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Zhu D, Fan Y, Wang X, Li P, Huang Y, Jiao J, Zhao C, Li Y, Wang S, Du X. Characterization of Molecular Chaperone GroEL as a Potential Virulence Factor in Cronobacter sakazakii. Foods 2023; 12:3404. [PMID: 37761113 PMCID: PMC10528849 DOI: 10.3390/foods12183404] [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: 08/15/2023] [Revised: 09/04/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
The molecular chaperone GroEL of C. sakazakii, a highly conserved protein encoded by the gene grol, has the basic function of responding to heat shock, thus enhancing the bacterium's adaptation to dry and high-temperature environments, which poses a threat to food safety and human health. Our previous study demonstrated that GroEL was found in the bacterial membrane fraction and caused a strong immune response in C. sakazakii. In this study, we tried to elucidate the subcellular location and virulent effects of GroEL. In live C. sakazakii cells, GroEL existed in both the soluble and insoluble fractions. To study the secretory mechanism of GroEL protein, a non-reduced Western immunoblot was used to analyze the form of the protein, and the result showed that the exported GroEL protein was mainly in monomeric form. The exported GroEL could also be located on bacterial surface. To further research the virulent effect of C. sakazakii GroEL, an indirect immunofluorescence assay was used to detect the adhesion of recombinant GroEL protein to HCT-8 cells. The results indicated that the recombinant GroEL protein could adhere to HCT-8 cells in a short period of time. The recombinant GroEL protein could activate the NF-κB signaling pathway to release more pro-inflammatory cytokines (TNF-α, IL-6 and IL-8), downregulating the expression of tight-junction proteins (claudin-1, occluding, ZO-1 and ZO-2), which collectively resulted in dose-dependent virulent effects on host cells. Inhibition of the grol gene expression resulted in a significant decrease in bacterial adhesion to and invasion of HCT-8 cells. Moreover, the deficient GroEL also caused slow growth, decreased biofilm formation, defective motility and abnormal filamentation of the bacteria. In brief, C. sakazakii GroEL was an important virulence factor. This protein was not only crucial for the physiological activity of C. sakazakii but could also be secreted to enhance the bacterium's adhesion and invasion capabilities.
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Affiliation(s)
- 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; (D.Z.); (Y.F.); (X.W.); (P.L.); (Y.H.); (J.J.); (C.Z.); (Y.L.); (S.W.)
| | - 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; (D.Z.); (Y.F.); (X.W.); (P.L.); (Y.H.); (J.J.); (C.Z.); (Y.L.); (S.W.)
| | - Xiaoyi Wang
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China; (D.Z.); (Y.F.); (X.W.); (P.L.); (Y.H.); (J.J.); (C.Z.); (Y.L.); (S.W.)
| | - 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; (D.Z.); (Y.F.); (X.W.); (P.L.); (Y.H.); (J.J.); (C.Z.); (Y.L.); (S.W.)
| | - Yaping Huang
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China; (D.Z.); (Y.F.); (X.W.); (P.L.); (Y.H.); (J.J.); (C.Z.); (Y.L.); (S.W.)
| | - 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; (D.Z.); (Y.F.); (X.W.); (P.L.); (Y.H.); (J.J.); (C.Z.); (Y.L.); (S.W.)
| | - 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; (D.Z.); (Y.F.); (X.W.); (P.L.); (Y.H.); (J.J.); (C.Z.); (Y.L.); (S.W.)
| | - Yue Li
- State Key Laboratory of Food Nutrition and Safety, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China; (D.Z.); (Y.F.); (X.W.); (P.L.); (Y.H.); (J.J.); (C.Z.); (Y.L.); (S.W.)
| | - 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; (D.Z.); (Y.F.); (X.W.); (P.L.); (Y.H.); (J.J.); (C.Z.); (Y.L.); (S.W.)
- 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; (D.Z.); (Y.F.); (X.W.); (P.L.); (Y.H.); (J.J.); (C.Z.); (Y.L.); (S.W.)
