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Yang D, Wang W, Zhao L, Rao L, Liao X. Resuscitation of viable but nonculturable bacteria promoted by ATP-mediated NAD + synthesis. J Adv Res 2024; 60:27-39. [PMID: 37541583 PMCID: PMC11156606 DOI: 10.1016/j.jare.2023.08.002] [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: 04/20/2023] [Revised: 07/04/2023] [Accepted: 08/02/2023] [Indexed: 08/06/2023] Open
Abstract
INTRODUCTION Entry into the viable but nonculturable (VBNC) state is a survival strategy adopted by bacteria to survive harsh environment. Although VBNC cells still have metabolic activity, they lose the ability to form colonies on nonselective culture media. Thus, conventional bacterial detection methods, such as plate counting, are unable to detect the presence of VBNC cells. When the environmental conditions are appropriate, VBNC cells can initiate resuscitation, posing a great risk to the safety of public health. The study of the VBNC resuscitation mechanism could provide new insights into the prevention and control of VBNC resuscitation. OBJECTIVES Uncovering the molecular mechanism of VBNC cell resuscitation by investigating the role of O-antigen ligase (RfaL) in inhibiting the resuscitation of Escherichia coli O157:H7 in the VBNC state. METHODS RfaL was screened and verified as a resuscitation inhibitor of VBNC Escherichia coli O157:H7 by detecting resuscitation curve and time-lapse microscopy. The mechanism of RfaL impacts VBNC E. coli resuscitation was investigated by detecting the single cell ATP content, metabolomic changes, NAD(H) content and new protein biosynthesis of WT and ΔrfaL at different stage of resuscitation. RESULTS Mutation of rfaL, which encoded an O-antigen ligase, markedly shortened the resuscitating lag phase. Further studies indicated that ΔrfaL VBNC cells contained higher ATP levels, and ATP consumption during the resuscitating lag phase was highly correlated with resuscitation efficiency. Metabolomic analysis revealed that ATP was utilized to activate the Handler and salvage pathways to synthesize NAD+, balancing redox reactions to recover cell activity and promote cell resuscitation. CONCLUSION Our findings revealed a strategy employed by VBNC cells for revival, that is, using residual ATP to primarily recover metabolic activity, driving cells to exit dormancy. The synthesis pathway of lipopolysaccharide (LPS) in rfaL null mutant was inhibited and could supply more ATP to synthesis NAD+ and promote resuscitation.
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Affiliation(s)
- Dong Yang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; National Engineering Research Center for Fruit & Vegetable Processing, Beijing, China; Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-thermal Processing, Beijing, China
| | - Wenxin Wang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; National Engineering Research Center for Fruit & Vegetable Processing, Beijing, China; Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-thermal Processing, Beijing, China
| | - Liang Zhao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; National Engineering Research Center for Fruit & Vegetable Processing, Beijing, China; Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-thermal Processing, Beijing, China
| | - Lei Rao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; National Engineering Research Center for Fruit & Vegetable Processing, Beijing, China; Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-thermal Processing, Beijing, China.
| | - Xiaojun Liao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; National Engineering Research Center for Fruit & Vegetable Processing, Beijing, China; Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-thermal Processing, Beijing, China.
