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Hanes R, Liu Y, Huang Z. Druggability Analysis of Protein Targets for Drug Discovery to Combat Listeria monocytogenes. Microorganisms 2024; 12:1073. [PMID: 38930455 PMCID: PMC11205737 DOI: 10.3390/microorganisms12061073] [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: 04/15/2024] [Revised: 05/19/2024] [Accepted: 05/21/2024] [Indexed: 06/28/2024] Open
Abstract
Extensive research has been conducted to identify key proteins governing stress responses, virulence, and antimicrobial resistance, as well as to elucidate their interactions within Listeria monocytogenes. While these proteins hold promise as potential targets for novel strategies to control L. monocytogenes, given their critical roles in regulating the pathogen's metabolism, additional analysis is needed to further assess their druggability-the chance of being effectively bound by small-molecule inhibitors. In this work, 535 binding pockets of 46 protein targets for known drugs (mainly antimicrobials) were first analyzed to extract 13 structural features (e.g., hydrophobicity) in a ligand-protein docking platform called Molsoft ICM Pro. The extracted features were used as inputs to develop a logistic regression model to assess the druggability of protein binding pockets, with a value of one if ligands can bind to the protein pocket. The developed druggability model was then used to evaluate 23 key proteins from L. monocytogenes that have been identified in the literature. The following proteins are predicted to be high-potential druggable targets: GroEL, FliH/FliI complex, FliG, FlhB, FlgL, FlgK, InlA, MogR, and PrfA. These findings serve as an initial point for future research to identify specific compounds that can inhibit druggable target proteins and to design experimental work to confirm their effectiveness as drug targets.
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Affiliation(s)
- Robert Hanes
- Department of Chemical and Biological Engineering, Villanova University, Villanova, PA 19085, USA;
| | - Yanhong Liu
- Eastern Regional Research Center, U.S. Department of Agriculture, Wyndmoor, PA 19038, USA
| | - Zuyi Huang
- Department of Chemical and Biological Engineering, Villanova University, Villanova, PA 19085, USA;
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2
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Alejandro-Navarreto X, Freitag NE. Revisiting old friends: updates on the role of two-component signaling systems in Listeria monocytogenes survival and pathogenesis. Infect Immun 2024; 92:e0034523. [PMID: 38591895 PMCID: PMC11003226 DOI: 10.1128/iai.00345-23] [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] [Indexed: 04/10/2024] Open
Abstract
Listeria monocytogenes is well recognized for both its broad resistance to stress conditions and its ability to transition from a soil bacterium to an intracellular pathogen of mammalian hosts. The bacterium's impressive ability to adapt to changing environments and conditions requires the rapid sensing of environmental cues and the coordinated response of gene products that enable bacterial growth and survival. Two-component signaling systems (TCSs) have been long recognized for their ability to detect environmental stimuli and transmit those signals into transcriptional responses; however, often the precise nature of the stimulus triggering TCS responses can be challenging to define. L. monocytogenes has up to 16 TCSs that have been recognized based on homology and included in this list are several whose functions remain poorly described. This review highlights the current understanding of the breadth and scope of L. monocytogenes TCS as relates to stress resistance and pathogenesis. Precise signals still often remain elusive, but the gene networks associated with TCSs are providing clues into possible functions.
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Affiliation(s)
| | - Nancy E. Freitag
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, Illinois, USA
- Department of Pharmaceutical Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
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Pan X, Shen J, Hong Y, Wu Y, Guo D, Zhao L, Bu X, Ben L, Wang X. Comparative Analysis of Growth, Survival, and Virulence Characteristics of Listeria monocytogenes Isolated from Imported Meat. Microorganisms 2024; 12:345. [PMID: 38399749 PMCID: PMC10891628 DOI: 10.3390/microorganisms12020345] [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: 01/08/2024] [Revised: 01/28/2024] [Accepted: 02/01/2024] [Indexed: 02/25/2024] Open
Abstract
Listeria monocytogenes is an important foodborne pathogen with worldwide prevalence. Understanding the variability in the potential pathogenicity among strains of different subtypes is crucial for risk assessment. In this study, the growth, survival, and virulence characteristics of 16 L. monocytogenes strains isolated from imported meat in China (2018-2020) were investigated. The maximum specific growth rate (μmax) and lag phase (λ) were evaluated using the time-to-detection (TTD) method and the Baranyi model at different temperatures (25, 30, and 37 °C). Survival characteristics were determined by D-values and population reduction after exposure to heat (60, 62.5, and 65 °C) and acid (HCl, pH = 2.5, 3.5, and 4.5). The potential virulence was evaluated via adhesion and invasion to Caco-2 cells, motility, and lethality to Galleria mellonella. The potential pathogenicity was compared among strains of different lineages and subtypes. The results indicate that the lineage I strains exhibited a higher growth rate than the lineage II strains at three growth temperatures, particularly serotype 4b within lineage I. At all temperatures tested, serotypes 1/2a and 1/2b consistently demonstrated higher heat resistance than the other subtypes. No significant differences in the log reduction were observed between the lineage I and lineage II strains at pH 2.5, 3.5, and 4.5. However, the serotype 1/2c strains exhibited significantly low acid resistance at pH 2.5. In terms of virulence, the lineage I strains outperformed the lineage II strains. The invasion rate to Caco-2 cells and lethality to G. mellonella exhibited by the serotype 4b strains were higher than those observed in the other serotypes. This study provides meaningful insights into the growth, survival, and virulence of L. monocytogenes, offering valuable information for understanding the correlation between the pathogenicity and subtypes of L. monocytogenes.