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2
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Chechi JL, Rotchanapreeda T, da Paz GS, Prado AC, Oliveira AL, Vieira JCS, Buzalaf MAR, Rodrigues AM, dos Santos LD, Krajaejun T, Bosco SDMG. Prospecting Biomarkers for Diagnostic and Therapeutic Approaches in Pythiosis. J Fungi (Basel) 2021; 7:jof7060423. [PMID: 34071174 PMCID: PMC8229905 DOI: 10.3390/jof7060423] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 05/04/2021] [Accepted: 05/05/2021] [Indexed: 12/11/2022] Open
Abstract
Pythiosis, whose etiological agent is the oomycete Pythium insidiosum, is a life-threatening disease that occurs mainly in tropical and subtropical countries, affecting several animal species. It is frequently found in horses in Brazil and humans in Thailand. The disease is difficult to diagnose because the pathogen’s hyphae are often misdiagnosed as mucoromycete fungi in histological sections. Additionally, there is no specific antigen to use for rapid diagnosis, the availability of which could improve the prognosis in different animal species. In this scenario, we investigated which P. insidiosum antigens are recognized by circulating antibodies in horses and humans with pythiosis from Brazil and Thailand, respectively, using 2D immunoblotting followed by mass spectrometry for the identification of antigens. We identified 23 protein spots, 14 recognized by pooled serum from horses and humans. Seven antigens were commonly recognized by both species, such as the heat-shock cognate 70 KDa protein, the heat-shock 70 KDa protein, glucan 1,3-beta-glucosidase, fructose-bisphosphate aldolase, serine/threonine-protein phosphatase, aconitate hydratase, and 14-3-3 protein epsilon. These results demonstrate that there are common antigens recognized by the immune responses of horses and humans, and these antigens may be studied as biomarkers for improving diagnosis and treatment.
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Affiliation(s)
- Jéssica Luana Chechi
- Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), Botucatu 18618-689, Brazil; (A.C.P.); (J.C.S.V.)
- Correspondence: (J.L.C.); (S.d.M.G.B.)
| | - Tiwa Rotchanapreeda
- Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand; (T.R.); (T.K.)
| | - Giselle Souza da Paz
- Faculty of Veterinary Medicine and Animal Science (FMVZ), São Paulo State University (UNESP), Botucatu 18618-681, Brazil; (G.S.d.P.); (A.L.O.)
| | - Ana Carolina Prado
- Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), Botucatu 18618-689, Brazil; (A.C.P.); (J.C.S.V.)
| | - Alana Lucena Oliveira
- Faculty of Veterinary Medicine and Animal Science (FMVZ), São Paulo State University (UNESP), Botucatu 18618-681, Brazil; (G.S.d.P.); (A.L.O.)
| | - José Cavalcante Souza Vieira
- Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), Botucatu 18618-689, Brazil; (A.C.P.); (J.C.S.V.)
| | - Marília Afonso Rabelo Buzalaf
- Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo (USP), Bauru 17012-901, Brazil;
| | - Anderson Messias Rodrigues
- Department of Microbiology, Immunology and Parasitology, Cell Biology Division, Federal University of São Paulo (UNIFESP), São Paulo 04023-062, Brazil;
| | - Lucilene Delazari dos Santos
- Center for the Study of Venoms and Venomous Animals (CEVAP), São Paulo State University (UNESP), Botucatu 18610-307, Brazil;
- Graduate Program in Tropical Diseases, Botucatu Medical School (FMB), São Paulo State University (UNESP), Botucatu 18618-687, Brazil
| | - Theerapong Krajaejun
- Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand; (T.R.); (T.K.)
| | - Sandra de Moraes Gimenes Bosco
- Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), Botucatu 18618-689, Brazil; (A.C.P.); (J.C.S.V.)
- Faculty of Veterinary Medicine and Animal Science (FMVZ), São Paulo State University (UNESP), Botucatu 18618-681, Brazil; (G.S.d.P.); (A.L.O.)
