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Kirthika P, Senevirathne A, Park S, Aganja RP, Kim IS, Tae HJ, Lee JH. Intracellular Survival and Pathogenicity Modulation of Salmonella Lon, CpxR, and RfaL Mutants Used as Live Bacterial Vectors under Abiotic Stress, Unveiling the Link between Stress Response and Virulence in Epithelial Cells. Int J Mol Sci 2024; 25:9056. [PMID: 39201742 PMCID: PMC11354574 DOI: 10.3390/ijms25169056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2024] [Revised: 08/19/2024] [Accepted: 08/19/2024] [Indexed: 09/03/2024] Open
Abstract
In the current study, two Salmonella Typhimurium strains, JOL 912 and JOL 1800, were engineered from the wild-type JOL 401 strain through in-frame deletions of the lon and cpxR genes, with JOL 1800 also lacking rfaL. These deletions significantly attenuated the strains, impairing their intracellular survival and creating unique immunological profiles. This study investigates the response of these strains to various abiotic stress conditions commonly experienced in vivo, including temperature, acidity, osmotic, and oxidative stress. Notably, cold stress induced a non-significant trend towards increased invasion by Salmonella compared to other stressors. Despite the observed attenuation, no significant alterations in entry mechanisms (trigger vs. zipper) were noted between these strains, although variations were evident depending on the host cell type. Both strains effectively localized within the cytoplasm, demonstrating their ability to invade and interact with the intracellular environment. Immunologically, JOL 912 elicited a robust response, marked by substantial activation of nuclear factor kappa B (NF-kB), and chemokines, interleukin 8 (CXCL 8) and interleukin 10 (CXCL 10), comparable to the wild-type JOL 401 (over a fourfold increase compared to JOL 1800). In contrast, JOL 1800 exhibited a minimal immune response. Additionally, these attenuations influenced the expression of cyclins D1 and B1 and caspases 3 and 7, indicating cell cycle arrest at the G2/M phase and promotion of the G0/G1 to S phase transition, alongside apoptosis in infected cells. These findings provide valuable insights into the mechanisms governing the association, internalization, and survival of Salmonella mutants, enhancing our understanding of their regulatory effects on host cell physiology.
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Affiliation(s)
- Perumalraja Kirthika
- College of Veterinary Medicine, Jeonbuk National University, Iksan 54596, Republic of Korea; (P.K.); (A.S.); (R.P.A.)
| | - Amal Senevirathne
- College of Veterinary Medicine, Jeonbuk National University, Iksan 54596, Republic of Korea; (P.K.); (A.S.); (R.P.A.)
| | - Sungwoo Park
- College of Veterinary Medicine, Jeonbuk National University, Iksan 54596, Republic of Korea; (P.K.); (A.S.); (R.P.A.)
| | - Ram Prasad Aganja
- College of Veterinary Medicine, Jeonbuk National University, Iksan 54596, Republic of Korea; (P.K.); (A.S.); (R.P.A.)
| | - In-Shik Kim
- College of Veterinary Medicine and Institute of Animal Transplantation, Jeonbuk National University, Iksan 54596, Republic of Korea; (I.-S.K.); (H.-J.T.)
| | - Hyun-Jin Tae
- College of Veterinary Medicine and Institute of Animal Transplantation, Jeonbuk National University, Iksan 54596, Republic of Korea; (I.-S.K.); (H.-J.T.)
| | - John Hwa Lee
- College of Veterinary Medicine, Jeonbuk National University, Iksan 54596, Republic of Korea; (P.K.); (A.S.); (R.P.A.)
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Gonçalves MPMBB, do Prado-Silva L, Sant'Ana AS. Emergent methods for inactivation of Cronobacter sakazakii in foods: A systematic review and meta-analysis. Int J Food Microbiol 2024; 421:110777. [PMID: 38909488 DOI: 10.1016/j.ijfoodmicro.2024.110777] [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: 02/08/2024] [Revised: 05/24/2024] [Accepted: 05/31/2024] [Indexed: 06/25/2024]
Abstract
Cronobacter sakazakii is a potentially pathogenic bacterium that is resistant to osmotic stress and low aw, and capable of persisting in a desiccated state in powdered infant milks. It is widespread in the environment and present in various products. Despite the low incidence of cases, its high mortality rates of 40 to 80 % amongst neonates make it a microorganism of public health interest. This current study performed a comparative assessment between current reduction methods applied for C. sakazakii in various food matrices, indicating tendencies and relevant parameters for process optimization. A systematic review and meta-analysis were conducted, qualitatively identifying the main methods of inactivation and control, and quantitatively evaluating the effect of treatment factors on the reduction response. Hierarchical clustering dendrograms led to conclusions on the efficiency of each treatment. Review of recent research trend identified a focus on the potential use of alternative treatments, with most studies related to non-thermal methods and dairy products. Using random-effects meta-analysis, a summary effect-size of 4-log was estimated; however, thermal methods and treatments on dairy matrices displayed wider dispersions - of τ2 = 8.1, compared with τ2 = 4.5 for vegetal matrices and τ2 = 4.0 for biofilms. Meta-analytical models indicated that factors such as chemical concentration, energy applied, and treatment time had a more significant impact on reduction than the increase in temperature. Non-thermal treatments, synergically associated with heat, and treatments on dairy matrices were found to be the most efficient.
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Affiliation(s)
| | - Leonardo do Prado-Silva
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Brazil
| | - Anderson S Sant'Ana
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Brazil.
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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.
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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.
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Wang Y, Ling N, Wang Y, Ou D, Liang Z, Li G, Zhao H, Ye Y. Effect of ferric ions on Cronobacter sakazakii growth, biofilm formation, and swarming motility. Int J Food Microbiol 2024; 408:110418. [PMID: 37857020 DOI: 10.1016/j.ijfoodmicro.2023.110418] [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: 05/17/2023] [Revised: 09/22/2023] [Accepted: 09/23/2023] [Indexed: 10/21/2023]
Abstract
Cronobacter sakazakii (C. sakazakii) is a common food-borne pathogen that induces meningitis, sepsis, and necrotizing enterocolitis, primarily in newborns and infants. Iron plays a pivotal role in the growth of cells and biofilm formation. However, the effects of hemin (ferric ion donor) on C. sakazakii cells are scarcely known. Here, we explored the effect of ferric ions on the growth of planktonic C. sakazakii, biofilm formation, and swarming motility by crystal violet staining (CVS), scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), and swarming assay. Our study demonstrated that ferric ions facilitated the growth of planktonic C. sakazakii, while hemin at concentrations ranging from 50 to 800 μmol/L promoted biofilm formation and at concentrations between 50 and 200 μmol/L enhanced the swarming motility of C. sakazakii. Furthermore, high hemin concentrations (400-800 μmol/L) were found to reduce flagellar length, as confirmed by transmission electron microscopy (TEM). These findings indicated that ferric ions mediated the swarming motility of C. sakazakii by regulating flagellar assembly. Finally, transcriptomic analysis of C. sakazakii was performed at hemin concentrations of 0, 50, and 200 μmol/L, which revealed that several genes associated with iron transport and metabolism, and flagellar assembly were essential for the survival of C. sakazakii under hemin treatment. Our findings revealed the molecular basis of ferric ions on C. sakazakii growth and biofilm formation, thus providing a novel perspective for its prevention and control.
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Affiliation(s)
- Yang Wang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230601, China
| | - Na Ling
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230601, China
| | - Yaping Wang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230601, China
| | - Dexin Ou
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230601, China
| | - Zhao Liang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230601, China
| | - Guoqing Li
- Institute of Horticulture Research, Anhui Academy of Agricultural Sciences, Hefei 230031, China
| | - Hongyuan Zhao
- Institute of Horticulture Research, Anhui Academy of Agricultural Sciences, Hefei 230031, China.
| | - Yingwang Ye
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230601, China.
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Chauhan R, Tall BD, Gopinath G, Azmi W, Goel G. Environmental risk factors associated with the survival, persistence, and thermal tolerance of Cronobacter sakazakii during the manufacture of powdered infant formula. Crit Rev Food Sci Nutr 2023; 63:12224-12239. [PMID: 35838158 DOI: 10.1080/10408398.2022.2099809] [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 sakazakii is an opportunistic foodborne pathogen of concern for foods having low water activity such as powdered infant formula (PIF). Its survival under desiccated stress can be attributed to its ability to adapt effectively to many different environmental stresses. Due to the high risk to neonates and its sporadic outbreaks in PIF, C. sakazakii received great attention among the scientific community, food industry and health care providers. There are many extrinsic and intrinsic factors that affect C. sakazakii survival in low-moisture foods. Moreover, short- or long-term pre-exposure to sub-lethal physiological stresses which are commonly encountered in food processing environments are reported to affect the thermal resistance of C. sakazakii. Additionally, acclimation to these stresses may render C. sakazakii resistance to antibiotics and other antimicrobial agents. This article reviews the factors and the strategies responsible for the survival and persistence of C. sakazakii in PIF. Particularly, studies focused on the influence of various factors on thermal resistance, antibiotic or antimicrobial resistance, virulence potential and stress-associated gene expression are reviewed.