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Affiliation(s)
- Xinye Pan
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (X.P.); (Y.H.); (X.B.); (L.B.)
| | - Jinling Shen
- Technology Center for Animal Plant and Food Inspection and Quarantine of Shanghai Customs, Shanghai 200135, China; (J.S.); (D.G.); (L.Z.)
| | - Yi Hong
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (X.P.); (Y.H.); (X.B.); (L.B.)
| | - Yufan Wu
- Centre of Analysis and Test, School of Chemistry & Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China;
| | - Dehua Guo
- Technology Center for Animal Plant and Food Inspection and Quarantine of Shanghai Customs, Shanghai 200135, China; (J.S.); (D.G.); (L.Z.)
| | - Lina Zhao
- Technology Center for Animal Plant and Food Inspection and Quarantine of Shanghai Customs, Shanghai 200135, China; (J.S.); (D.G.); (L.Z.)
| | - Xiangfeng Bu
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (X.P.); (Y.H.); (X.B.); (L.B.)
| | - Leijie Ben
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (X.P.); (Y.H.); (X.B.); (L.B.)
| | - Xiang Wang
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (X.P.); (Y.H.); (X.B.); (L.B.)
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Kumari K, Sharma PK, Singh RP. Unravelling the transcriptome response of Enterobacter sp. S-33 under varying temperature. Arch Microbiol 2024; 206:81. [PMID: 38294553 DOI: 10.1007/s00203-023-03792-6] [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: 11/22/2023] [Revised: 11/22/2023] [Accepted: 12/11/2023] [Indexed: 02/01/2024]
Abstract
Enterobacter genus includes the bacteria occupying every aspect of environment, however, their adaptability at varying temperature is not clear. In the present study, we analyzed the transcriptome response of Enterobacter sp. S-33 and their functional genes under various temperatures (30-45 ℃) that were expressed and accumulated in cells under temperature-stress. During a temperature shift from 37 to 45 ℃, 165 genes showed differential expression including 112 up-regulated and 53 down-regulated. In particular, heat-shock genes such as CspA, 16 kDa heat shock protein A/B and transcriptional regulators such as LysR, TetR, and LuxR were differentially expressed, indicating the role of complex molecular mechanism of Enterobacter adapting to temperature stress. Similarly, genes associated to signal transduction, ABC transporters, iron homeostasis, and quorum sensing were also induced. The Gene ontology enrichment analysis of differentially expressed genes (DEGs) were categorized into "transmembrane transport", "tRNA binding", "hydrogen sulfide biosynthetic process" and "sulfate assimilation" terms. In addition, Kyoto Encyclopedia of Genes and Genomes pathways showed that ABC transporter as well as quorum sensing pathways were significantly enriched. Overall, current study has contributed to explore the adaptive molecular mechanisms of Enterobacter spp. upon temperature change, which further opens new avenues for future in-depth functional studies.
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Affiliation(s)
- Kiran Kumari
- Department of Bioengineering and Biotechnology, Birla Institute of Technology, Mesra, Ranchi, Jharkhand, 835215, India
| | - Parva Kumar Sharma
- Department of Plant Sciences and Landscape Architecture, University of Maryland, College Park, MD, 20742, USA
| | - Rajnish Prakash Singh
- Department of Biotechnology, Jaypee Institute of Information Technology, Noida, India.