- Correspondence: (J.L.C.); (S.d.M.G.B.)
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Hu S, Yu Y, Lv Z, Shen J, Ke Y, Xiao X. Proteomics study unveils ROS balance in acid-adapted Salmonella Enteritidis. Food Microbiol 2020; 92:103585. [PMID: 32950169 DOI: 10.1016/j.fm.2020.103585] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 06/08/2020] [Accepted: 06/24/2020] [Indexed: 12/21/2022]
Abstract
Salmonella Enteritidis is a major cause of foodborne gastroenteritis and is thus a persistent threat to global public health. The acid adaptation response helps Salmonella survive exposure to gastric environment during ingestion. In a previous study we highlighted the damage caused to cell membrane and the regulation of intracellular reactive oxygen species (ROS) in S. Enteritidis. In this study, we applied both physiologic and iTRAQ analyses to explore the regulatory mechanism of acid resistance in Salmonella. It was found that after S. Enteritidis was subject to a 1 h period of acid adaptation at pH 5.5, an additional 1 h period of acid shock stress at pH 3.0 caused less Salmonella cell death than in non-acid adapted Salmonella cells. Although there were no significant differences between adapted and non-adapted cells in terms of cell membrane damage (e.g., membrane permeability or lipid peroxidation) after 30 min, intracellular ROS level in acid adapted cells was dramatically reduced compared to that in non-acid adapted cells, indicating that acid adaption promoted less ROS generation or increased the ability of ROS scavenging with little reduction in the integrity of the cell membrane. These findings were confirmed via an iTRAQ analysis. The adapted cells were shown to trigger incorporation of exogenous long-chain fatty acids into the cellular membrane, resulting in a different membrane lipid profile and promoting survival rate under acid stress. S. Enteritidis experiences oxidative damage and iron deficiency under acid stress, but after acid adaption S. Enteritidis cells were able to balance their concentrations of intracellular ROS. Specifically, SodAB consumed the free protons responsible for forming reactive oxygen intermediates (ROIs) and KatE protected cells from the toxic effects of ROIs. Additionally, acid-labile proteins released free unbound iron promoting ferroptotic metabolism, and NADH reduced GSSH to G-SH, protecting cells from acid/oxidative stress.
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Affiliation(s)
- Shuangfang Hu
- Key Laboratory of Molecular Epidemiology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen City, Guangdong Province, 518055, PR China; School of Food Science and Engineering, South China University of Technology, Guangzhou City, Guangdong Province, 510640, PR China; Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, 10083, PR China
| | - Yigang Yu
- School of Food Science and Engineering, South China University of Technology, Guangzhou City, Guangdong Province, 510640, PR China
| | - Ziquan Lv
- Key Laboratory of Molecular Epidemiology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen City, Guangdong Province, 518055, PR China
| | - Jianzhong Shen
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, 10083, PR China
| | - Yuebin Ke
- Key Laboratory of Molecular Epidemiology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen City, Guangdong Province, 518055, PR China.
| | - Xinglong Xiao
- School of Food Science and Engineering, South China University of Technology, Guangzhou City, Guangdong Province, 510640, PR China.