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Affiliation(s)
- Rajni Chauhan
- Department of Biotechnology, Himachal Pradesh University, Shimla, India
| | | | - Gopal Gopinath
- Center for Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, USA
| | - Wamik Azmi
- Department of Biotechnology, Himachal Pradesh University, Shimla, India
| | - Gunjan Goel
- Department of Microbiology, School of Interdisciplinary and Applied Sciences, Central University of Haryana, Mahindra, India
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Wang Y, Ling N, Jiao R, Zhang X, Ren Y, Li H, Zhao W, Wu Q, Ye Y. Transcriptomic analysis reveals novel desiccation tolerance mechanism of Cronobacter based on type VI secretion system inhibition. Food Res Int 2023; 172:113143. [PMID: 37689845 DOI: 10.1016/j.foodres.2023.113143] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 06/12/2023] [Accepted: 06/13/2023] [Indexed: 09/11/2023]
Abstract
Cronobacter malonaticus (C. malonaticus) is a food-borne pathogen inducing severe infections both in infants and adults, and it could survive in dry powdered infant formula (PIF) for a long time, implying its strong tolerance to desiccation. However, the thorough molecular mechanism of resistance to desiccation remains elusive. When C. malonaticus was exposed to desiccation conditions (7, 15, and 30 d), transcriptomic analysis provided a universal adaptation strategy to withstand desiccation with the increased compatible solutes accumulation, activated stress resistance-related regulators, suppressed protein export and bacterial secretion system, and reduced other unessential survival functions including adhesion, invasion, virulence, and flagellar motility. Importantly, type VI secretion system (T6SS) genes exhibited significantly downregulated expressions, as well as markedly increased survival and viability of their mutants after desiccation treatment, revealing the negative regulation of T6SS in desiccation tolerance. Meanwhile, the decreased expressions of T6SS structure genes in other six species further confirmed the vital role of T6SS in desiccation tolerance of Cronobacter spp. Thus, our studies present a novel hypothesis of desiccation resistance in Cronobacter based on type VI secretion system inhibition, causing the reduction of macromolecule secretion such as effectors and hyperosmolality development within the cytomembrane, which allow Cronobacter to survive in desiccation.
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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
| | - Hui Li
- 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
| | - Qingping Wu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou, China
| | - Yingwang Ye
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China.
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Fan Y, Li P, Zhu D, Zhao C, Jiao J, Ji X, Du X. Effects of ESA_00986 Gene on Adhesion/Invasion and Virulence of Cronobacter sakazakii and Its Molecular Mechanism. Foods 2023; 12:2572. [PMID: 37444309 DOI: 10.3390/foods12132572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/28/2023] [Accepted: 06/29/2023] [Indexed: 07/15/2023] Open
Abstract
Cronobacter sakazakii is an opportunistic Gram-negative pathogen that has been identified as a causative agent of severe foodborne infections with a higher risk of mortality in neonates, premature infants, the elderly, and immunocompromised populations. The specific pathogenesis mechanisms of C. sakazakii, such as adhesion and colonization, remain unclear. Previously, we conducted comparative proteomic studies on the two strains with the stronger and weaker infection ability, respectively, and found an interesting protein, ESA_00986, which was more highly expressed in the strain with the stronger ability. This unknown protein, predicted to be a type of invasitin related to invasion, may be a critical factor contributing to its virulence. This study aimed to elucidate the precise roles of the ESA_00986 gene in C. sakazakii by generating gene knockout mutants and complementary strains. The mutant and complementary strains were assessed for their biofilm formation, mobility, cell adhesion and invasion, and virulence in a rat model. Compared with the wild-type strain, the mutant strain exhibited a decrease in motility, whereas the complementary strain showed comparable motility to the wild-type. The biofilm-forming ability of the mutant was weakened, and the mutant also exhibited attenuated adhesion to/invasion of intestinal epithelial cells (HCT-8, HICE-6) and virulence in a rat model. This indicated that ESA_00986 plays a positive role in adhesion/invasion and virulence. This study proves that the ESA_00986 gene encodes a novel virulence factor and advances our understanding of the pathogenic mechanism of C. sakazakii.
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Affiliation(s)
- Yufei Fan
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Ping Li
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Dongdong Zhu
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Chumin Zhao
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Jingbo Jiao
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Xuemeng Ji
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University, Tianjin 300071, China
| | - Xinjun Du
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
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Li P, Zong W, Zhang Z, Lv W, Ji X, Zhu D, Du X, Wang S. Effects and molecular mechanism of flagellar gene flgK on the motility, adhesion/invasion, and desiccation resistance of Cronobacter sakazakii. Food Res Int 2023; 164:112418. [PMID: 36738023 DOI: 10.1016/j.foodres.2022.112418] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 12/21/2022] [Accepted: 12/26/2022] [Indexed: 12/29/2022]
Abstract
Cronobacter sakazakii (C. sakazakii), a food-borne pathogen, can infect neonates, elderly and immunocompromised populations with a high infection and mortality rate. However, the specific molecular mechanism of its motility, biofilm formation, cell adhesion, and desiccation resistance remains unclear, and flagellum hook associated protein (FlgK), a main component of the flagellar complex, may be an important determinant of its virulence and desiccation resistance. In this study, the flgK mutant strain (ΔflgK) was constructed using the homologous recombination method, and the cpflgK complementary strain was obtained by gene complementation, followed by analysis of the difference between the wild type (WT), mutant, and complementary strains in mobility, biofilm formation, cell adhesion, and desiccation resistance. Results indicated that flgK gene played a positive role in motility and invasion, with no significant effect on biofilm formation. Interestingly, flagellar assembly gene deletion showed increased resistance of C. sakazakii to dehydration. The mechanism underlying the negative correlation of flgK gene with dehydration resistance was further investigated by using the high-throughput sequencing technology to compare the gene expression between WT and ΔflgK strains after drying. The results revealed up-regulation in the expression of 54 genes, including genes involved in osmosis and formate dehydrogenase, while down-regulation in the expression of 50 genes, including genes involved in flagellum hook and nitrate reductase. qRT-PCR analysis of the RNA-seq data further indicated that the flgK gene played an important role in the environmental stress resistance of C. sakazakii by up-regulating the formate dehydrogenase, betaine synthesis, and arginine deiminase pathways, due to dynamic proton imbalance caused by lack of flagella. This study facilitates our understanding of the roles of flgK in motion-related functions and the molecular mechanism of desiccation resistance in C. sakazakii.
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Affiliation(s)
- Ping Li
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Wenyue Zong
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Zhengyang Zhang
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Wen Lv
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Xuemeng Ji
- Tianjin Key Laboratory of Food Science and Health, College of Medicine, Nankai University, Tianjin 300071, China
| | - Dongdong Zhu
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Xinjun Du
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China.
| | - Shuo Wang
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China; Tianjin Key Laboratory of Food Science and Health, College of Medicine, Nankai University, Tianjin 300071, China.
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Comparison of Origanum Essential Oil Chemical Compounds and Their Antibacterial Activity against Cronobacter sakazakii. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27196702. [PMID: 36235238 PMCID: PMC9571376 DOI: 10.3390/molecules27196702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/03/2022] [Accepted: 10/03/2022] [Indexed: 11/07/2022]
Abstract
Origanum vulgare L. (oregano) is an aromatic plant with wide applications in the food and pharmaceutical industries. Cronobacter sakazakii, which has a high detection rate in powdered infant formula, adversely impacts susceptible individuals. Oregano essential oil (OEO) is a natural antibacterial agent that can be used to fight bacterial contamination. Here, OEO chemical compounds from eight oregano varieties were analyzed by gas chromatography–mass spectrometry and their antibacterial properties were assessed. The eight OEOs were clustered into two groups and were more diverse in group 2 than in group 1. Six compounds, including p-cymene, 3-thujene, γ-terpinene, thymol, carvacrol, and caryophyllene, were shared by eight OEOs. Among the eight oregano varieties, OEOs from O. vulgare sc2 had the strongest antibacterial activity against C. sakazaki, with the inhibition zone of 18.22mm. OEOs from O. vulgare jx, O. ‘Nvying’, O. vulgare ‘Ehuang’, and O. vulgare ssp. virens were also potent. Moreover, the antibacterial activity of OEOs was positively correlated with the relative content of thymol. As the main OEO antibacterial compound, thymol affected the normal growth and metabolism of C. sakazakii cells by destroying the bacterial membrane and decreasing the intracellular ATP concentration. Thus, in light of the antibacterial activity detected in the OEOs from the eight oregano varieties, this study provides a theoretical foundation for oregano cultivar management and development.
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The Role of ptsH in Stress Adaptation and Virulence in Cronobacter sakazakii BAA-894. Foods 2022; 11:foods11172680. [PMID: 36076869 PMCID: PMC9455513 DOI: 10.3390/foods11172680] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/21/2022] [Accepted: 08/30/2022] [Indexed: 11/17/2022] Open
Abstract
Cronobacter sakazakii, an emerging foodborne pathogen that was isolated primarily from powdered infant formula, poses an important issue in food safety due to its high stress tolerance and pathogenicity. The Hpr (encoded by ptsH gene) has been shown to regulate carbon metabolism as well as stress response and virulence. However, the functional properties of ptsH in C. sakzakii have not been investigated. In this study, we clarified the role of ptsH in the C. sakzakii stress response and virulence, and explored its possible regulatory mechanism by RNA-seq. Compared with wild-type, the ΔptsH mutant showed a slower growth rate in the log phase but no difference in the stationary phase. Moreover, the resistance to heat stress (65 °C, 55 °C), simulated gastric fluid (pH = 2.5), biofilm formation and adhesion to HT-29 cells of ΔptsH mutant were significantly decreased, whereas the oxidative resistance (1, 5, 10 mM H2O2), osmotic resistance (10%, 15%, 20% NaCl), and superoxide dismutase activity were enhanced. Finally, RNA-seq analysis revealed the sulfur metabolism pathway is significantly upregulated in the ΔptsH mutant, but the bacterial secretion system pathway is dramatically downregulated. The qRT-PCR assay further demonstrated that the ΔptsH mutant has elevated levels of genes that are related to oxidative and osmotic stress (sodA, rpoS, cpxA/R, osmY). This study provides a great understanding of the role of ptsH in diverse stress responses and virulence in C. sakazakii, and it contributes to our understanding of the genetic determinant of stress resistance and pathogenicity of this important foodborne pathogen.