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Wang W, Liu JS, Zhou JW, Jia AQ. Synergistic effect of kanamycin and amikacin with setomimycin on biofilm formation inhibition of Listeria monocytogenes. Microb Pathog 2023; 185:106447. [PMID: 37972742 DOI: 10.1016/j.micpath.2023.106447] [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: 07/30/2023] [Revised: 10/12/2023] [Accepted: 11/08/2023] [Indexed: 11/19/2023]
Abstract
Listeria monocytogenes, a foodborne pathogen that causes listeriosis with high fatality rate, exhibits multidrug resistance (MDR) known to be progressively increasing. Alternative antibacterial strategies are in high demand for treating this well-known pathogen. Anti-biofilm and anti-virulence strategies are being explored as novel approaches to treat bacterial infections. In this study, one rare antibacterial named setomimycin was isolated from Streptomyces cyaneochromogenes, which showed potent antibacterial activity against L. monocytogenes. Next, the inhibition of biofilm formation and listeriolysin O (LLO) production against L. monocytogenes were investigated at sub-minimal inhibitory concentrations (sub-MICs) of setomimycin alone or combined with kanamycin and amikacin. Crystal violet staining confirmed that setomimycin combining with kanamycin or amikacin could dramatically reduce biofilm formation against L. monocytogenes at sub-MICs, which was further evaluated by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). In the meantime, sub-MICs of setomimycin could significantly suppress the secretion of LLO. Furthermore, the transcription of genes associated with biofilms and main virulence factors, such as LLO, flagellum, and metalloprotease, were suppressed by setomimycin at sub-MICs. Hence, the study provided a deep insight into setomimycin as an alternative antibacterial agent against L. monocytogenes.
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Affiliation(s)
- Wei Wang
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Pharmaceutical Sciences, Hainan University, Haikou, 570228, China; Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou, 570311, China
| | - Jun-Sheng Liu
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Pharmaceutical Sciences, Hainan University, Haikou, 570228, China
| | - Jin-Wei Zhou
- School of Food and Biological Engineering, Xuzhou University of Technology, Xuzhou, 221018, China
| | - Ai-Qun Jia
- Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou, 570311, China.
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Böer T, Bengelsdorf FR, Bömeke M, Daniel R, Poehlein A. Genome-based metabolic and phylogenomic analysis of three Terrisporobacter species. PLoS One 2023; 18:e0290128. [PMID: 37816002 PMCID: PMC10564238 DOI: 10.1371/journal.pone.0290128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 09/27/2023] [Indexed: 10/12/2023] Open
Abstract
Acetogenic bacteria are of high interest for biotechnological applications as industrial platform organisms, however, acetogenic strains from the genus Terrisporobacter have hitherto been neglected. To date, three published type strains of the genus Terrisporobacter are only covered by draft genome sequences, and the genes and pathway responsible for acetogenesis have not been analyzed. Here, we report complete genome sequences of the bacterial type strains Terrisporobacter petrolearius JCM 19845T, Terrisporobacter mayombei DSM 6539T and Terrisporobacter glycolicus DSM 1288T. Functional annotation, KEGG pathway module reconstructions and screening for virulence factors were performed. Various species-specific vitamin, cofactor and amino acid auxotrophies were identified and a model for acetogenesis of Terrisporobacter was constructed. The complete genomes harbored a gene cluster for the reductive proline-dependent branch of the Stickland reaction located on an approximately 21 kb plasmid, which is exclusively found in the Terrisporobacter genus. Phylogenomic analysis of available Terrisporobacter genomes suggested a reclassification of most isolates as T. glycolicus into T. petrolearius.
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Affiliation(s)
- Tim Böer
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Göttingen, Germany
| | - Frank R. Bengelsdorf
- Institute for Molecular Biology and Biotechnology of Prokaryotes, University Ulm, Ulm, Germany
| | - Mechthild Bömeke
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Göttingen, Germany
| | - Rolf Daniel
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Göttingen, Germany
| | - Anja Poehlein
- Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Göttingen, Germany
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Abdulkadieva MM, Sysolyatina EV, Vasilieva EV, Litvinenko VV, Kalinin EV, Zhukhovitsky VG, Shevlyagina NV, Andreevskaya SG, Stanishevskyi YM, Vasiliev MM, Petrov OF, Ermolaeva SA. Motility provides specific adhesion patterns and improves Listeria monocytogenes invasion into human HEp-2 cells. PLoS One 2023; 18:e0290842. [PMID: 37651463 PMCID: PMC10470941 DOI: 10.1371/journal.pone.0290842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 08/17/2023] [Indexed: 09/02/2023] Open
Abstract
Listeria monocytogenes is motile at 22°C and non-motile at 37°C. In contrast, expression of L. monocytogenes virulence factors is low at 22°C and up-regulated at 37°C. Here, we studied a character of L. monocytogenes near surface swimming (NSS) motility and its effects on adhesion patterns and invasion into epithelial cells. L. monocytogenes and its saprophytic counterpart L. innocua both grown at 22°C showed similar NSS characteristics including individual velocities, trajectory lengths, residence times, and an asymmetric distribution of velocity directions. Similar NSS patterns correlated with similar adhesion patterns. Motile bacteria, including both pathogenic and saprophytic species, showed a preference for adhering to the periphery of epithelial HEp-2 cells. In contrast, non-motile bacteria were evenly distributed across the cell surface, including areas over the nucleus. However, the uneven distribution of motile bacteria did not enhance the invasion into HEp-2 cells unless virulence factor production was up-regulated by the transient shift of the culture to 37°C. Motile L. monocytogenes grown overnight at 22°C and then shifted to 37°C for 2 h expressed invasion factors at the same level and invaded human cells up to five times more efficiently comparatively with non-motile bacteria grown overnight at 37°C. Taken together, obtained results demonstrated that (i) NSS motility and correspondent peripheral location over the cell surface did not depend on L. monocytogenes virulence traits; (ii) motility improved L. monocytogenes invasion into human HEp-2 cells within a few hours after the transition from the ambient temperature to the human body temperature.