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Ragunathan PT, Ng Kwan Lim E, Ma X, Massé E, Vanderpool CK. Mechanisms of Regulation of Cryptic Prophage-Encoded Gene Products in Escherichia coli. J Bacteriol 2023; 205:e0012923. [PMID: 37439671 PMCID: PMC10448788 DOI: 10.1128/jb.00129-23] [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: 04/10/2023] [Accepted: 06/12/2023] [Indexed: 07/14/2023] Open
Abstract
The dicBF operon of Qin cryptic prophage in Escherichia coli K-12 encodes the small RNA (sRNA) DicF and small protein DicB, which regulate host cell division and are toxic when overexpressed. While new functions of DicB and DicF have been identified in recent years, the mechanisms controlling the expression of the dicBF operon have remained unclear. Transcription from dicBp, the major promoter of the dicBF operon, is repressed by DicA. In this study, we discovered that transcription of the dicBF operon and processing of the polycistronic mRNA is regulated by multiple mechanisms. DicF sRNA accumulates during stationary phase and is processed from the polycistronic dicBF mRNA by the action of both RNase III and RNase E. DicA-mediated transcriptional repression of dicBp can be relieved by an antirepressor protein, Rem, encoded on the Qin prophage. Ectopic production of Rem results in cell filamentation due to strong induction of the dicBF operon, and filamentation is mediated by DicF and DicB. Spontaneous derepression of dicBp occurs in a subpopulation of cells independent of the antirepressor. This phenomenon is reminiscent of the bistable switch of λ phage with DicA and DicC performing functions similar to those of CI and Cro, respectively. Additional experiments demonstrate stress-dependent induction of the dicBF operon. Collectively, our results illustrate that toxic genes carried on cryptic prophages are subject to layered mechanisms of control, some that are derived from the ancestral phage and some that are likely later adaptations. IMPORTANCE Cryptic or defective prophages have lost genes necessary to excise from the bacterial chromosome and produce phage progeny. In recent years, studies have found that cryptic prophage gene products influence diverse aspects of bacterial host cell physiology. However, to obtain a complete understanding of the relationship between cryptic prophages and the host bacterium, identification of the environmental, host, or prophage-encoded factors that induce the expression of cryptic prophage genes is crucial. In this study, we examined the regulation of a cryptic prophage operon in Escherichia coli encoding a small RNA and a small protein that are involved in inhibiting bacterial cell division, altering host metabolism, and protecting the host bacterium from phage infections.
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Affiliation(s)
- Preethi T. Ragunathan
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
| | - Evelyne Ng Kwan Lim
- Department of Biochemistry and Functional Genomics, University of Sherbrooke, Sherbrooke, Québec, Canada
| | - Xiangqian Ma
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
| | - Eric Massé
- Department of Biochemistry and Functional Genomics, University of Sherbrooke, Sherbrooke, Québec, Canada
| | - Carin K. Vanderpool
- Department of Microbiology, University of Illinois Urbana-Champaign, Urbana, Illinois, USA
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Cheng S, Su R, Song L, Bai X, Yang H, Li Z, Li Z, Zhan X, Xia X, Lü X, Shi C. Citral and trans-cinnamaldehyde, two plant-derived antimicrobial agents can induce Staphylococcus aureus into VBNC state with different characteristics. Food Microbiol 2023; 112:104241. [PMID: 36906323 DOI: 10.1016/j.fm.2023.104241] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 02/10/2023] [Accepted: 02/15/2023] [Indexed: 02/19/2023]
Abstract
Viable but nonculturable (VBNC) state bacteria are difficult to detect in the food industry due to their nonculturable nature and their recovery characteristics pose a potential threat to human health. The results of this study indicated that S. aureus was found to enter the VBNC state completely after induced by citral (1 and 2 mg/mL) for 2 h, and after induced by trans-cinnamaldehyde (0.5 and 1 mg/mL) for 1 h and 3 h, respectively. Except for VBNC state cells induced by 2 mg/mL citral, the VBNC state cells induced by the other three conditions (1 mg/mL citral, 0.5 and 1 mg/mL trans-cinnamaldehyde) were able to be resuscitated in TSB media. In the VBNC state cells induced by citral and trans-cinnamaldehyde, the ATP concentration was reduced, the hemolysin-producing ability was significantly decreased, but the intracellular ROS level was elevated. The results of heat and simulated gastric fluid experiments showed different environment resistance on VBNC state cells induced by citral and trans-cinnamaldehyde. In addition, by observing the VBNC state cells showed that irregular folds on the surface, increased electron density inside and vacuoles in the nuclear region. What's more, S. aureus was found to enter the VBNC state completely after induced by meat-based broth containing citral (1 and 2 mg/mL) for 7 h and 5 h, after induced by meat-based broth containing trans-cinnamaldehyde (0.5 and 1 mg/mL) for 8 h and 7 h. In summary, citral and trans-cinnamaldehyde can induce S. aureus into VBNC state and food industry needs to comprehensively evaluate the antibacterial capacity of these two plant-derived antimicrobial agents.