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Hu L, Zhang S, Xue Y, Zhang Y, Zhang W, Wang S. Quantitative Detection of Viable but Nonculturable Cronobacter sakazakii Using Photosensitive Nucleic Acid Dye PMA Combined with Isothermal Amplification LAMP in Raw Milk. Foods 2022; 11:foods11172653. [PMID: 36076838 PMCID: PMC9455467 DOI: 10.3390/foods11172653] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/27/2022] [Accepted: 08/28/2022] [Indexed: 11/24/2022] Open
Abstract
An accurate method that rapidly detects the number of viable but nonculturable (VBNC) Cronobacter sakazakii was developed by combining propidium bromide with quantitative LAMP (PMA-QLAMP). The gyrB gene was the target for primers design. The optimal PMA treatment conditions were determined to eliminate the DNA amplification of 108 CFU/mL of dead C. sakazakii without affecting any viable C. sakazakii DNA amplification. Compared with the DNA of 24 strains of common non-C. sakazakii strains found in raw milk and dairy products, the DNA of only six C. sakazakii strains from different sources was amplified using PMA-QLAMP. The ability of PMA-QLAMP to quantitatively detect non-dead C. sakazakii in a 10% powdered infant formula (PIF) solution was limited to 4.3 × 102 CFU/mL and above concentrations. Pasteurizing 106 CFU/mL viable C. sakazakii yielded the maximum ratio of the VBNC C. sakazakii. PMA-QLAMP-based detection indicated that, although approximately 13% of 60 samples were positive for viable C. sakazakii, the C. sakazakii titers in these positive samples were low, and none entered the VBNC state under pasteurization. PMA-QLAMP showed potential as a specific and reliable method for detecting VBNC-C. sakazakii in pasteurized raw milk, thereby providing an early warning system that indicates potential contamination of PIF.
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Affiliation(s)
- Lianxia Hu
- College of Chemical Engineering, Shijiazhuang University, Shijiazhuang 050035, China
| | - Shufei Zhang
- College of Food Science and Biology, Hebei University of Science and Technology, Shijiazhuang 050018, China
| | - Yuling Xue
- Junlebao Dairy Group Co., Ltd., Shijiazhuang 050221, China
| | - Yaoguang Zhang
- Junlebao Dairy Group Co., Ltd., Shijiazhuang 050221, China
| | - Wei Zhang
- College of Life Sciences, Agricultural University of Hebei, Baoding 071001, China
| | - Shijie Wang
- College of Food Science and Biology, Hebei University of Science and Technology, Shijiazhuang 050018, China
- Junlebao Dairy Group Co., Ltd., Shijiazhuang 050221, China
- Correspondence: ; Tel.: +86-311-67362689
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12
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Li H, Zhao Y, Zhang J, Li W, You Q, Zeng X, Xu H. Silver nanoparticles reduce the tolerance of Cronobacter sakazakii to environmental stress by inhibiting expression of related genes. J Dairy Sci 2022; 105:6469-6482. [PMID: 35840406 DOI: 10.3168/jds.2022-21833] [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: 01/17/2022] [Accepted: 04/25/2022] [Indexed: 11/19/2022]
Abstract
Cronobacter sakazakii is a food-borne pathogen that is resistant to a variety of environmental stress conditions. It can survive in harsh environments. We studied the effects of silver nanoparticles (AgNP) on the environmental tolerance and biofilm formation of C. sakazakii. First, we determined the minimum inhibitory concentration (MIC) of AgNP to C. sakazakii and determined the growth curve of C. sakazakii treated with different concentrations of AgNP by using the plate counting method. After determining the sub-inhibition concentrations (SIC) of AgNP on C. sakazakii, we studied the effects of AgNP on the resistance of C. sakazakii to heat, desiccation, osmotic pressure, and acid. The antibiofilm activity of AgNP was also studied. Finally, real-time quantitative PCR was used to analyze the transcription levels of 16 genes related to the environmental tolerance of C. sakazakii. The SIC of AgNP significantly reduced the survival rate of C. sakazakii under various environmental stress conditions. The results showed that AgNP at 0.625 and 1.25 μg/mL significantly inhibited the formation of C. sakazakii biofilms. The expression levels of most genes were significantly downregulated in C. sakazakii cells treated with 0.625 and 1.25 μg/mL AgNP. Therefore, AgNP may reduce the environmental tolerance of C. sakazakii by inhibiting the expression of genes related to stress tolerance. Moreover, AgNP inhibited the production of ATP in C. sakazakii cells and the formation of C. sakazakii biofilms. Our research provides a theoretical basis for the application of AgNP in food packaging, bactericidal coatings, and other fields.
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Affiliation(s)
- Hui Li
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, China
| | - Yi Zhao
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, China
| | - Jingjing Zhang
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, China
| | - Wen Li
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, China
| | - Qixiu You
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, China
| | - Xianxiang Zeng
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, China
| | - Hengyi Xu
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, China.
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13
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Wang L, Wu P, Su Y, Wei Y, Guo X, Yang L, Wang M, Liu B. Detection of Genus and Three Important Species of Cronobacter Using Novel Genus- and Species-Specific Genes Identified by Large-Scale Comparative Genomic Analysis. Front Microbiol 2022; 13:885543. [PMID: 35722305 PMCID: PMC9201440 DOI: 10.3389/fmicb.2022.885543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 05/12/2022] [Indexed: 11/13/2022] Open
Abstract
The genus Cronobacter includes seven species; however, the strains of Cronobacter sakazakii, Cronobacter malonaticus, and Cronobacter turicensis were highly correlated with clinical infections. Rapid and reliable identification of these three species of Cronobacter is important in monitoring and controlling diseases caused by these bacteria. Here, we identified four pairs of novel marker genes for the Cronobacter genus, C. sakazakii, C. malonaticus, and C. turicensis based on large-scale comparative genomic analysis from 799 Cronobacter and 136,146 non-Cronobacter genomes, including 10 Franconibacter and eight Siccibacter, which are close relatives of Cronobacter. Duplex and multiplex PCR methods were established based on these newly identified marker genes. The reliability of duplex and multiplex PCR methods was validated with 74 Cronobacter and 90 non-Cronobacter strains. Strains of C. sakazakii, C. malonaticus, and C. turicensis could be detected accurately at both the genus and species level. Moreover, the newly developed methods enable us to detect 2.5 × 103 CFU/ml in pure culture. These data indicate that the accurate and sensitive established methods for Cronobacter can serve as valuable tools for the identification of these strains recovered from food, environmental, and clinical samples.
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Affiliation(s)
- Lu Wang
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China.,Institute of Infection and Inflammation, China Three Gorges University, Yichang, China.,Medical College, China Three Gorges University, Yichang, China
| | - Pan Wu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
| | - Yingying Su
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
| | - Yi Wei
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
| | - Xi Guo
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China.,Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China
| | - Lan Yang
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Key Laboratory of Dairy Products Processing, Ministry of Agriculture, Inner Mongolia Agricultural University, Huhhot, China
| | - Min Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China.,Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China
| | - Bin Liu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China.,Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Nankai University, Tianjin, China
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14
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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.
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15
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Tao H, Liao Q, Xu YI, Wang HL. Efficacy of Slightly Acidic Electrolyzed Water for Inactivation of Cronobacter sakazakii and Biofilm Cells. J Food Prot 2022; 85:511-517. [PMID: 34882220 DOI: 10.4315/jfp-21-263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 12/03/2021] [Indexed: 11/11/2022]
Abstract
ABSTRACT The disinfection efficacy and mechanism of activity of slightly acidic electrolyzed water (SAEW) were investigated against Cronobacter sakazakii. Treatment with three concentrations of SAEW decreased C. sakazakii by 23 to 55% after 2 min. Propidium iodide uptake and scanning electron micrographs indicated that SAEW treatment damaged cell integrity and changed membrane permeability resulting in leakage of nucleic acids (109.7%), intercellular proteins (692.3%), and potassium ions (53.6%). The ability to form biofilms was also reduced. SAEW treatment reduced the activity of superoxide dismutase and catalase from 100.73 and 114.18 U/mg protein to 50.03 and 50.13 U/mg protein, respectively. Expression of C. sakazakii response regulator genes (katG, rpoS, phoP, glpK, dacC, and CSK29544_RS05515) was reduced, which blocked repair of osmotic stress-induced damage and inhibited biofilm formation. These findings provide insight into the effects of SAEW on bacterial genotype and phenotype. HIGHLIGHTS
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Affiliation(s)
- Han Tao
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China.,School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China
| | - Qiaoming Liao
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China.,School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China
| | - Y I Xu
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China
| | - Hui-Li Wang
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China.,School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China
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16
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Feng Y, Zhu J, Wang Q, Cao H, He F, Guan Y, Li D, Yan J, Yang J, Xia Y, Dong M, Hu F, Cao M, Wang J, Ding X, Feng Y, Zou H, Han Y, Sun S, Zhang J, Tang A, Jiang M, Deng Y, Gao J, Jia Y, Zhao W, Zhang F. White common bean extract remodels the gut microbiota and ameliorates type 2 diabetes and its complications: A randomized double-blinded placebo-controlled trial. Front Endocrinol (Lausanne) 2022; 13:999715. [PMID: 36303868 PMCID: PMC9594986 DOI: 10.3389/fendo.2022.999715] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 09/23/2022] [Indexed: 12/03/2022] Open
Abstract
OBJECTIVE Excessive carbohydrate intake is a high risk factor for increased morbidity of type 2 diabetes (T2D). A novel regimen for the dietary care of diabetes that consists of a highly active α-amylase inhibitor derived from white common bean extract (WCBE) and sufficient carbohydrates intake was applied to attenuate T2D and its complications. Furthermore, the role of gut microbiota in this remission was also investigated. METHODS We conducted a 4-month randomized double-blinded placebo-controlled trial. During the intense intervention period, ninety subjects were randomly assigned to the control group (Group C) and WCBE group (Group W). Subjects in Group C were supplemented with 1.5 g of maltodextrin as a placebo. Subjects in Group W took 1.5 g of WCBE half an hour before a meal. Fifty-five participants continued the maintenance intervention receiving the previous dietary intervention whereas less frequent follow-up. The variation in biochemical, vasculopathy and neuropathy indicators and the structure of the fecal microbiota during the intervention was analyzed. RESULT Glucose metabolism and diabetic complications showed superior remission in Group W with a 0.721 ± 0.742% decline of glycosylated hemoglobin after 4 months. The proportion of patients with diabetic peripheral neuropathy (Toronto Clinical Scoring System, TCSS ≥ 6) was significantly lower in Group W than in Group C. Both the left and right sural sensory nerve conduction velocity (SNCV-left sural and SNCV-right sural) slightly decreased in Group C and slightly increased in Group W. Additionally, the abundances of Bifidobacterium, Faecalibacterium and Anaerostipes were higher in Group W, and the abundances of Weissella, Klebsiella, Cronobacter and Enterobacteriaceae_unclassified were lower than those in Group C at month 2. At the end of month 4, Bifidobacterium remained more abundant in Group W. CONCLUSION To our knowledge, this is the first report of improvement to diabetes complications by using a dietary supplement in such a short-term period. The enrichment of SCFA-producing bacteria might be responsible for the attenuation of T2D and its complications. CLINICAL TRIAL REGISTRATION NUMBER http://www.chictr.org.cn/edit.aspx?pid=23309&htm=4, identifier ChiCTR-IOR-17013656.