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Affiliation(s)
- Mariam M. Abdulkadieva
- Department of Infections with Natural Foci, Gamaleya National Research Centre of Epidemiology and Microbiology, Moscow, Russia
- Department of Dusty Plasmas, Joint Institute of High Temperatures RAS, Moscow, Russia
- Institute of Biochemical Technology and Nanotechnology, People’s Friendship University RUDN, Moscow, Russia
| | - Elena V. Sysolyatina
- Department of Infections with Natural Foci, Gamaleya National Research Centre of Epidemiology and Microbiology, Moscow, Russia
| | - Elena V. Vasilieva
- Department of Infections with Natural Foci, Gamaleya National Research Centre of Epidemiology and Microbiology, Moscow, Russia
- Department of Dusty Plasmas, Joint Institute of High Temperatures RAS, Moscow, Russia
| | - Veronika V. Litvinenko
- Department of Infections with Natural Foci, Gamaleya National Research Centre of Epidemiology and Microbiology, Moscow, Russia
- Department of Dusty Plasmas, Joint Institute of High Temperatures RAS, Moscow, Russia
| | - Egor V. Kalinin
- Department of Infections with Natural Foci, Gamaleya National Research Centre of Epidemiology and Microbiology, Moscow, Russia
- Institute of Biochemical Technology and Nanotechnology, People’s Friendship University RUDN, Moscow, Russia
| | - Vladimir G. Zhukhovitsky
- Department of Bacterial Infections, Gamaleya National Research Centre of Epidemiology and Microbiology, Moscow, Russia
- Russian Medical Academy of Continuing Professional Education (RMANPO), Ministry of Public Health, Moscow, Russia
| | - Natalia V. Shevlyagina
- Department of Bacterial Infections, Gamaleya National Research Centre of Epidemiology and Microbiology, Moscow, Russia
| | - Svetlana G. Andreevskaya
- Department of Bacterial Infections, Gamaleya National Research Centre of Epidemiology and Microbiology, Moscow, Russia
| | - Yaroslav M. Stanishevskyi
- Institute of Biochemical Technology and Nanotechnology, People’s Friendship University RUDN, Moscow, Russia
| | - Mikhail M. Vasiliev
- Department of Dusty Plasmas, Joint Institute of High Temperatures RAS, Moscow, Russia
| | - Oleg F. Petrov
- Department of Dusty Plasmas, Joint Institute of High Temperatures RAS, Moscow, Russia
| | - Svetlana A. Ermolaeva
- Department of Infections with Natural Foci, Gamaleya National Research Centre of Epidemiology and Microbiology, Moscow, Russia
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Hanes R, Zhang F, Huang Z. Protein Interaction Network Analysis to Investigate Stress Response, Virulence, and Antibiotic Resistance Mechanisms in Listeria monocytogenes. Microorganisms 2023; 11:microorganisms11040930. [PMID: 37110353 PMCID: PMC10144942 DOI: 10.3390/microorganisms11040930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/29/2023] [Accepted: 03/31/2023] [Indexed: 04/05/2023] Open
Abstract
Listeria monocytogenes is a deadly and costly foodborne pathogen that has a high fatality rate in the elderly, pregnant women, and people with weakened immunity. It can survive under various stress conditions and is a significant concern for the food industry. In this work, a data analysis approach was developed with existing tools and databases and used to create individual and combined protein interaction networks to study stress response, virulence, and antimicrobial resistance and their interaction with L. monocytogenes. The networks were analyzed, and 28 key proteins were identified that may serve as potential targets for new strategies to combat L. monocytogenes. Five of the twenty-eight proteins (i.e., sigB, flaA, cheA, cheY, and lmo0693) represent the most promising targets because they are highly interconnected within the combined network. The results of this study provide a new set of targets for future work to identify new strategies to improve food preservation methods and treatments for L. monocytogenes.