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Affiliation(s)
- Shuai Cheng
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Ruiying Su
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Luyi Song
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xiangyang Bai
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Hui Yang
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Zhuo Li
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Zhenye Li
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xiangjun Zhan
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xiaodong Xia
- School of Food Science and Technology, National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian, 116304, China
| | - Xin Lü
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Chao Shi
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, China.
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Pan H, Yang D, Wang Y, Rao L, Liao X. Acid shock protein Asr induces protein aggregation to promote E. coli O157:H7 entering viable but non-culturable state under high pressure carbon dioxide stress. Food Microbiol 2023; 109:104136. [DOI: 10.1016/j.fm.2022.104136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 07/31/2022] [Accepted: 09/05/2022] [Indexed: 10/14/2022]
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Yang D, Li R, Dong P, Rao L, Wang Y, Liao X. Influence of pressurization rate and mode on cell damage of Escherichia coli and Staphyloccocus aureus by high hydrostatic pressure. Front Microbiol 2023; 14:1108194. [PMID: 36937272 PMCID: PMC10018152 DOI: 10.3389/fmicb.2023.1108194] [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: 11/25/2022] [Accepted: 02/13/2023] [Indexed: 03/06/2023] Open
Abstract
As a non-thermal technology, high hydrostatic pressure (HHP) has been widely investigated for inactivating microorganisms in food. Few studies have been presented on the pressurization/depressurization rate and mode of microbial inactivation. In this study, effect of pressurization rate and mode on Escherichia coli and Staphylococcus aureus cell damage during HHP treatment was investigated. The results showed that fast pressurization + linear mode (FL) treatment has the best bactericidal effect on E. coli and S. aureus, followed by fast pressurization + stepwise mode (FS) and slow pressurization + stepwise mode (SS) treatments. FL treatment caused more morphological damage to the cell wall, cell membrane, and cytoplasmic components compared with FS and SS treatment detected by SEM and TEM. Additionally, the damage to membrane permeability of them was also enhanced after FL treatment. Therefore, our results indicated that FL treatment could be applied to enhance the bactericidal effect of HHP on bacteria by increasing the damage to cell morphological structure and membrane integrity.
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Affiliation(s)
- Dong Yang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
- National Engineering Research Center for Fruit and Vegetable Processing, Beijing, China
- Key Lab of Fruit and Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing, China
- Beijing Key Laboratory for Food Non-Thermal Processing, Beijing, China
| | - Renjie Li
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
- National Engineering Research Center for Fruit and Vegetable Processing, Beijing, China
- Key Lab of Fruit and Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing, China
- Beijing Key Laboratory for Food Non-Thermal Processing, Beijing, China
| | - Peng Dong
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
- National Engineering Research Center for Fruit and Vegetable Processing, Beijing, China
- Key Lab of Fruit and Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing, China
- Beijing Key Laboratory for Food Non-Thermal Processing, Beijing, China
| | - Lei Rao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
- National Engineering Research Center for Fruit and Vegetable Processing, Beijing, China
- Key Lab of Fruit and Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing, China
- Beijing Key Laboratory for Food Non-Thermal Processing, Beijing, China
| | - Yongtao Wang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
- National Engineering Research Center for Fruit and Vegetable Processing, Beijing, China
- Key Lab of Fruit and Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing, China
- Beijing Key Laboratory for Food Non-Thermal Processing, Beijing, China
- *Correspondence: Yongtao Wang,
| | - Xiaojun Liao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
- National Engineering Research Center for Fruit and Vegetable Processing, Beijing, China
- Key Lab of Fruit and Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing, China
- Beijing Key Laboratory for Food Non-Thermal Processing, Beijing, China
- Xiaojun Liao,
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Wake Up! Resuscitation of Viable but Nonculturable Bacteria: Mechanism and Potential Application. Foods 2022; 12:foods12010082. [PMID: 36613298 PMCID: PMC9818539 DOI: 10.3390/foods12010082] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/12/2022] [Accepted: 12/16/2022] [Indexed: 12/29/2022] Open
Abstract
The viable but nonculturable (VBNC) state is a survival strategy for bacteria when encountered with unfavorable conditions. Under favorable environments such as nutrient supplementation, external stress elimination, or supplementation with resuscitation-promoting substances, bacteria will recover from the VBNC state, which is termed "resuscitation". The resuscitation phenomenon is necessary for proof of VBNC existence, which has been confirmed in different ways to exclude the possibility of culturable-cell regrowth. The resuscitation of VBNC cells has been widely studied for the purpose of risk control of recovered pathogenic or spoilage bacteria. From another aspect, the resuscitation of functional bacteria can also be considered a promising field to explore. To support this point, the resuscitation mechanisms were comprehensively reviewed, which could provide the theoretical foundations for the application of resuscitated VBNC cells. In addition, the proposed applications, as well as the prospects for further applications of resuscitated VBNC bacteria in the food industry are discussed in this review.