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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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5
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Zhao N, Liu JM, Liu S, Ji XM, Lv H, Hu YZ, Wang ZH, Lv SW, Li CY, Wang S. A novel universal nano-luciferase-involved reporter system for long-term probing food-borne probiotics and pathogenic bacteria in mice by in situ bioluminescence imaging. RSC Adv 2020; 10:13029-13036. [PMID: 35492135 PMCID: PMC9051406 DOI: 10.1039/d0ra01283a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 03/23/2020] [Indexed: 01/18/2023] Open
Abstract
Food-borne bacteria have received increasing attention due to their great impact on human health. Bioimaging makes it possible to monitor bacteria inside the living body in real time and in situ. Nano-luciferase (NLuc) as a new member of the luciferase family exhibits superior properties than the commonly used luciferases, including small size, high stability and improved luminescence. Herein, NLuc, CBRLuc and FLuc were well expressed in varied food-borne bacteria. Results showed that the signal intensity of E. coli-NLuc was about 41 times higher than E. coli-CBRLuc, L. plantarum-NLuc was nearly 227 times that of L. plantarum-FLuc in vitro. Moreover, NLuc was applied to trace L. plantarum and E. coli in vivo through the whole body and separated digestive tract imaging, as well as the feces bacterium counting and probing. The persistence of bioluminescent strains was predominantly localized in colon and cecum of mice after oral administration. The NLuc system showed its incomparable superiority, especially in the application of intestinal imaging and the universality for food-borne bacteria. We demonstrated that the NLuc system was a brilliant alternative for specific application of food-borne bacteria in vivo, aiming to collect more accurate and real-time information of food-borne bacteria from the living body for further investigation of their damage mechanism and nutrition effect. Schematic illustration of the preparation of bioluminescent bacteria and the experimental design of tracing of the foodborne bacteria in vivo.![]()
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Shi Y, Yue T, Zhang Y, Wei J, Yuan Y. Surface Immunoproteomics Reveals Potential Biomarkers in Alicyclobacillus acidoterrestris. Front Microbiol 2018; 9:3032. [PMID: 30564227 PMCID: PMC6288362 DOI: 10.3389/fmicb.2018.03032] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 11/23/2018] [Indexed: 11/21/2022] Open
Abstract
Alicyclobacillus acidoterrestris is a major putrefying bacterium that can cause pecuniary losses in the global juice industry. Current detection approaches are time-consuming and exhibit reduced specificity and sensitivity. In this study, an immunoproteomic approach was utilized to identify specific biomarkers from A. acidoterrestris for the development of new detection methods. Cell surface-associated proteins were extracted and separated by 2-D (two-dimensional) gel electrophoresis. Immunogenic proteins were detected by Western blot analysis using antisera against A. acidoterrestris. Twenty-two protein spots exhibiting immunogenicity were excised and eighteen of the associated spots were successfully identified by matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF/TOF MS). These proteins were observed to be involved in energy and carbohydrate metabolism, transmembrane transport, response to oxidative stress, polypeptide biosynthesis, and molecule binding activity. This is the first report detailing the identification of cell surface-associated antigens of A. acidoterrestris. The identified immunogenic proteins could serve as potential targets for the development of novel detection methods.
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Affiliation(s)
- Yiheng Shi
- College of Food Science and Engineering, Northwest A&F University, Yangling, China.,Laboratory of Quality and Safety Risk Assessment for Agro-Products, Ministry of Agriculture, Yangling, China.,National Engineering Research Center of Agriculture Integration Test, Yangling, China
| | - Tianli Yue
- College of Food Science and Engineering, Northwest A&F University, Yangling, China.,Laboratory of Quality and Safety Risk Assessment for Agro-Products, Ministry of Agriculture, Yangling, China.,National Engineering Research Center of Agriculture Integration Test, Yangling, China