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Affiliation(s)
- Robert Hanes
- Department of Chemical Engineering, Villanova University, Villanova, PA 19085, USA
| | - Fangyuan Zhang
- Department of Chemical Engineering, Villanova University, Villanova, PA 19085, USA
| | - Zuyi Huang
- Department of Chemical Engineering, Villanova University, Villanova, PA 19085, USA
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Pan-Genome Analysis of Campylobacter: Insights on the Genomic Diversity and Virulence Profile. Microbiol Spectr 2022; 10:e0102922. [PMID: 36069574 PMCID: PMC9602946 DOI: 10.1128/spectrum.01029-22] [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] [Indexed: 01/04/2023] Open
Abstract
The genus Campylobacter contains pathogens that cause bacterial gastroenteritis in humans and animals. Despite large-scale sequencing efforts to raise clinical awareness of Campylobacter, little is known about the diversity and functions of virulence factors. Here, we constructed the pan-genome of Campylobacter using 39 representative genomes, elucidating their genetic diversity, evolutionary characteristics, and virulence and resistance profiles. The Campylobacter pan-genome was open and showed extensive genome variability, with high levels of gene expansion and contraction as the organism evolved. These Campylobacter members had diverse virulence gene content, and six potential core virulence genes (porA, PEB4, cheY, htrB, Cj1135, and kpsF) have been identified. The conserved mechanisms for Campylobacter pathogenicity were related to adherence, motility, and immune modulation. We emphasized the relative importance of variable virulence genes. Many virulence genes have experienced expansion or contraction in specific lineages, which may be one of the factors causing differences in the content of virulence genes. Additionally, these Campylobacter genomes have a high prevalence of the cmeA and cmeC genes, which are linked to the CmeABC pump and contribute to multidrug resistance. The genomic variations, core and variable virulence factors, and resistance genes of Campylobacter characterized in this study would contribute to a better understanding of the virulence of Campylobacter and more effective use of candidates for drug development and prevention of Campylobacter infections. IMPORTANCE Pathogenic members of the genus Campylobacter are recognized as one of the major causative agents of human bacterial gastroenteritis. This study revealed the pan-genome of 39 Campylobacter species, provided the most updated reconstruction of the global virulence gene pool of 39 Campylobacter species, and identified species-related virulence differences. This study highlighted the basic conserved functionality and specificity of pathogenicity that are crucial to infection, which was critical for improving the diagnosis and prevention of Campylobacter infections.
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Wang Q, Wang P, Liu P, Ou J. Comparative Transcriptome Analysis Reveals Regulatory Factors Involved in Vibrio Parahaemolyticus Biofilm Formation. Front Cell Infect Microbiol 2022; 12:917131. [PMID: 35899046 PMCID: PMC9309355 DOI: 10.3389/fcimb.2022.917131] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Accepted: 06/10/2022] [Indexed: 11/13/2022] Open
Abstract
Vibrio parahaemolyticus biofilm poses a serious threat to food safety and human health. However, there is limited knowledge of transcriptional regulatory mechanism during the biofilm formation of this organism. Hence, the RNA sequencing technique was employed to compare the differences in transcriptome profiles between planktonic and biofilm state of V. parahaemolyticus ATCC33847 in this study. Collections of mRNA from planktonic and biofilm cells cultured at 25°C for 36 h were sequenced by studying their biological characteristics. The results showed that there were significant differences in the expression levels of 956 genes in biofilms compared with planktonic cells. These differences suggested that two-component regulatory system (TCS) and quorum sensing (QS) regulated V. parahaemolyticus biofilm formation by affecting important factors such as flagellar motility, Extracellular polymeric substance (EPS) secretion, tripartite ATP-independent (TRAP) transport system and ATP binding cassette (ABC) transport system. The present work in transcriptomics serves as a basis for future studies examining the complex network systems that regulate bacterial biofilm formation.
