. Front Microbiol 2018; 9:1875. [PMID: 30154778 PMCID: PMC6102319 DOI: 10.3389/fmicb.2018.01875] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Accepted: 07/25/2018] [Indexed: 12/29/2022] Open
Abstract
Cronobacter species can cause necrotizing enterocolitis and meningitis in neonates and infants, their infection is closely relevant to their responses to extreme growth conditions. In this study, the response of Cronobacter species to amino acid deficiency has been investigated. Four Cronobacter species formed smooth colonies when grown on the solid LB medium, but formed mucoid colonies when grown on the amino acid deficient M9 medium. When the mucoid colonies were stained with tannin mordant, exopolysaccharide around the cells could be discerned. The exopolysaccharide was isolated, analyzed, and identified as colanic acid. When genes wcaD and wcaE relevant to colanic acid biosynthesis were deleted in Cronobacter sakazakii BAA-894, no exopolysaccharide could be produced, confirming the exopolysaccharide formed in C. sakazakii grown in M9 is colanic acid. On the other hand, when genes rcsA, rcsB, rcsC, rcsD, or rcsF relevant to Rcs phosphorelay system was deleted in C. sakazakii BAA-894, colanic acid could not be produced, suggesting that the production of colanic acid in C. sakazakii is regulated by Rcs phosphorelay system. Furthermore, C. sakazakii BAA-894 grown in M9 supplemented with amino acids could not produce exopolysaccharide. Transcriptomes of C. sakazakii BAA-894 grown in M9 or LB were analyzed. A total of 3956 genes were differentially expressed in M9, of which 2339 were up-regulated and 1617 were down-regulated. When C. sakazakii BAA-894 was grown in M9, the genes relevant to the biosynthesis of exopolysaccharide were significantly up-regulated; on the other hand, the genes relevant to the flagellum formation and chemotaxis were significantly down-regulated; in addition, most genes relevant to various amino acid biosynthesis were also significantly regulated. The results demonstrate that amino acid deficiency has a global impact on C. sakazakii cells.
Collapse
Affiliation(s)
- Si Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Qing Zhou
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Xin Tan
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| | - Ye Li
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Ge Ren
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Xiaoyuan Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| |
Collapse
|
27
|
|
28
|
Lang E, Guyot S, Alvarez-Martin P, Perrier-Cornet JM, Gervais P. Caco-2 Invasion by Cronobacter sakazakii and Salmonella enterica Exposed to Drying and Heat Treatments in Dried State in Milk Powder. Front Microbiol 2017; 8:1893. [PMID: 29033925 PMCID: PMC5627024 DOI: 10.3389/fmicb.2017.01893] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 09/15/2017] [Indexed: 12/22/2022] Open
Abstract
Due to the ability of foodborne pathogens to survive in low moisture food, the decontamination of milk powder is an important issue in food protection. The safety of food products is, however, not always insured and the different steps in the processing of food involve physiological and metabolic changes in bacteria. Among these changes, virulence properties may also be affected. In this study, the effect of drying and successive thermal treatments on the invasion capacity of Salmonella Typhimurium, Salmonella Senftenberg, and Cronobacter sakazakii was assessed. Bacteria were dried on milk powder at three different water activity levels (0.25, 0.58, and 0.80) and heated at two different temperatures (90°C and 100°C) for 30 and 120 s. After recovery, stressed bacterial populations were placed in contact with Caco-2 cells to estimate their invasion capacity. Our results show that drying increases the invasion capacity of foodborne pathogens, but that heat treatment in the dried state did not exert a selective pressure on bacterial cells depending on their invasion capacity after drying. Taken together, our findings add to the sum of knowledge on food safety in dried food products and provide insight into the effects of food processing.