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Affiliation(s)
- Yuwei Feng
- Department of Nutrition, Affiliated Hospital of Jiangnan University, Wuxi, China
- Clinical Evaluation Center for Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, China
- Wuxi School of Medicine Jiangnan University, Wuxi, China
| | - Jie Zhu
- Clinical Evaluation Center for Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, China
- Department of Infection Control, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Qinyue Wang
- Department of Nutrition, Affiliated Hospital of Jiangnan University, Wuxi, China
- Clinical Evaluation Center for Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Hong Cao
- Department of Nutrition, Affiliated Hospital of Jiangnan University, Wuxi, China
- Clinical Evaluation Center for Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, China
- Department of Endocrinology, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Fang He
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, China
- School of Public Health (Shenzhen), Sun Yat-sen University, Guangzhou, China
| | - Yin Guan
- Yinglongqiao Community Health Service Center, Health Commision of Liangxi District, Wuxi, China
| | - Dan Li
- Department of Nutrition, Affiliated Hospital of Jiangnan University, Wuxi, China
- Clinical Evaluation Center for Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Jiai Yan
- Department of Nutrition, Affiliated Hospital of Jiangnan University, Wuxi, China
- Clinical Evaluation Center for Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Ju Yang
- Department of Nutrition, Affiliated Hospital of Jiangnan University, Wuxi, China
- Clinical Evaluation Center for Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Yanping Xia
- Department of Nutrition, Affiliated Hospital of Jiangnan University, Wuxi, China
- Clinical Evaluation Center for Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Meihua Dong
- Department of Health Promotion, Wuxi Center for Disease Control and Prevention, Wuxi, China
| | - Feng Hu
- Department of Functional Examination, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Min Cao
- Special Ward, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Jian Wang
- Department of Urology, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Xiaoying Ding
- Department of Endocrinology and Metabolism, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yufei Feng
- Mashan Community Healthcare Center, Health Commision of Binhu District, Wuxi, China
| | - Hong Zou
- Guangrui and Tongjiang Community Healthcare Center, Health Commision of Liangxi District, Wuxi, China
| | - Ying Han
- Guangrui and Tongjiang Community Healthcare Center, Health Commision of Liangxi District, Wuxi, China
| | - Su Sun
- Beidajie Community Healthcare Center, Health Commision of Liangxi District, Wuxi, China
| | - Jin Zhang
- Beidajie Community Healthcare Center, Health Commision of Liangxi District, Wuxi, China
| | - Aijuan Tang
- Beidajie Community Healthcare Center, Health Commision of Liangxi District, Wuxi, China
| | - Minhong Jiang
- Yangming Community Healthcare Center, Health Commision of Liangxi District, Wuxi, Jiangsu, China
| | - Yu Deng
- Yangming Community Healthcare Center, Health Commision of Liangxi District, Wuxi, Jiangsu, China
| | - Jianfen Gao
- Shanbei Community Healthcare Center, Health Commision of Liangxi District, Wuxi, China
| | - Yanxin Jia
- Shanbei Community Healthcare Center, Health Commision of Liangxi District, Wuxi, China
| | - Wei Zhao
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Feng Zhang
- Department of Nutrition, Affiliated Hospital of Jiangnan University, Wuxi, China
- Clinical Evaluation Center for Functional Food, Affiliated Hospital of Jiangnan University, Wuxi, China
- Wuxi School of Medicine Jiangnan University, Wuxi, China
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17
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Why Does Cronobacter sakazakii Survive for a Long Time in Dry Environments? Contribution of the Glass Transition of Dried Bacterial Cells. Microbiol Spectr 2021; 9:e0138421. [PMID: 34908438 PMCID: PMC8672889 DOI: 10.1128/spectrum.01384-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To investigate the mechanism of adaptation of Cronobacter sakazakii to desiccation stress, the present study focused on the glass transition phenomenon of dried bacterial cells, using a thermomechanical technique. The mechanical glass transition temperature (Tg) of dried C. sakazakii cells per se, prepared by different drying methods (air drying and freeze-drying) and with different water activity (aw) levels (0.43, 0.57, 0.75, and 0.87), were determined. In addition, we investigated the survival of two strains of C. sakazakii (JCM 1233 and JCM 2127) prepared by different drying methods under different storage temperatures (4, 25, and 42°C) and aw conditions (0.43 and 0.87). While the Tg of the air-dried C. sakazakii cells increased as the aw decreased, the freeze-dried C. sakazakii cells showed an unclear aw dependency of the Tg. Air-dried C. sakazakii cells showed a higher Tg than freeze-dried C. sakazakii cells at an aw of <0.57. Freeze-dried C. sakazakii cells were more rapidly inactivated than air-dried cells regardless of the difference in aw and temperature. The difference between the Tg and storage temperature was used as an index that took into consideration the differences in the drying methods and aw levels. As the difference between the Tg and storage temperature increased to >20°C, the dried C. sakazakii cells survived stably regardless of the drying method. In contrast, when the difference between the Tg and storage temperature was reduced to <10°C, the viable cell numbers in dried C. sakazakii cells were quickly decreased. Thus, the Tg is a key factor affecting the desiccation tolerance of C. sakazakii. IMPORTANCE The mechanical glass transition temperature (Tg) of dried Cronobacter sakazakii cells varied depending on differences in drying methods and water activity (aw) levels. Because the Tg of the dried bacterial cells varied depending on the drying method and aw, the Tg will play an important role as an operational factor in the optimization of dry food processing for controlling microbial contamination in the future. Furthermore, the differences between the Tg and storage temperature were introduced as an integrated index for survival of bacterial cells under a desiccation environment that took into consideration the differences in the drying methods and aw levels. As the difference between the Tg and storage temperature decreased to <10°C, the dried C. sakazakii cells were inactivated quickly, regardless of the drying methods. The relationship between Tg and storage temperature will contribute to understanding the desiccation tolerance of bacterial cells.
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18
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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.
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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
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19
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Bourdichon F, Betts R, Dufour C, Fanning S, Farber J, McClure P, Stavropoulou DA, Wemmenhove E, Zwietering MH, Winkler A. Processing environment monitoring in low moisture food production facilities: Are we looking for the right microorganisms? Int J Food Microbiol 2021; 356:109351. [PMID: 34500287 DOI: 10.1016/j.ijfoodmicro.2021.109351] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 07/16/2021] [Accepted: 07/28/2021] [Indexed: 11/27/2022]
Abstract
Processing environment monitoring is gaining increasing importance in the context of food safety management plans/HACCP programs, since past outbreaks have shown the relevance of the environment as contamination pathway, therefore requiring to ensure the safety of products. However, there are still many open questions and a lack of clarity on how to set up a meaningful program, which would provide early warnings of potential product contamination. Therefore, the current paper aims to summarize and evaluate existing scientific information on outbreaks, relevant pathogens in low moisture foods, and knowledge on indicators, including their contribution to a "clean" environment capable of limiting the spread of pathogens in dry production environments. This paper also outlines the essential elements of a processing environment monitoring program thereby supporting the design and implementation of better programs focusing on the relevant microorganisms. This guidance document is intended to help industry and regulators focus and set up targeted processing environment monitoring programs depending on their purpose, and therefore provide the essential elements needed to improve food safety.
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Affiliation(s)
- François Bourdichon
- Food Safety, Microbiology, Hygiene, 16 Rue Gaston de Caillavet, 75015 Paris, France; Facoltà di Scienze Agrarie, Alimentarie Ambientali, Università Cattolica del Sacro Cuore, Piacenza-Cremona, Italy.
| | - Roy Betts
- Campden BRI, Chipping Campden, Gloucestershire, United Kingdom
| | - Christophe Dufour
- Mérieux NutriSciences, 25 Boulevard de la Paix, 95891 Cergy Pontoise, France
| | - Séamus Fanning
- UCD - Centre for Food Safety, University College Dublin, Belfield, Dublin D04 N2E5, Ireland
| | - Jeffrey Farber
- Department of Food Science, University of Guelph, Guelph, Ontario, Canada
| | - Peter McClure
- Mondelēz International, Bournville Lane, Birmingham B30 2LU, United Kingdom
| | | | | | - Marcel H Zwietering
- Food Microbiology, Wageningen University, PO Box 17, 6700AA, Wageningen, The Netherlands
| | - Anett Winkler
- Cargill Germany GmbH, Cerestar str. 2, D-47809 Krefeld, Germany
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20
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Wu H, Wang Y, Yao Q, Fan L, Meng L, Zheng N, Li H, Wang J. Alkaline phosphatase attenuates LPS-induced liver injury by regulating the miR-146a-related inflammatory pathway. Int Immunopharmacol 2021; 101:108149. [PMID: 34634739 DOI: 10.1016/j.intimp.2021.108149] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/09/2021] [Accepted: 09/07/2021] [Indexed: 11/27/2022]
Abstract
Lipopolysaccharide (LPS) can remain in dairy products after the sterilization of milk powder and may pose a threat to the health of infants and young children. There is a large amount of alkaline phosphatase (ALP) in raw milk, which can remove the phosphate bond of LPS, thus, detoxifying it. ALP is regarded as an indicator of the success of milk sterilization due to its strong heat resistance. ALP can alleviate the toxicity of LPS in enteritis and nephritis models, but the mechanism by which oral-intake of ALP protects liver tissue from LPS stimulation is unclear. In this study, an in vivo acute mouse liver injury model was induced by C. sakazakii LPS (200 μg/kg) and used to verify the protective mechanism of ALP (200 U/kg) on mice livers. The related pathways were also verified by in vitro cell culture. Enzyme linked immunosorbent assays (ELISAs), quantitative reverse transcription PCR (RT-qPCR) and western blotting were used to detect the levels of inflammatory factors at the protein level and RNA level, and to confirm the inflammation of liver tissue caused by LPS. ALP was found to alleviate acute liver injury in vitro by activating miR-146a. We found that ALP could up-regulate the level of miR146a and subsequently alleviates the expression of TLR4, TNF-α, matured IL-1β, and NF-κB in mouse liver tissue and hepatocytes; thus, reducing liver inflammation. Herein, we demonstrated for the first time that oral-intake of ALP protected liver tissue by up-regulating the expression of miR-146a and alleviating inflammatory reactions; thus, providing a research basis for the proper processing of milk. This study also suggests that producers should improve the awareness of the protective effects of bioactive proteins in raw milk.