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Affiliation(s)
- Qiuyu Wang
- College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
| | - Pengfei Wang
- College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
| | - Pingping Liu
- College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
| | - Jie Ou
- College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
- Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture and Rural Affairs, Shanghai, China
- Shanghai Engineering Research Center of Aquatic-Product Processing and Preservation, Shanghai, China
- *Correspondence: Jie Ou,
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11
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Liu Y, Yoo BB, Hwang CA, Martinez MR, Datta AR, Fratamico PM. Involvement of a putative ATP-Binding Cassette (ABC) Involved in manganese transport in virulence of Listeria monocytogenes. PLoS One 2022; 17:e0268924. [PMID: 35617277 PMCID: PMC9135185 DOI: 10.1371/journal.pone.0268924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 05/10/2022] [Indexed: 11/18/2022] Open
Abstract
Listeria monocytogenes is a foodborne pathogen and the causative agent of listeriosis, a disease associated with high fatality (20–30%) and hospitalization rates (>95%). ATP-Binding Cassette (ABC) transporters have been demonstrated to be involved in the general stress response. In previous studies, in-frame deletion mutants of the ABC transporter genes, LMOf2365_1875 and LMOf2365_1877, were constructed and analyzed; however, additional work is needed to investigate the virulence potential of these deletion mutants. In this study, two in vitro methods and one in vivo model were used to investigate the virulence potential of in-frame deletion mutants of ABC transporter genes. First, the invasion efficiency in host cells was measured using the HT-29 human cell line. Second, cell-to-cell spread activity was measured using a plaque forming assay. Lastly, virulence potential of the mutants was tested in the Galleria mellonella wax moth model. Our results demonstrated that the deletion mutant, ⊿LMOf2365_1875, displayed decreased invasion and cell-to-cell spread efficiency in comparison to the wild-type, LMOf2365, indicating that LMOf2365_1875 may be required for virulence. Furthermore, the reduced virulence of these mutants was confirmed using the Galleria mellonella wax moth model. In addition, the expression levels of 15 virulence and stress-related genes were analyzed by RT-PCR assays using stationary phase cells. Our results showed that virulence-related gene expression levels from the deletion mutants were elevated (15/15 genes from ⊿LMOf2365_1877 and 7/15 genes from ⊿LMOf2365_1875) compared to the wild type LMOf2365, suggesting that ABC transporters may negatively regulate virulence gene expression under specific conditions. The expression level of the stress-related gene, clpE, also was increased in both deletion mutants, indicating the involvement of ABC transporters in the stress response. Taken together, our findings suggest that ABC transporters may be used as potential targets to develop new therapeutic strategies to control L. monocytogenes.
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Affiliation(s)
- Yanhong Liu
- Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Wyndmoor, PA, United States of America
- * E-mail:
| | - Brian ByongKwon Yoo
- Centers for Disease Control and Prevention, Atlanta, GA, United States of America
| | - Cheng-An Hwang
- Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Wyndmoor, PA, United States of America
| | - Mira Rakic Martinez
- Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD, United States of America
| | - Atin R. Datta
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, United States of America
| | - Pina M. Fratamico
- Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Wyndmoor, PA, United States of America
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Saint Martin C, Darsonval M, Grégoire M, Caccia N, Midoux L, Berland S, Leroy S, Dubois-Brissonnet F, Desvaux M, Briandet R. Spatial organisation of Listeria monocytogenes and Escherichia coli O157:H7 cultivated in gel matrices. Food Microbiol 2022; 103:103965. [DOI: 10.1016/j.fm.2021.103965] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 12/03/2021] [Accepted: 12/06/2021] [Indexed: 01/01/2023]
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Antimicrobial Activity of Ohelo Berry (Vaccinium calycinum) Juice against Listeria monocytogenes and Its Potential for Milk Preservation. Microorganisms 2022; 10:microorganisms10030548. [PMID: 35336123 PMCID: PMC8953330 DOI: 10.3390/microorganisms10030548] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 02/26/2022] [Accepted: 02/28/2022] [Indexed: 02/05/2023] Open
Abstract
Listeria monocytogenes is a foodborne pathogen and causes illnesses with a high mortality rate in susceptible populations. Several dairy-related outbreaks have been attributed to contamination by L. monocytogenes, which requires antimicrobial interventions to enhance the safety of these products. This study aimed to determine the antimicrobial activity of the ohelo berry (Vaccinium calycinum), a Hawaiian wild relative of cranberry, against L. monocytogenes in culture media and milk products. The effect of ohelo berry juice at its sub-inhibitory concentrations on the physicochemical properties, biofilm formation, and gene expression of L. monocytogenes was also investigated. The minimum inhibitory concentration of ohelo berry juice against L. monocytogenes was 12.5%. The sub-inhibitory concentration of ohelo berry juice (6.25%) significantly increased the auto-aggregation and decreased the hydrophobicity, swimming motility, swarming motility, and biofilm formation capability of L. monocytogenes. The relative expression of genes for motility (flaA), biofilm formation and disinfectant resistance (sigB), invasion (iap), listeriolysin (hly), and phospholipase (plcA) was significantly downregulated in L. monocytogenes treated by the 6.25% juice. L. monocytogenes was significantly inhibited in whole and skim milk supplemented with 50% ohelo berry juice, regardless of the fat content. These findings highlight the potential of ohelo berry as a natural preservative and functional food to prevent L. monocytogenes infection.