| | - Yipei Zhang
- College of Food Science and Engineering, Northwest A&F University, Yangling, China.,Laboratory of Quality and Safety Risk Assessment for Agro-Products, Ministry of Agriculture, Yangling, China.,National Engineering Research Center of Agriculture Integration Test, Yangling, China
| | - Jianping Wei
- College of Food Science and Engineering, Northwest A&F University, Yangling, China.,Laboratory of Quality and Safety Risk Assessment for Agro-Products, Ministry of Agriculture, Yangling, China.,National Engineering Research Center of Agriculture Integration Test, Yangling, China
| | - Yahong Yuan
- College of Food Science and Engineering, Northwest A&F University, Yangling, China.,Laboratory of Quality and Safety Risk Assessment for Agro-Products, Ministry of Agriculture, Yangling, China.,National Engineering Research Center of Agriculture Integration Test, Yangling, China
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Comparative proteomic analysis of Cronobacter sakazakii by iTRAQ provides insights into response to desiccation. Food Res Int 2017; 100:631-639. [PMID: 28873731 DOI: 10.1016/j.foodres.2017.06.051] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 06/18/2017] [Accepted: 06/20/2017] [Indexed: 11/21/2022]
Abstract
Cronobacter sakazakii is a foodborne pathogen throughout the world and survives extremely desiccation stress. However, the molecular basis involved in desiccation resistance of C. sakazakii is still unknown. In this study, the potential desiccation resistance factors of C. sakazakii ATCC 29544 were determined using iTRAQ-based quantitative proteomic analysis. A total of 2775 proteins were identified by iTRAQ, of which 233 showed a different protein expression between control group and desiccation stress group. Among these 233 proteins identified as desiccation resistance proteins, there were 146 proteins downregulated and 87 proteins upregulated. According to the comprehensive proteome coverage analysis, C. sakazakii increased its resistance to desiccation by reducing the gene involved with unnecessary survival functions such as those used for virulence, adhesion, invasion and flagella assembly, while increasing gene expression of genes used in withstanding osmotic stress such as those genes involved in trehalose and betaine uptake. However, the mechanism involved in amino acid metabolism in an osmotic stress response, including the producing of γ-aminobutyric acid in C. sakazakii is still uncertain. This is the first report to determine the potential desiccation resistant factors of C. sakazakii at the proteomic levels.
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Transcriptome analysis of Cronobacter sakazakii ATCC BAA-894 after interaction with human intestinal epithelial cell line HCT-8. Appl Microbiol Biotechnol 2016; 100:311-22. [PMID: 26481623 DOI: 10.1007/s00253-015-7053-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 09/20/2015] [Accepted: 09/30/2015] [Indexed: 10/22/2022]
Abstract
Cronobacter spp. are opportunistic pathogens that are responsible for infections including severe meningitis, septicemia, and necrotizing enterocolitis in neonates and infants. To date, questions still remain regarding the mechanisms of pathogenicity and virulence determinants for each bacterial strain. In this study, we established an in vitro model for Cronobacter sakazakii ATCC BAA-894 infection of HCT-8 human colorectal epithelial cells. The transcriptome profile of C. sakazakii ATCC BAA-894 after interaction with HCT-8 cells was determined using high-throughput whole-transcriptome sequencing (RNA sequencing (RNA-seq)). Gene expression profiles indicated that 139 genes were upregulated and 72 genes were downregulated in the adherent C. sakazakii ATCC BAA-894 strain on HCT-8 cells compared to the cultured bacteria in the cell-free medium. Expressions of some flagella genes and virulence factors involved in adherence were upregulated. High osmolarity and osmotic stress-associated genes were highly upregulated, as well as genes responsible for the synthesis of lipopolysaccharides and outer membrane proteins, iron acquisition systems, and glycerol and glycerophospholipid metabolism. In sum, our study provides further insight into the mechanisms underlying C. sakazakii pathogenesis in the human gastrointestinal tract.