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Affiliation(s)
- Haoming Wu
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Yang Wang
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Qianqian Yao
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Linlin Fan
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Lu Meng
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Nan Zheng
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Huiying Li
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Jiaqi Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
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21
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Kang MW, Chen D, Ruan R, Vickers ZM. The effect of intense pulsed light on the sensory properties of nonfat dry milk. J Food Sci 2021; 86:4119-4133. [PMID: 34383322 DOI: 10.1111/1750-3841.15865] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 06/09/2021] [Accepted: 07/02/2021] [Indexed: 11/30/2022]
Abstract
Our objectives were to examine (1) how intense pulsed light (IPL) processing parameters (exposure time and initial temperature) affected aroma, flavor, and mouthfeel of nonfat dry milk, (2) which levels of each parameter produced aroma, flavor, and mouthfeel changes from an untreated control sample, and (3) whether minimal or intense processing conditions produced a noticeable appearance change from the control. Four exposure times (1, 2, 3, and 4 passes through the IPL chamber) and three initial temperatures (25, 30, and 35℃) were studied with untreated milk powder as the control. The samples were prepared as both milk powder and reconstituted milk for sensory evaluation. Using standard evaluating protocols, trained descriptive analysis panelists rated the aroma, flavor, and mouthfeel of these samples. Panelists compared the appearance of the IPL-treated samples that underwent a minimal or intense processing condition to the control by using a two-out-of-five difference test. Increasing the exposure time led to increased intensities of overall flavor, burnt flavor, and umami taste in both milk powder and reconstituted milk, while increasing temperature increased animal and sulfur aromas in reconstituted milk only. Compared to the control, all levels of exposure time at any initial temperature resulted in increased aroma and flavor including cardboard aroma, sulfur aroma, and brothy flavor in both milk powder and reconstituted milk. Only the 4-pass exposure at the initial temperature of 25℃ changed the appearance of milk powder. However, the appearance change was not noticeable in reconstituted milk. PRACTICAL APPLICATION: The standard evaluation protocols and lexicons provide useful tools for research on milk powder. Additionally, the understanding of critical factors impacting sensory properties will contribute to a better implementation of this decontamination technology.
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Affiliation(s)
- Myung-Woo Kang
- Department of Food Science and Nutrition, University of Minnesota, Saint Paul, Minnesota, USA
| | - Dongjie Chen
- Department of Food Science and Nutrition, University of Minnesota, Saint Paul, Minnesota, USA
| | - Roger Ruan
- Department of Food Science and Nutrition, University of Minnesota, Saint Paul, Minnesota, USA
| | - Zata M Vickers
- Department of Food Science and Nutrition, University of Minnesota, Saint Paul, Minnesota, USA
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22
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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.
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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;
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23
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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: 7] [Impact Index Per Article: 2.3] [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.
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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.
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24
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Berthold-Pluta A, Garbowska M, Stefańska I, Stasiak-Różańska L, Aleksandrzak-Piekarczyk T, Pluta A. Microbiological Quality of Nuts, Dried and Candied Fruits, Including the Prevalence of Cronobacter spp. Pathogens 2021; 10:900. [PMID: 34358048 PMCID: PMC8308658 DOI: 10.3390/pathogens10070900] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/13/2021] [Accepted: 07/14/2021] [Indexed: 11/21/2022] Open
Abstract
Cronobacter genus bacteria are food-borne pathogens. Foods contaminated with Cronobacter spp. may pose a risk to infants or immunocompromised adults. The aim of this study was to determine the microbiological quality of nuts, seeds and dried fruits with special emphasis on the occurrence of Cronobacter spp. Analyses were carried out on 64 samples of commercial nuts (20 samples), dried fruits (24), candied fruits (8), seeds (4), and mixes of seeds, dried fruits and nuts (8). The samples were tested for the total plate count of bacteria (TPC), counts of yeasts and molds, and the occurrence of Cronobacter spp. Cronobacter isolates were identified and differentiated by PCR-RFLP (Polymerase Chain Reaction - Restriction Fragments Length Polymorphism) and RAPD-PCR (Random Amplified Polymorphic DNA by PCR) analysis. TPC, and yeasts and molds were not detected in 0.1 g of 23.4%, 89.1%, and 32.8% of the analyzed samples. In the remaining samples, TPC were in the range of 1.2-5.3 log CFU g-1. The presence/absence of Cronobacter species was detected in 12 (18.8%) samples of: nuts (10 samples), and mixes (2 samples). The 12 strains of Cronobacter spp. included: C. sakazakii (3 strains), C. malonaticus (5), and C. turicensis (4). The results of this study contribute to the determination of the presence and species identification of Cronobacter spp. in products of plant origin intended for direct consumption.
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Affiliation(s)
- Anna Berthold-Pluta
- Department of Technology and Food Assessment, Division of Milk Technology, Institute of Food Sciences, Warsaw University of Life Sciences—SGGW, 02-787 Warsaw, Poland; (M.G.); (L.S.-R.); (A.P.)
| | - Monika Garbowska
- Department of Technology and Food Assessment, Division of Milk Technology, Institute of Food Sciences, Warsaw University of Life Sciences—SGGW, 02-787 Warsaw, Poland; (M.G.); (L.S.-R.); (A.P.)
| | - Ilona Stefańska
- Department of Preclinical Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences—SGGW, 02-787 Warsaw, Poland;
| | - Lidia Stasiak-Różańska
- Department of Technology and Food Assessment, Division of Milk Technology, Institute of Food Sciences, Warsaw University of Life Sciences—SGGW, 02-787 Warsaw, Poland; (M.G.); (L.S.-R.); (A.P.)
| | | | - Antoni Pluta
- Department of Technology and Food Assessment, Division of Milk Technology, Institute of Food Sciences, Warsaw University of Life Sciences—SGGW, 02-787 Warsaw, Poland; (M.G.); (L.S.-R.); (A.P.)
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25
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Bacterial Distribution, Biogenic Amine Contents, and Functionalities of Traditionally Made Doenjang, a Long-Term Fermented Soybean Food, from Different Areas of Korea. Microorganisms 2021; 9:microorganisms9071348. [PMID: 34206411 PMCID: PMC8304856 DOI: 10.3390/microorganisms9071348] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/15/2021] [Accepted: 06/18/2021] [Indexed: 12/16/2022] Open
Abstract
Since doenjang quality depends on the bacterial composition, which ambient bacteria in the environment and production conditions influence, a complete understanding of the bacteria community in traditionally madetraditionally made doenjang (TMD) from different regions is needed. We aimed to investigate the bacteria composition and quality of TMD in the following areas: Chonbuk (CB), Chonnam (CN), Kyungsang (KS), Kangwon (KW), Chungchung (CC) provinces, and Jeju island (JJ) of Korea. Twenty-nine TMD samples from different regions were used to assess biogenic amine contents, bacteria composition using next-generation methods, and metabolic functions of the bacteria using Picrust2. Bacillus spp. were isolated, and their antioxidant and fibrinolytic activities were determined. Most TMD contained high amounts of beneficial bacteria (Bacillus, Lactobacillus, Pediococcus and Weissella). However, some KS samples contained harmful bacteria (Cronobacter, Proteus and Acinetobacter) and less beneficial B. velezensis bacteria. There was no similarity among the regional groups, and each TMD showed a different bacteria composition. Shannon index, α-diversity index, was lower in TMD from JJ and CB than the other areas, but there was no β-diversity among TMD from the six area groups. Picrust2 analysis revealed that the functional potential for arachidonic acid metabolism was lowest in JJ and CN, that for supporting insulin action was highest in KS and JJ, and that for carbohydrate digestion and absorption was lowest in CB and JJ among all groups (p < 0.05) according to the Kyoto Encyclopedia of Genes and Genomes Orthology. Histamine contents were lower in CN and CC, and tyramine contents did not differ significantly. B. velezensis, B. subtilis, B. licheniformis, B. siamensis, and B. amyloliquefaciens were isolated from TMD. None of the isolated Bacillus spp. contained the B. cereus gene. B. subtilis from CN had the highest fibrinolytic activity, and B. velezensis from CB had the highest antioxidant activity. In conclusion, TMD mainly contained various Bacillus spp., and the predominant one was B. velezensis, which had antioxidant and fibrinolytic activity regardless of the regional origin.
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26
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Kim HR, Kim M, Kim BC. Specific detection of Cronobacter sakazakii in powdered infant formula using ssDNA aptamer. Analyst 2021; 146:3534-3542. [PMID: 33884389 DOI: 10.1039/d1an00118c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Cronobacter sakazakii (C. sakazakii) is a foodborne pathogen associated with bacterial meningitis, sepsis, and necrotizing enterocolitis in premature and immuno-compromised infants. C. sakazakii is typically acquired by ingesting contaminated powdered infant formula (PIF). The growing demand for a safe food supply requires rapid detection of foodborne pathogens for delivering safe-to-consume food to consumers. In the present study, we isolated C. sakazakii-specific aptamers using a centrifugation-based partitioning method (CBPM) instead of systematic evolution of ligands by exponential enrichment (SELEX) process. Unlike SELEX, the CBPM reduces the evolution-loop time to obtain enriched probes, allowing the isolation of target-specific aptamers in a shorter time. The two aptamers (SC25 and SC45) isolated using the CBPM showed high affinity and specificity for C. sakazakii (Kd: 34 and 66 nM). Among the two aptamers, SC25 aptamer detected efficiently C. sakazakii in PIF with less cross-reactivity. Our results indicate that the isolated aptamers could be used for detecting C. sakazakii in PIF and reducing the overall testing time compared with the conventional C. sakazakii detection method.