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Gagarinova A, Hosseinnia A, Rahmatbakhsh M, Istace Z, Phanse S, Moutaoufik MT, Zilocchi M, Zhang Q, Aoki H, Jessulat M, Kim S, Aly KA, Babu M. Auxotrophic and prototrophic conditional genetic networks reveal the rewiring of transcription factors in Escherichia coli. Nat Commun 2022; 13:4085. [PMID: 35835781 PMCID: PMC9283627 DOI: 10.1038/s41467-022-31819-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 07/05/2022] [Indexed: 11/25/2022] Open
Abstract
Bacterial transcription factors (TFs) are widely studied in Escherichia coli. Yet it remains unclear how individual genes in the underlying pathways of TF machinery operate together during environmental challenge. Here, we address this by applying an unbiased, quantitative synthetic genetic interaction (GI) approach to measure pairwise GIs among all TF genes in E. coli under auxotrophic (rich medium) and prototrophic (minimal medium) static growth conditions. The resulting static and differential GI networks reveal condition-dependent GIs, widespread changes among TF genes in metabolism, and new roles for uncharacterized TFs (yjdC, yneJ, ydiP) as regulators of cell division, putrescine utilization pathway, and cold shock adaptation. Pan-bacterial conservation suggests TF genes with GIs are co-conserved in evolution. Together, our results illuminate the global organization of E. coli TFs, and remodeling of genetic backup systems for TFs under environmental change, which is essential for controlling the bacterial transcriptional regulatory circuits. The bacterium E. coli has around 300 transcriptional factors, but the functions of many of them, and the interactions between their respective regulatory networks, are unclear. Here, the authors study genetic interactions among all transcription factor genes in E. coli, revealing condition-dependent interactions and roles for uncharacterized transcription factors.
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Affiliation(s)
- Alla Gagarinova
- Department of Biochemistry, University of Regina, Regina, SK, Canada
| | - Ali Hosseinnia
- Department of Biochemistry, University of Regina, Regina, SK, Canada
| | | | - Zoe Istace
- Department of Biochemistry, University of Regina, Regina, SK, Canada
| | - Sadhna Phanse
- Department of Biochemistry, University of Regina, Regina, SK, Canada
| | | | - Mara Zilocchi
- Department of Biochemistry, University of Regina, Regina, SK, Canada
| | - Qingzhou Zhang
- Department of Biochemistry, University of Regina, Regina, SK, Canada
| | - Hiroyuki Aoki
- Department of Biochemistry, University of Regina, Regina, SK, Canada
| | - Matthew Jessulat
- Department of Biochemistry, University of Regina, Regina, SK, Canada
| | - Sunyoung Kim
- Department of Biochemistry, University of Regina, Regina, SK, Canada
| | - Khaled A Aly
- Department of Biochemistry, University of Regina, Regina, SK, Canada
| | - Mohan Babu
- Department of Biochemistry, University of Regina, Regina, SK, Canada.