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14
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Liang S, Hu X, Wang R, Fang M, Yu Y, Xiao X. The combination of thymol and cinnamaldehyde reduces the survival and virulence of Listeria monocytogenes on autoclaved chicken breast. J Appl Microbiol 2022; 132:3937-3950. [PMID: 35178822 DOI: 10.1111/jam.15496] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 01/24/2022] [Accepted: 02/14/2022] [Indexed: 11/28/2022]
Abstract
AIMS To reveal the antibacterial mechanism of the combination of thymol and cinnamaldehyde to Listeria monocytogenes ATCC 19115 on autoclaved chicken breast. METHODS AND RESULTS In this study, Listeria monocytogenes ATCC 19115 on autoclaved chicken breast was exposed to the stress of 125 μg/mL thymol and 125 μg/mL cinnamaldehyde, and transcriptome analysis was used to reveal the crucial antibacterial mechanism. According to the results, 1303 significantly differentially expressed genes (DEGs) were identified. Treated by thymol and cinnamaldehyde in combination, pyrimidine and branched-chain amino acids biosynthesis of L. monocytogenes were thwarted which impairs its nucleic acid biosynthesis and intracellular metabolism. The up-regulated DEGs involved in membrane composition and function contributed to membrane repair. Besides, pyruvate catabolism and TCA cycle were restrained which brought about the disturbance of amino acid metabolism. ABC transporters were also perturbed, for instance, the uptake of cysteine, D-methionine and betaine was activated, while the uptake of vitamin, iron and carnitine was repressed. Thus, L. monocytogenes tended to activate PTS, glycolysis, glycerol catabolism, and pentose phosphate pathways to obtain energy to adapt to the hostile condition. Noticeably, DEGs involved in virulence factors were totally down-regulated, including genes devoted to encoding flagella, chemotaxis, biofilm formation, internalin as well as virulence gene clusters. CONCLUSIONS The combination of thymol and cinnamaldehyde is effective to reduce the survival and potential virulence of L. monocytogenes on autoclaved chicken breast. SIGNIFICANCE AND IMPACT OF STUDY This work contributes to providing theoretical information for the application and optimization of thymol and cinnamaldehyde in ready-to-eat meat products to inhibit L. monocytogenes.
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Affiliation(s)
- Siwei Liang
- Research Center of Food Safety and Detection, School of Food Sciences and Engineering, South China University of Technology, Guangdong Province, Guangzhou City, 510640, China
| | - Xinyi Hu
- Research Center of Food Safety and Detection, School of Food Sciences and Engineering, South China University of Technology, Guangdong Province, Guangzhou City, 510640, China
| | - Ruifei Wang
- Research Center of Food Safety and Detection, School of Food Sciences and Engineering, South China University of Technology, Guangdong Province, Guangzhou City, 510640, China
| | - Meimei Fang
- Research Center of Food Safety and Detection, School of Food Sciences and Engineering, South China University of Technology, Guangdong Province, Guangzhou City, 510640, China
| | - Yigang Yu
- Research Center of Food Safety and Detection, School of Food Sciences and Engineering, South China University of Technology, Guangdong Province, Guangzhou City, 510640, China
| | - Xinglong Xiao
- Research Center of Food Safety and Detection, School of Food Sciences and Engineering, South China University of Technology, Guangdong Province, Guangzhou City, 510640, China
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15
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Gene Analysis of Listeria monocytogenes Suspended Aggregates Induced by Ralstonia insidiosa Cell-Free Supernatants under Nutrient-Poor Environments. Microorganisms 2021; 9:microorganisms9122591. [PMID: 34946191 PMCID: PMC8704912 DOI: 10.3390/microorganisms9122591] [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: 11/23/2021] [Revised: 12/13/2021] [Accepted: 12/14/2021] [Indexed: 01/08/2023] Open
Abstract
Listeria monocytogenes is a zoonotic food-borne pathogen. The production of food-borne pathogenic bacteria aggregates is considered to be a way to improve their resistance and persistence in the food chain. Ralstonia insidiosa has been shown to induce L. monocytogenes to form suspended aggregates, but induction mechanisms remain unclear. In the study, the effect of R. insidiosa cell-free supernatants cultured in 10% TSB medium (10% RIS) on the formation of L. monocytogenes suspended aggregates was evaluated. Next, the Illumina RNA sequencing was used to compare the transcriptional profiles of L. monocytogenes in 10% TSB medium with and without 10% RIS to identify differentially expressed genes (DEGs). The result of functional annotation analysis of DEGs indicated that these genes mainly participate in two component system, bacterial chemotaxis and flagellar assembly. Then the reaction network of L. monocytogenes suspended aggregates with the presence of 10% RIS was summarized. The gene-deletion strain of L. monocytogenes was constructed by homologous recombination. The result showed that cheA and cheY are key genes in the formation of suspended aggregates. This research is the preliminary verification of suspended aggregates’ RNA sequencing and is helpful to analyze the aggregation mechanisms of food-borne pathogenic bacteria from a new perspective.