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Affiliation(s)
- Hye Ri Kim
- Center for Environment, Health and Welfare Research, Korea Institute of Science and Technology (KIST), Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Republic of Korea. and Division of Energy and Environment Technology, KIST School, University of Science and Technology (UST), Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Republic of Korea
| | - Myunghee Kim
- Department of Food Science and Technology, Yeungnam University, 280 Daehak-ro, Gyeongsan-si, Gyeongsangbuk-do 38541, Republic of Korea
| | - Byoung Chan Kim
- Center for Environment, Health and Welfare Research, Korea Institute of Science and Technology (KIST), Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Republic of Korea. and Division of Energy and Environment Technology, KIST School, University of Science and Technology (UST), Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792, Republic of Korea
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27
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Liu X, Qian M, Shen Y, Qin X, Huang H, Yang H, He Y, Bai W. An high-throughput sequencing approach to the preliminary analysis of bacterial communities associated with changes in amino acid nitrogen, organic acid and reducing sugar contents during soy sauce fermentation. Food Chem 2021; 349:129131. [PMID: 33581434 DOI: 10.1016/j.foodchem.2021.129131] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 12/25/2022]
Abstract
Soy sauce is a traditional fermented soy food for enhancing the umami taste in Asian cuisines. In this study, 16S rRNA gene throughput sequencing analysis showed the bacterial communities and the changes in soy sauce during fermentation. Weissella, Bacillus and Lactococcus were the most abundant at genus level. The uncultured bacterium Weissella and Lactococcus had relatively high abundance at species level. Alpha diversity analysis indicated the bacterial community diversity increased at fermentation initiation, while decreased as fermentation progressed. Based on beta-diversity analysis, four clusters including cluster I (time point A-F), cluster II (G,H), cluster III (I,J) and cluster IV(K) were distinctly separated, indicating the fermentation time significantly affected bacterial community diversity. Also, close associations were found between the bacterial communities in soy sauce and its amino acid nitrogen, organic acid and reducing sugar contents during fermentation. Therefore, it will provide important information for optimization of the soy sauce production process.
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Affiliation(s)
- Xiaoyan Liu
- College of Light Industry and Food, Zhongkai University of Agriculture and Engineering, Guangzhou, China; Key Laboratory of Cantonese Traditional Food Processing and Safety Control of Guangzhou, Guangzhou, China
| | - Min Qian
- College of Light Industry and Food, Zhongkai University of Agriculture and Engineering, Guangzhou, China; Key Laboratory of Cantonese Traditional Food Processing and Safety Control of Guangzhou, Guangzhou, China
| | - Yixiao Shen
- College of Food Science Shenyang Agricultural University, Shenyang, China
| | - Xuan Qin
- College of Light Industry and Food, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Hancong Huang
- Guangzhou Rufeng Fruit Seasoning Food Co., Ltd., Guangzhou, China
| | - Hong Yang
- College of Light Industry and Food, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Yilong He
- College of Light Industry and Food, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Weidong Bai
- College of Light Industry and Food, Zhongkai University of Agriculture and Engineering, Guangzhou, China; Key Laboratory of Cantonese Traditional Food Processing and Safety Control of Guangzhou, Guangzhou, China.
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28
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Ke A, Parreira VR, Goodridge L, Farber JM. Current and Future Perspectives on the Role of Probiotics, Prebiotics, and Synbiotics in Controlling Pathogenic Cronobacter Spp. in Infants. Front Microbiol 2021; 12:755083. [PMID: 34745060 PMCID: PMC8567173 DOI: 10.3389/fmicb.2021.755083] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 09/27/2021] [Indexed: 12/14/2022] Open
Abstract
Cronobacter species, in particular C. sakazakii, is an opportunistic bacterial pathogen implicated in the development of potentially debilitating illnesses in infants (<12months old). The combination of a poorly developed immune system and gut microbiota put infants at a higher risk of infection compared to other age groups. Probiotics and prebiotics are incorporated in powdered infant formula and, in addition to strengthening gut physiology and stimulating the growth of commensal gut microbiota, have proven antimicrobial capabilities. Postbiotics in the cell-free supernatant of a microbial culture are derived from probiotics and can also exert health benefits. Synbiotics, a mixture of probiotics and prebiotics, may provide further advantages as probiotics and gut commensals degrade prebiotics into short-chain fatty acids that can provide benefits to the host. Cell-culture and animal models have been widely used to study foodborne pathogens, but sophisticated gut models have been recently developed to better mimic the gut conditions, thus giving a more accurate representation of how various treatments can affect the survival and pathogenicity of foodborne pathogens. This review aims to summarize the current understanding on the connection between Cronobacter infections and infants, as well as highlight the potential efficacy of probiotics, prebiotics, and synbiotics in reducing invasive Cronobacter infections during early infancy.
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29
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Polat Yemiş G, Delaquis P. Natural Compounds With Antibacterial Activity Against Cronobacter spp. in Powdered Infant Formula: A Review. Front Nutr 2020; 7:595964. [PMID: 33330595 PMCID: PMC7731913 DOI: 10.3389/fnut.2020.595964] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 10/08/2020] [Indexed: 12/15/2022] Open
Abstract
Bacteria from the genus Cronobacter are opportunistic foodborne pathogens capable of causing severe infections in neonates, the elderly and immunocompromised adults. The majority of neonatal infections have been linked epidemiologically to dehydrated powdered infant formulas (PIFs), the majority of which are manufactured using processes that do not ensure commercial sterility. Unfortunately, the osmotolerance, desiccation resistance, mild thermotolerance and wide-ranging minimum, optimum and maximum growth temperatures of Cronobacter spp. are conducive to survival and/or growth during the processing, reconstitution and storage of reconstituted PIFs. Consequently, considerable research has been directed at the development of alternative strategies for the control of Cronobacter spp. in PIFs, including approaches that employ antimicrobial compounds derived from natural sources. The latter include a range of phytochemicals ranging from crude extracts or essential oils derived from various plants (e.g., thyme, cinnamon, clove, marjoram, cumin, mint, fennel), to complex polyphenolic extracts (e.g., muscadine seed, pomegranate peel, olive oil, and cocoa powder extracts), purified simple phenolic compounds (e.g., carvacrol, citral, thymol, eugenol, diacetyl, vanillin, cinnamic acid, trans-cinnamaldehyde, ferulic acid), and medium chain fatty acids (monocaprylin, caprylic acid). Antimicrobials derived from microbial sources (e.g., nisin, other antibacterial peptides, organic acids, coenzyme Q0) and animal sources (e.g., chitosan, lactoferrin, antibacterial peptides from milk) have also been shown to exhibit antibacterial activity against the species. The selection of antimicrobials for the control of Cronobacter spp. requires an understanding of activity at different temperatures, knowledge about their mode of action, and careful consideration for toxicological and nutritional effects on neonates. Consequently, the purpose of the present review is to provide a comprehensive summary of currently available data pertaining to the antibacterial effects of natural antimicrobial compounds against Cronobacter spp. with a view to provide information needed to inform the selection of compounds suitable for control of the pathogen during the manufacture or preparation of PIFs by end users.
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Affiliation(s)
- Gökçe Polat Yemiş
- Department of Food Engineering, Sakarya University, Serdivan, Turkey
| | - Pascal Delaquis
- Summerland Research and Development Research Centre, Agriculture and AgriFood Canada, Summerland, BC, Canada
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Abstract
Mycobacterium avium paratuberculosis is responsible for paratuberculosis or Johne's disease in cows, having economic impacts on the dairy industry and a prevalence rate exceeding 50% in dairy herds. The economic burden of Johne's disease relates to decreased milk production and costs of disease prevention, treatment, and management, while having an economic impact on dairy producers, processors, consumers, and stakeholders of the dairy industry. Determining the true economic impact of the disease is difficult at regional and farm level as symptoms are not evident in subclinically infected animals. At present, the virulence, pathogenicity, persistence, and infectious dose of M. avium paratuberculosis are poorly understood, consequently effective paratuberculosis control measures remain obscure. M. avium paratuberculosis is potentially zoonotic with foodborne transmission a public health risk due to a possible causative link with inflammatory bowel disease in humans. A preventive approach is necessary to reduce the presence of this drug-resistant pathogen in dairy herds and subsequently dairy food. The use of inefficient diagnostic tests coupled with the long latency period of infection results in delayed animal culling and trade of asymptomatic animals, leading to regional transmission and increased disease prevalence. To date, there has been limited success at controlling and treating this terminal endemic disease, leading to significant prevalence rates. This study aims to outline the key factors associated with Johne's' disease while outlining its significant impact on the dairy sector.
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Affiliation(s)
- Mary Garvey
- Department of Life Science, Sligo Institute of Technology, F91 YW50 Sligo, Ireland
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31
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Mycobacterium Avium Paratuberculosis: A Disease Burden on the Dairy Industry. Animals (Basel) 2020; 10:ani10101773. [PMID: 33019502 PMCID: PMC7601789 DOI: 10.3390/ani10101773] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 09/21/2020] [Accepted: 09/26/2020] [Indexed: 12/22/2022] Open
Abstract
Mycobacterium avium paratuberculosis is responsible for paratuberculosis or Johne's disease in cows, having economic impacts on the dairy industry and a prevalence rate exceeding 50% in dairy herds. The economic burden of Johne's disease relates to decreased milk production and costs of disease prevention, treatment, and management, while having an economic impact on dairy producers, processors, consumers, and stakeholders of the dairy industry. Determining the true economic impact of the disease is difficult at regional and farm level as symptoms are not evident in subclinically infected animals. At present, the virulence, pathogenicity, persistence, and infectious dose of M. avium paratuberculosis are poorly understood, consequently effective paratuberculosis control measures remain obscure. M. avium paratuberculosis is potentially zoonotic with foodborne transmission a public health risk due to a possible causative link with inflammatory bowel disease in humans. A preventive approach is necessary to reduce the presence of this drug-resistant pathogen in dairy herds and subsequently dairy food. The use of inefficient diagnostic tests coupled with the long latency period of infection results in delayed animal culling and trade of asymptomatic animals, leading to regional transmission and increased disease prevalence. To date, there has been limited success at controlling and treating this terminal endemic disease, leading to significant prevalence rates. This study aims to outline the key factors associated with Johne's' disease while outlining its significant impact on the dairy sector.