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9
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Du XJ, Han R, Li P, Wang S. Comparative proteomic analysis of Cronobacter sakazakii isolates with different virulences. J Proteomics 2015; 128:344-51. [PMID: 26327241 DOI: 10.1016/j.jprot.2015.08.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 07/24/2015] [Accepted: 08/21/2015] [Indexed: 10/23/2022]
Abstract
UNLABELLED Cronobacter is a genus of widespread, opportunistic, foodborne pathogens that can result in serious illnesses in at-risk infants because of their immature immunity and high dependence on powdered formula, which is one of the foods most often contaminated by this pathogen. However, limited information is available regarding the pathogenesis and the specific virulence factors of this species. In this study, the virulences of 42 Cronobacter sakazakii isolates were analyzed by infecting neonatal SD rats. A comparison of the typing patterns of the isolates enabled groups with close relationships but that exhibited distinct pathogenesis to be identified. Among these groups, 2 strains belonging to the same group but showing distinct virulences were selected, and 2-DE was applied to identify differentially expressed proteins, focusing on virulence-related proteins. A total of 111 protein spots were identified using matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF/TOF-MS), and 89 were successfully identified. Further analysis suggested that at least 11 of these proteins may be involved in the pathogenesis of this pathogen. Real-time PCR was carried out to further confirm the differential expression pattern of the genes, and the results indicated that the mRNA expression levels were consistent with the protein expression levels. BIOLOGICAL SIGNIFICANCE The virulence factors and pathogenesis of Cronobacter are largely unknown. In combination with animal toxicological experiments and subtyping results of C. sakazakii, comparative proteomics analysis was performed to comprehensively evaluate the differentially expressed proteins of two isolates that exhibited distinct virulence but were closely related. These procedures made it possible to identify the virulence-related of factors of Cronobacter. Among the 89 total identified proteins, at least 11 show virulence-related potential. This work provides comprehensive candidates for the further investigation of the pathogenesis of Cronobacter.
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Affiliation(s)
- Xin-jun Du
- Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Ran Han
- Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Ping Li
- Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Shuo Wang
- Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China.
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Carvalhais V, Cerveira F, Vilanova M, Cerca N, Vitorino R. An immunoproteomic approach for characterization of dormancy within Staphylococcus epidermidis biofilms. Mol Immunol 2015; 65:429-35. [PMID: 25749707 DOI: 10.1016/j.molimm.2015.02.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 02/19/2015] [Indexed: 01/02/2023]
Abstract
Virulence of Staphylococcus epidermidis is mainly attributed to surface colonization and biofilm formation in indwelling medical devices. Physiological heterogeneity of biofilms may influence host immune response and sensitivity to antibiotics. Dormant cells, among others, contribute to biofilm heterogeneity. The aim of this study was to identify immunogenic proteins of S. epidermidis biofilms associated with dormancy mechanism, by using two-dimensional electrophoresis (2-DE) immunoblotting and mass spectrometry (MS). A total of 19 bacterial proteins, recognized by human serum samples, were identified. These proteins were mainly involved in small molecule metabolic biological processes. Catalytic activity and ion binding were the most representative molecular functions. CodY and GpmA proteins were more reactive to sera when biofilm dormancy was induced, while FtnA and ClpP were more reactive when dormancy was prevented. This is the first work that identifies differences in immunoreactive proteins within bacterial biofilms with induced or prevented dormancy. Considering the importance of dormancy within biofilms, further evaluation of these proteins can provide insights into the mechanisms related to dormancy and help to improve current understanding on how dormancy affects the host immune response.
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Affiliation(s)
- Virginia Carvalhais
- QOPNA, Mass Spectrometry Center, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; CEB - Centre of Biological Engineering, LIBRO - Laboratory of Research in Biofilms Rosário Oliveira, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Frederico Cerveira
- Anatomia Patológica, Centro Hospitalar Baixo-Vouga, Avenida Artur Ravara, 3814-501 Aveiro, Portugal
| | - Manuel Vilanova
- IBMC - Instituto de Biologia Molecular e Celular, Rua do Campo Alegre 83, Porto, Portugal; ICBAS - Instituto de Ciências Biomédicas Abel Salazar, University of Porto, Rua de Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Nuno Cerca
- CEB - Centre of Biological Engineering, LIBRO - Laboratory of Research in Biofilms Rosário Oliveira, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Rui Vitorino
- QOPNA, Mass Spectrometry Center, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; iBiMED, Institute for Biomedical Research, University of Aveiro, Aveiro, Portugal.
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Kong D, Liu L, Xing C, Kuang H, Xu C. Sensitive and highly specific detection ofCronobacter sakazakiibased on monoclonal sandwich ELISA. FOOD AGR IMMUNOL 2015. [DOI: 10.1080/09540105.2014.998634] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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