Collapse
Affiliation(s)
- Emilie Lang
- UMR PAM A 02.102 Procédés Alimentaires et Microbiologiques, Université de Bourgogne Franche-Comté/AgroSup Dijon, Dijon, France.,Novolyze, Dijon, France
| | - Stéphane Guyot
- UMR PAM A 02.102 Procédés Alimentaires et Microbiologiques, Université de Bourgogne Franche-Comté/AgroSup Dijon, Dijon, France
| | | | - Jean-Marie Perrier-Cornet
- UMR PAM A 02.102 Procédés Alimentaires et Microbiologiques, Université de Bourgogne Franche-Comté/AgroSup Dijon, Dijon, France
| | - Patrick Gervais
- UMR PAM A 02.102 Procédés Alimentaires et Microbiologiques, Université de Bourgogne Franche-Comté/AgroSup Dijon, Dijon, France
| |
Collapse
|
29
|
Virulent and pathogenic features on the Cronobacter sakazakii polymyxin resistant pmr mutant strain s-3. Microb Pathog 2017; 110:359-364. [DOI: 10.1016/j.micpath.2017.07.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 07/11/2017] [Accepted: 07/11/2017] [Indexed: 11/18/2022]
|
30
|
Comparative proteomic analysis of Cronobacter sakazakii by iTRAQ provides insights into response to desiccation. Food Res Int 2017; 100:631-639. [PMID: 28873731 DOI: 10.1016/j.foodres.2017.06.051] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 06/18/2017] [Accepted: 06/20/2017] [Indexed: 11/21/2022]
Abstract
Cronobacter sakazakii is a foodborne pathogen throughout the world and survives extremely desiccation stress. However, the molecular basis involved in desiccation resistance of C. sakazakii is still unknown. In this study, the potential desiccation resistance factors of C. sakazakii ATCC 29544 were determined using iTRAQ-based quantitative proteomic analysis. A total of 2775 proteins were identified by iTRAQ, of which 233 showed a different protein expression between control group and desiccation stress group. Among these 233 proteins identified as desiccation resistance proteins, there were 146 proteins downregulated and 87 proteins upregulated. According to the comprehensive proteome coverage analysis, C. sakazakii increased its resistance to desiccation by reducing the gene involved with unnecessary survival functions such as those used for virulence, adhesion, invasion and flagella assembly, while increasing gene expression of genes used in withstanding osmotic stress such as those genes involved in trehalose and betaine uptake. However, the mechanism involved in amino acid metabolism in an osmotic stress response, including the producing of γ-aminobutyric acid in C. sakazakii is still uncertain. This is the first report to determine the potential desiccation resistant factors of C. sakazakii at the proteomic levels.
Collapse
|
31
|
Hu S, Yu Y, Wu X, Xia X, Xiao X, Wu H. Simultaneous detection and identification of pathogenic Cronobacter
species by high-resolution melting analysis in powdered infant formulas. INT J DAIRY TECHNOL 2017. [DOI: 10.1111/1471-0307.12410] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shuangfang Hu
- School of Food Science and Engineering; South China University of Technology; Guangzhou Guangdong 510640 China
| | - Yigang Yu
- School of Food Science and Engineering; South China University of Technology; Guangzhou Guangdong 510640 China
| | - Xinwei Wu
- Department of Microbiology; Guangzhou Center for Disease Control and Prevention; Qide Road No. 2 Guangzhou Guangdong 510440 China
| | - Xingzhou Xia
- College of Food Science and Technology; Guangdong Ocean University; Zhanjiang Guangdong 524088 China
| | - Xinglong Xiao
- School of Food Science and Engineering; South China University of Technology; Guangzhou Guangdong 510640 China
| | - Hui Wu
- School of Food Science and Engineering; South China University of Technology; Guangzhou Guangdong 510640 China
| |
Collapse
|
32
|
Fei P, Jiang Y, Feng J, Forsythe SJ, Li R, Zhou Y, Man C. Antibiotic and Desiccation Resistance of Cronobacter sakazakii and C. malonaticus Isolates from Powdered Infant Formula and Processing Environments. Front Microbiol 2017; 8:316. [PMID: 28303125 PMCID: PMC5332417 DOI: 10.3389/fmicb.2017.00316] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 02/15/2017] [Indexed: 11/20/2022] Open
Abstract
This study evaluated the antimicrobial and desiccation resistance of Cronobacter sakazakii and Cronobacter malonaticus isolates from powdered infant formula and processing environments. The antimicrobial susceptibility tests showed that the 70 Cronobacter strains, representing 19 sequence types, were susceptible to the most of the antibiotics except for amoxicillin-clavulanate, ampicillin, and cefazolin. Furthermore, the growth of six C. sakazakii and two C. malonaticus strains from different sequence types (STs) in hyperosmotic media was measured. The growth of the two C. sakazakii strains (CE1 and CE13) from the neonatal pathovars ST4 and ST8, were significantly higher (p < 0.05) than that of other strains. C. malonaticus strain CM35 (ST201) was the slowest grower in all strains, and most could not grow in more than 8% NaCl solution. Also the survival of these strains under desiccation conditions was followed for 1 year. The viable count of Cronobacter spp. under desiccation conditions was reduced on average by 3.02 log cycles during 1 year, with CE13 (ST8) being the most desiccation resistant strain. These results will improve our understanding of the persistence of the two closely related species C. sakazakii and C. malonaticus which are of concern for neonatal and adult health.