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32
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The role of the general stress response regulator RpoS in Cronobacter sakazakii biofilm formation. Food Res Int 2020; 136:109508. [DOI: 10.1016/j.foodres.2020.109508] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 06/25/2020] [Accepted: 06/28/2020] [Indexed: 11/20/2022]
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33
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Ripolles-Avila C, Martínez-Garcia M, Capellas M, Yuste J, Fung DYC, Rodríguez-Jerez JJ. From hazard analysis to risk control using rapid methods in microbiology: A practical approach for the food industry. Compr Rev Food Sci Food Saf 2020; 19:1877-1907. [PMID: 33337076 DOI: 10.1111/1541-4337.12592] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 05/14/2020] [Accepted: 05/15/2020] [Indexed: 12/14/2022]
Abstract
The prevention of foodborne diseases is one of the main objectives of health authorities. To this effect, analytical techniques to detect and/or quantify the microbiological contamination of foods prior to their release onto the market are required. Management and control of foodborne pathogens have generally been based on conventional detection methodologies, which are not only time-consuming and labor-intensive but also involve high consumable materials costs. However, this management perspective has changed over time given that the food industry requires efficient analytical methods that obtain rapid results. This review covers the historical context of traditional methods and their passage in time through to the latest developments in rapid methods and their implementation in the food sector. Improvements and limitations in the detection of the most relevant pathogens are discussed from a perspective applicable to the current situation in the food industry. Considering efforts that are being done and recent developments, rapid and accurate methods already used in the food industry will be also affordable and portable and offer connectivity in near future, which improves decision-making and safety throughout the food chain.
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Affiliation(s)
- Carolina Ripolles-Avila
- Area of Human Nutrition and Food Science, Departament de Ciència Animal i dels Aliments, Facultat de Veterinària, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Maria Martínez-Garcia
- Area of Human Nutrition and Food Science, Departament de Ciència Animal i dels Aliments, Facultat de Veterinària, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Marta Capellas
- Area of Food Technology, Departament de Ciència Animal i dels Aliments, Facultat de Veterinària, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Josep Yuste
- Area of Food Technology, Departament de Ciència Animal i dels Aliments, Facultat de Veterinària, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Daniel Y C Fung
- Call Hall, Department of Animal Sciences and Industry, Kansas State University, Manhattan, Kansas
| | - José-Juan Rodríguez-Jerez
- Area of Human Nutrition and Food Science, Departament de Ciència Animal i dels Aliments, Facultat de Veterinària, Universitat Autònoma de Barcelona, Barcelona, Spain
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Ripolles‐Avila C, Ríos‐Castillo AG, Fontecha‐Umaña F, Rodríguez‐Jerez JJ. Removal of
Salmonella enterica
serovar Typhimurium and
Cronobacter sakazakii
biofilms from food contact surfaces through enzymatic catalysis. J Food Saf 2020. [DOI: 10.1111/jfs.12755] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Carolina Ripolles‐Avila
- Area of Human Nutrition and Food Sciences, Departament de Ciència Animal i dels Aliments, Facultat de VeterinariaUniversitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), CP 08193 Barcelona Spain
| | - Abel G. Ríos‐Castillo
- Area of Human Nutrition and Food Sciences, Departament de Ciència Animal i dels Aliments, Facultat de VeterinariaUniversitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), CP 08193 Barcelona Spain
| | - Fabio Fontecha‐Umaña
- Area of Human Nutrition and Food Sciences, Departament de Ciència Animal i dels Aliments, Facultat de VeterinariaUniversitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), CP 08193 Barcelona Spain
| | - José J. Rodríguez‐Jerez
- Area of Human Nutrition and Food Sciences, Departament de Ciència Animal i dels Aliments, Facultat de VeterinariaUniversitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), CP 08193 Barcelona Spain
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Elkhawaga AA, Hetta HF, Osman NS, Hosni A, El-Mokhtar MA. Emergence of Cronobacter sakazakii in Cases of Neonatal Sepsis in Upper Egypt: First Report in North Africa. Front Microbiol 2020; 11:215. [PMID: 32210926 PMCID: PMC7075355 DOI: 10.3389/fmicb.2020.00215] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 01/30/2020] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND AND AIM Cronobacter sakazakii (C. sakazakii) has attracted considerable attention as an emerging neonatal pathogen and has been associated with outbreaks of life-threatening septicemia, necrotizing enterocolitis, and meningitis in neonates and infants globally. No data about the role of C. sakazakii as a cause of neonatal sepsis in North Africa is availale. Herein, we aimed to study the incidence of C. sakazakii in cases of neonatal sepsis, its distribution in different food samples in Egypt, antimicrobial profile, and the ability of the strains to form biofilms. METHODS A total of 100 positive blood cultures from cases of neonatal sepsis admitted to the neonatal ICU at Assiut University Children's Hospital, Egypt, were analyzed. In addition, 1,100 food samples, including 400 powdered infant formula (PIF), 500 herbs, and 200 water samples were screened for the presence of C. sakazakii. We evaluated the antimicrobial profile and the ability of the strains to form biofilms. RESULTS Cronobacter sakazakii was detected in 12 out of 100 cases of neonatal sepsis. The organism was also isolated from PIF, herbs, and water in percentages of 17.5, 9.2, and 7.5%, respectively. Regarding the antimicrobial sensitivity, all strains were resistant to ampicillin, amoxicillin, ampicillin/sulbactam, clindamycin, cephalothin, and cephalexin. In addition, C. sakazakii strains showed the ability to form biofilms, but with variable degrees of cell density. CONCLUSION We reported, for the first time, cases of neonatal sepsis caused by the emerging life-threatening pathogen C. sakazakii in Egypt. The organism was also detected in contaminated PIF, herbs, and water, which may be sources of infection for neonates, especially in countries where natural herbs are widely used as an alternative medicine. Finally, collective efforts by the parents, manufacturers of PIF, and healthcare personnel are essential to prevent serious infections caused by C. sakazakii, particularly in infants.
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Affiliation(s)
- Amal A. Elkhawaga
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Helal F. Hetta
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt
- Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Naglaa S. Osman
- Department of Pediatrics, Children’s Hospital, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Amal Hosni
- Department of Clinical Pathology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Mohamed A. El-Mokhtar
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt
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36
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Wang M, Wang L, Wu P, Chen T, Zhu Y, Zhang Y, Wei Y, Qian C, Wang Y, Liu B. Genomics and Experimental Analysis Reveal a Novel Factor Contributing to the Virulence of Cronobacter sakazakii Strains Associated With Neonate Infection. J Infect Dis 2020; 220:306-315. [PMID: 30835279 DOI: 10.1093/infdis/jiz098] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 03/02/2019] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Cronobacter sakazakii causes meningitis and necrotizing enterocolitis in premature infants. However, its virulence determinants, especially those specific for strains associated with neonate infections, remain largely unknown. METHODS In this study, we performed a comparative genomic analysis of 209 C. sakazakii genomes, and 8 clonal groups (CGs) were revealed. RESULTS CG1 and CG2 were found to be significantly associated with neonate infections, and significantly prevalent genes in these 2 CGs were identified. Of these, a gene encoding the LysR-type regulator, CklR, was shown to contribute to bacterial pathogenicity based on animal experiments. We found that CklR directly binds and activates the suf Fe-S cluster biosynthesis operon, and high expression of the suf operon increases bacterial resistance to oxidative stress, which increases survival within the host. This leads to a high degree of bacteremia, which contributes to the development of meningitis. CONCLUSIONS Our work revealed a novel virulence factor specific to predominant pathogenic C. sakazakii strains.
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Affiliation(s)
- Min Wang
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People's Republic of China.,TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People's Republic of China.,Center for Microbial Functional Genomics and Detection Technology, Ministry of Education, Tianjin, People's Republic of China.,Tianjin Key Laboratory of Microbial Functional Genomics, People's Republic of China
| | - Lu Wang
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People's Republic of China.,TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People's Republic of China
| | - Pan Wu
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People's Republic of China.,TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People's Republic of China
| | - Tingting Chen
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People's Republic of China.,TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People's Republic of China
| | - Yiming Zhu
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People's Republic of China.,TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People's Republic of China
| | - Yang Zhang
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People's Republic of China.,TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People's Republic of China
| | - Yi Wei
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People's Republic of China.,TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People's Republic of China
| | - Chengqian Qian
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People's Republic of China.,TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People's Republic of China
| | - Yuhui Wang
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People's Republic of China.,TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People's Republic of China
| | - Bin Liu
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People's Republic of China.,TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People's Republic of China.,Center for Microbial Functional Genomics and Detection Technology, Ministry of Education, Tianjin, People's Republic of China.,Tianjin Key Laboratory of Microbial Functional Genomics, People's Republic of China
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37
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Song JR, Fu YW, Li P, Du T, Du XJ, Wang S. Protective Effect of Recombinant Proteins of Cronobacter Sakazakii During Pregnancy on the Offspring. Front Cell Infect Microbiol 2020; 10:15. [PMID: 32076598 PMCID: PMC7006456 DOI: 10.3389/fcimb.2020.00015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 01/13/2020] [Indexed: 01/14/2023] Open
Abstract
Cronobacter sakazakii is a food-borne pathogen carried in milk powder that can cause severe bacteremia, enterocolitis, and meningitis in newborns, which can lead to death of newborns. Preventing infection by this pathogen is significant to the health of newborns. Since infants and young children are the main target group of C. sakazakii, it is considered that maternal immunity can enhance the protection of newborns. Previous studies showed that two proteins of C. sakazakii (GroEL and OmpX) exhibited high expression levels and elicited strong immune reactions, suggesting their potential as vaccine candidates. In this study, GroEL and OmpX were recombinantly expressed in Escherichia coli and purified as immunogens to immunize pregnant rats. Three days after birth, the progeny were challenged with C. sakazakii to determine the protective effect of maternal immunity on the offspring. The results showed that immunization during pregnancy decreased bacterial load in the brain and blood, reduced brain and intestine damage, and significantly increased specific antibody titers in the offspring. Immunization with the recombinant proteins significantly increased cytokine levels in the serum of the progeny. The group whose mothers were immunized with OmpX produced more IL-4, while the group whose mothers were immunized with GroEL produced more IFN-γ, indicating that the immunogens enhanced the Th2 and Th1 responses, respectively. However, although the immune response was induced by both proteins, only the offspring of the pregnant rats immunized with OmpX or OmpX/GroEL mixture showed delayed death, possibly because immunization with OmpX led to a stronger humoral immune response in the offspring, suggesting that OmpX was a better vaccine candidate than GroEL. This study first reported that exposure to C. sakazakii proteins during pregnancy could improve the offspring's ability to resist infection caused by this pathogen.