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Yang D, Wang Y, Zhao L, Rao L, Liao X. Extracellular pH decline introduced by high pressure carbon dioxide is a main factor inducing bacteria to enter viable but non-culturable state. Food Res Int 2022; 151:110895. [PMID: 34980417 DOI: 10.1016/j.foodres.2021.110895] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 12/07/2021] [Accepted: 12/10/2021] [Indexed: 11/04/2022]
Abstract
High pressure carbon dioxide (HPCD) has been used in food processing as a non-thermal pasteurization technology. However, the potential of HPCD to induce viable but non-culturable (VBNC) cells limits its application. The objective of this study was to explore the roles of extracellular pH of 3 (pHex3) and high pressure (HP) of HPCD during VBNC induction and the underlying molecular mechanism. By using the model organism Escherichia coli O157:H7, we found that the combined effects of pHex3 and HP could mimic the effect of HPCD for VBNC induction. Further investigation of the individual effect of pHex3 and HP on VBNC induction revealed that pHex3 could induce a higher proportion of VBNC cells with a slower induction rate compared with HPCD, whereas HP was unable to induce VBNC formation. Notably, the cells treated by pHex3 and HPCD had similar morphological changes, and VBNC cells induced by pHex3 and HPCD had similar stress resistance characteristics. These results strongly indicated that pHex3 introduced by HPCD was a main factor for VBNC induction. Additionally, we found that HP played the role in accelerating VBNC formation in the process of HPCD treatment. Transcriptomic analysis revealed 85, 263 and 529 differentially expressed genes (DEGs) for HP-, pHex3- and HPCD-treated cells compared with untreated ones. 59 DEGs shared by pHex3 and HPCD treatment might be responsible for VBNC induction, and they were mainly involved in cellular transport and localization.
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Affiliation(s)
- Dong Yang
- College of Food Science and Nutritional Engineering, China Agricultural University, National Engineering Research Center for Fruit & Vegetable Processing, Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-thermal Processing, Beijing 100083, China
| | - Yongtao Wang
- College of Food Science and Nutritional Engineering, China Agricultural University, National Engineering Research Center for Fruit & Vegetable Processing, Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-thermal Processing, Beijing 100083, China
| | - Liang Zhao
- College of Food Science and Nutritional Engineering, China Agricultural University, National Engineering Research Center for Fruit & Vegetable Processing, Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-thermal Processing, Beijing 100083, China
| | - Lei Rao
- College of Food Science and Nutritional Engineering, China Agricultural University, National Engineering Research Center for Fruit & Vegetable Processing, Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-thermal Processing, Beijing 100083, China.
| | - Xiaojun Liao
- College of Food Science and Nutritional Engineering, China Agricultural University, National Engineering Research Center for Fruit & Vegetable Processing, Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-thermal Processing, Beijing 100083, China.
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Gao R, Liao X, Zhao X, Liu D, Ding T. The diagnostic tools for viable but nonculturable pathogens in the food industry: Current status and future prospects. Compr Rev Food Sci Food Saf 2021; 20:2146-2175. [PMID: 33484068 DOI: 10.1111/1541-4337.12695] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/21/2020] [Accepted: 12/28/2020] [Indexed: 12/21/2022]
Abstract
Viable but nonculturable (VBNC) microorganisms have been recognized as pathogenic contaminants in foods and environments. The failure of VBNC cells to form the visible colonies hinders the ability to use conventional media for their detection. Efficient and rapid detection of pathogens in the VBNC state is a prerequisite to ensure the food safety and public health. Despite their nonculturability, VBNC cells have distinct characteristics, such as morphology, metabolism, chemical composition, and gene and protein expression, that have been used as the basis for the development of abundant diagnostic tools. This review covers the current status and advances in various approaches for examining microorganisms in the VBNC state, including but not limited to the methodological aspects, advantages, and drawbacks of each technique. Existing methods, such as direct viable count, SYTO/PI dual staining, and propidium monoazide quantitative polymerase chain reaction (PCR), as well as some techniques with potential to be applied in the future, such as digital PCR, enhanced-surface Raman spectroscopy, and impedance-based techniques, are summarized in depth. Finally, future prospects for the one-step detection of VBNC bacteria are proposed and discussed. We believe that this review can provide more optional methods for researchers and promote the development of rapid, accurate detecting methods, and for inspectors, the diagnostic tools can provide data to undertake risk analysis of VBNC cells.
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Affiliation(s)
- Rui Gao
- Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xinyu Liao
- Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xihong Zhao
- Research Center for Environmental Ecology and Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Donghong Liu
- Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang, China
| | - Tian Ding
- Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang, China
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Characterization of DicB Inhibitory Activity in Cell Division Under Stress Conditions. Chem Res Chin Univ 2020. [DOI: 10.1007/s40242-020-0248-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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