Collapse
Affiliation(s)
- Peng Fei
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural UniversityHarbin, China
| | - Yujun Jiang
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural UniversityHarbin, China
- National Research Center of Dairy Engineering and Technology, Northeast Agricultural UniversityHarbin, China
| | - Jing Feng
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural UniversityHarbin, China
| | - Stephen J. Forsythe
- Pathogen Research Group, School of Science and Technology, Nottingham Trent UniversityNottingham, UK
| | - Ran Li
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural UniversityHarbin, China
| | - Yanhong Zhou
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural UniversityHarbin, China
| | - Chaoxin Man
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural UniversityHarbin, China
| |
Collapse
|
33
|
Du XJ, Zhang X, Li P, Xue R, Wang S. Screening of genes involved in interactions with intestinal epithelial cells in Cronobacter sakazakii. AMB Express 2016; 6:74. [PMID: 27637944 PMCID: PMC5023641 DOI: 10.1186/s13568-016-0246-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Accepted: 09/07/2016] [Indexed: 11/10/2022] Open
Abstract
Cronobacter sakazakii possesses a significant ability to adhere to and invade epithelial cells in its host. However, the molecular mechanisms underlying this process are poorly understood. In the current study, the adhesive and invasive capabilities of 56 C. sakazakii strains against human epithelial cells were evaluated, and one of them was selected for construction of a mutant library using the Tn5 transposon. In a systematic analysis of the adhesive and invasive capabilities of 1084 mutants, 10 mutants that showed more than a 50 % reduction in adhesion or invasion were obtained. Tail-PCR was used to sequence the flanking regions of the inserted transposon and 8 different genes (in 10 different mutants) were identified that encoded an exonuclease subunit, a sugar transporter, a transcriptional regulator, two flagellar biosynthesis proteins, and three hypothetical proteins. Raman spectroscopy was used to analyze variations in the biochemical components of the mutants, and the results showed that there were fewer amide III proteins, protein -CH deformations, nucleic acids and tyrosines and more phenylalanine, carotenes, and fatty acids in the mutants than in the wild type strain. Real-time PCR was used to further confirm the involvement of the genes in the adhesive and invasive abilities of C. sakazakii, and the results indicated that the expression levels of the 8 identified genes were upregulated 1.2- to 11.2-fold. The results of this study provide us with insight into the mechanism by which C. sakazakii infects host cells at molecular level.
Collapse
|
34
|
Li R, Fei P, Man C, Lou B, Niu J, Feng J, Sun L, Li M, Jiang Y. Tea polyphenols inactivate Cronobacter sakazakii isolated from powdered infant formula. J Dairy Sci 2016; 99:1019-1028. [DOI: 10.3168/jds.2015-10039] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 10/03/2015] [Indexed: 11/19/2022]
|
35
|
The response of foodborne pathogens to osmotic and desiccation stresses in the food chain. Int J Food Microbiol 2016; 221:37-53. [PMID: 26803272 DOI: 10.1016/j.ijfoodmicro.2015.12.014] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 12/22/2015] [Accepted: 12/30/2015] [Indexed: 12/24/2022]
Abstract
In combination with other strategies, hyperosmolarity and desiccation are frequently used by the food processing industry as a means to prevent bacterial proliferation, and particularly that of foodborne pathogens, in food products. However, it is increasingly observed that bacteria, including human pathogens, encode mechanisms to survive and withstand these stresses. This review provides an overview of the mechanisms employed by Salmonella spp., Shiga toxin producing E. coli, Cronobacter spp., Listeria monocytogenes and Campylobacter spp. to tolerate osmotic and desiccation stresses and identifies gaps in knowledge which need to be addressed to ensure the safety of low water activity and desiccated food products.
Collapse
|
36
|
Inhibitory effects of d-tryptophan on biofilm development by the foodborne Cronobacter sakazakii. Int Dairy J 2015. [DOI: 10.1016/j.idairyj.2015.05.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
|
37
|
Huertas JP, Álvarez-Ordóñez A, Morrissey R, Ros-Chumillas M, Esteban MD, Maté J, Palop A, Hill C. Heat resistance of Cronobacter sakazakii DPC 6529 and its behavior in reconstituted powdered infant formula. Food Res Int 2015. [DOI: 10.1016/j.foodres.2015.01.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|