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Affiliation(s)
- Jia-Rong Song
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin, China
| | - Yan-Wen Fu
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin, China
| | - Ping Li
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin, China
| | - Ting Du
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin, China
| | - Xin-Jun Du
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin, China
| | - Shuo Wang
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin, China.,Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University, Tianjin, China
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38
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Xu C, Zhu H, Qiu P. Aging progression of human gut microbiota. BMC Microbiol 2019; 19:236. [PMID: 31660868 PMCID: PMC6819604 DOI: 10.1186/s12866-019-1616-2] [Citation(s) in RCA: 140] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 10/17/2019] [Indexed: 02/07/2023] Open
Abstract
Background Human gut microbiota are important for human health and have been regarded as a “forgotten organ”, whose variation is closely linked with various factors, such as host genetics, diet, pathological conditions and external environment. The diversity of human gut microbiota has been correlated with aging, which was characterized by different abundance of bacteria in various age groups. In the literature, most of the previous studies of age-related gut microbiota changes focused on individual species in the gut community with supervised methods. Here, we aimed to examine the underlying aging progression of the human gut microbial community from an unsupervised perspective. Results We obtained raw 16S rRNA sequencing data of subjects ranging from newborns to centenarians from a previous study, and summarized the data into a relative abundance matrix of genera in all the samples. Without using the age information of samples, we applied an unsupervised algorithm to recapitulate the underlying aging progression of microbial community from hosts in different age groups and identify genera associated to this progression. Literature review of these identified genera indicated that for individuals with advanced ages, some beneficial genera are lost while some genera related with inflammation and cancer increase. Conclusions The multivariate unsupervised analysis here revealed the existence of a continuous aging progression of human gut microbiota along with the host aging process. The identified genera associated to this aging process are meaningful for designing probiotics to maintain the gut microbiota to resemble a young age, which hopefully will lead to positive impact on human health, especially for individuals in advanced age groups.
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Affiliation(s)
- Congmin Xu
- Department of Biomedical Engineering, College of Engineering, Peking University, Beijing, 100871, China.,Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, 30332, USA
| | - Huaiqiu Zhu
- Department of Biomedical Engineering, College of Engineering, Peking University, Beijing, 100871, China
| | - Peng Qiu
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, 30332, USA.
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Chen D, Wiertzema J, Peng P, Cheng Y, Liu J, Mao Q, Ma Y, Anderson E, Chen P, Baumler DJ, Chen C, Vickers Z, Feirtag J, Lee L, Ruan R. Effects of intense pulsed light on Cronobacter sakazakii inoculated in non-fat dry milk. J FOOD ENG 2018. [DOI: 10.1016/j.jfoodeng.2018.06.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Nutritionally, the first 1,000 days of an infant's life - from conception to two years - has been identified as a highly influential period, during which lasting health can be achieved. Significant evidence links patterns of infant feeding to both short and long-term health outcomes, many of which can be prevented through nutritional modifications. Recommended globally, breastfeeding is recognised as the gold standard of infant nutrition; providing key nutrients to achieve optimal health, growth and development, and conferring immunologic protective effects against disease. Nevertheless, infant formulas are often the sole source of nutrition for many infants during the first stage of life. Producers of infant formula strive to supply high quality, healthy, safe alternatives to breast milk with a comparable balance of nutrients to human milk imitating its composition and functional performance measures. The concept of 'nutritional programming', and the theory that exposure to specific conditions, can predispose an individual's health status in later life has become an accepted dictum, and has sparked important nutritional research prospects. This review explores the impact of early life nutrition, specifically, how different feeding methods affect health outcomes.
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Affiliation(s)
- Susan Finn
- Nutrition and Health Science from Cork Institute of Technology
| | | | | | - Roy D. Sleator
- University College Cork and National University of Ireland
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41
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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.
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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
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42
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Tutar E, Akıncı KS, Akyol İ. Development and application of a new multiplex real-time PCR assay for simultaneous identification of Brucella melitensis
, Cronobacter sakazakii
and Listeria monocytogenes
in raw milk and cheese. INT J DAIRY TECHNOL 2018. [DOI: 10.1111/1471-0307.12500] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Esen Tutar
- Science and Letters Faculty; Kahramanmaraş Sütçü İmam University; 46060/Avşar Campus Kahramanmaraş Turkey
| | - Kübra Sueda Akıncı
- Health Sciences University; Health Sciences Faculty; Department of Nutrition and Dietetics; 34668/Üsküdar İstanbul Turkey
| | - İsmaİl Akyol
- Agricultural Biotechnology Department; Agriculture Faculty; Kahramanmaraş Sütçü İmam University; 46060/Avşar Campus Kahramanmaraş Turkey
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43
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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.
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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
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44
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Shi L, Liang Q, Zhan Z, Feng J, Zhao Y, Chen Y, Huang M, Tong Y, Wu W, Chen W, Li X, Yin Z, Wang J, Zhou D. Co-occurrence of 3 different resistance plasmids in a multi-drug resistant Cronobacter sakazakii isolate causing neonatal infections. Virulence 2017; 9:110-120. [PMID: 28771073 PMCID: PMC5955447 DOI: 10.1080/21505594.2017.1356537] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Cronobacter sakazakii 505108 was isolated from a sputum specimen of a neonate with severe pneumonia. C. sakazakii 505108 co-harbors 3 resistance plasmids of the IncHI2, IncX3, and IncFIB incomparability groups, respectively. These 3 plasmids have acquired several accessory modules, which carry an extremely large number of resistance genes, especially including those involved in resistance to carbapenems, aminoglycoside, tetracyclines, and phenicols and sulphonamide/trimethoprim. These plasmid-borne antibiotic resistance genes were associated with insertion sequences, integrons, and transposons, indicating that the assembly and mobilization of the corresponding accessory modules with complex chimera structures are facilitated by transposition and/or homologous recombination. This is the first report of fully sequence plasmids in clinical Cronobacter, which provides a deeper insight into plasmid-mediated multi-drug resistance in Cronobacter from hospital settings.
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Affiliation(s)
- Lining Shi
- a Institute of Medical Laboratory Sciences, Jinling Hospital, School of Medicine, Nanjing University , Nanjing , China
| | - Quanhui Liang
- b Department of Clinical Laboratory , The First People's Hospital of Foshan , Foshan , China
| | - Zhe Zhan
- c State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology , Beijing , China
| | - Jiao Feng
- c State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology , Beijing , China
| | - Yachao Zhao
- c State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology , Beijing , China
| | - Yong Chen
- a Institute of Medical Laboratory Sciences, Jinling Hospital, School of Medicine, Nanjing University , Nanjing , China
| | - Mei Huang
- a Institute of Medical Laboratory Sciences, Jinling Hospital, School of Medicine, Nanjing University , Nanjing , China
| | - Yigang Tong
- c State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology , Beijing , China
| | - Weili Wu
- d Beijing Institute of Genomics, Chinese Academy of Sciences , Beijing , China
| | - Weijun Chen
- d Beijing Institute of Genomics, Chinese Academy of Sciences , Beijing , China
| | - Xiaojun Li
- a Institute of Medical Laboratory Sciences, Jinling Hospital, School of Medicine, Nanjing University , Nanjing , China
| | - Zhe Yin
- c State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology , Beijing , China
| | - Jinglin Wang
- b Department of Clinical Laboratory , The First People's Hospital of Foshan , Foshan , China
| | - Dongsheng Zhou
- c State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology , Beijing , China
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Study of Cronobacter sakazakii Strains Isolated from Powdered Milk Infant Formula by Phenotypic and Molecular Methods in Iran. ARCHIVES OF PEDIATRIC INFECTIOUS DISEASES 2016. [DOI: 10.5812/pedinfect.38867] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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46
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Abstract
The review centers on the human gastrointestinal tract; focusing first on the bacterial stress responses needed to overcome the physiochemical defenses of the host, specifically how these stress survival strategies can be used as targets for alternative infection control strategies. The concluding section focuses on recent developments in molecular diagnostics; centring on the shifting paradigm from culture to molecular based diagnostics.
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Affiliation(s)
- Roy D Sleator
- a Department of Biological Sciences ; Cork Institute of Technology ; Bishopstown , Cork , Ireland
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47
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Feeney A, Sleator RD. Functional Screening of the Cronobacter sakazakii BAA-894 Genome reveals a role for ProP (ESA_02131) in carnitine uptake. Bioengineered 2015; 6:161-5. [PMID: 25915804 PMCID: PMC4601511 DOI: 10.1080/21655979.2015.1043500] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 04/06/2015] [Accepted: 04/16/2015] [Indexed: 01/16/2023] Open
Abstract
Cronobacter sakazakii is a neonatal pathogen responsible for up to 80% of fatalities in infected infants. Low birth weight infants and neonates infected with C. sakazakii suffer necrotizing enterocolitis, bacteraemia and meningitis. The mode of transmission most often associated with infection is powdered infant formula (PIF) which, with an aw of ∼0.2, is too low to allow most microorganisms to persist. Survival of C. sakazakii in environments subject to extreme hyperosmotic stress has previously been attributed to the uptake of compatible solutes including proline and betaine. Herein, we report the construction and screening of a C. sakazakii genome bank and the identification of ProP (ESA_02131) as a carnitine uptake system.
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Affiliation(s)
- Audrey Feeney
- 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
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