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16
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Chakravarty D, Sahukhal G, Arick M, Davis ML, Donaldson JR. Transcriptomic Analysis of Listeria monocytogenes in Response to Bile Under Aerobic and Anaerobic Conditions. Front Microbiol 2021; 12:754748. [PMID: 34867878 PMCID: PMC8636025 DOI: 10.3389/fmicb.2021.754748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 10/18/2021] [Indexed: 11/13/2022] Open
Abstract
Listeria monocytogenes is a gram-positive facultative anaerobic bacterium that causes the foodborne illness listeriosis. The pathogenesis of this bacterium depends on its survival in anaerobic, acidic, and bile conditions encountered throughout the gastrointestinal (GI) tract. This transcriptomics study was conducted to analyze the differences in transcript levels produced under conditions mimicking the GI tract. Changes in transcript levels were analyzed using RNA isolated from L. monocytogenes strain F2365 at both aerobic and anaerobic conditions, upon exposure to 0 and 1% bile at acidic and neutral pH. Transcripts corresponding to genes responsible for pathogenesis, cell wall associated proteins, DNA repair, transcription factors, and stress responses had variations in levels under the conditions tested. Upon exposure to anaerobiosis in acidic conditions, there were variations in the transcript levels for the virulence factors internalins, listeriolysin O, etc., as well as many histidine sensory kinases. These data indicate that the response to anaerobiosis differentially influences the transcription of several genes related to the survival of L. monocytogenes under acidic and bile conditions. Though further research is needed to decipher the role of oxygen in pathogenesis of L. monocytogenes, these data provide comprehensive information on how this pathogen responds to the GI tract.
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Affiliation(s)
- Damayanti Chakravarty
- Cell and Molecular Biology, The University of Southern Mississippi, Hattiesburg, MS, United States
| | - Gyan Sahukhal
- Cell and Molecular Biology, The University of Southern Mississippi, Hattiesburg, MS, United States
| | - Mark Arick
- Institute for Genomics, Biocomputing & Biotechnology, Mississippi State University, Mississippi State, MS, United States
| | - Morgan L. Davis
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS, United States
| | - Janet R. Donaldson
- Cell and Molecular Biology, The University of Southern Mississippi, Hattiesburg, MS, United States
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17
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In vitro virulence potential, surface attachment and transcriptional response of sublethally injured Listeria monocytogenes following exposure to peracetic acid. Appl Environ Microbiol 2021; 88:e0158221. [PMID: 34731051 DOI: 10.1128/aem.01582-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The disinfectant Peracetic acid (PAA) can cause high levels of sublethal injury to L. monocytogenes. This study aims to evaluate phenotypic and transcriptional characteristics concerning surface attachment and virulence potential of sublethally injured L. monocytogenes ScottA and EGDe after exposure to 0.75 ppm PAA for 90 min at 4°C and subsequent incubation in TSBY at 4°C. Results showed that injured L. monocytogenes cells (99% of total population) were able to attach (after 2 and 24h) on stainless steel coupons at 4°C and 20°C. In vitro virulence assays using human intestinal epithelial Caco-2 cells showed that injured L. monocytogenes could invade host cells but could not proliferate intracellularly. In vitro virulence response was strain-dependent; injured ScottA was more invasive than EGDe. Assessment of PAA-injury at the transcriptional level showed upregulation of genes (motB, flaA) involved in flagellum motility and surface attachment. The transcriptional response of L. monocytogenes EGDe and ScottA was different; only injured ScottA demonstrated upregulation of the virulence genes inlA and plcA. Downregulation of the stress-related genes fri and kat, and upregulation of lmo0669 was observed in injured ScottA. The obtained results indicate that sublethally-injured L. monocytogenes cells may retain part of their virulence properties as well as their ability to adhere on food processing surfaces. Transmission to food products and introduction of these cells in the food chain is therefore a plausible scenario that is worth taking into consideration in terms of risk assessment. Importance L. monocytogenes is the causative agent of listeriosis a serious food-borne illness. Antimicrobial practices, such as disinfectants used for the elimination of this pathogen in food industry can produce a sublethally injured population fraction. Injured cells of this pathogen, that may survive an antimicrobial treatment, may pose a food safety-risk. Nevertheless, knowledge regarding how sublethal injury may impact important cellular traits and phenotypic responses of this pathogen is limited. This work suggests that sublethally injured L. monocytogenes cells maintain the virulence and surface attachment potential and highlights the importance of the occurrence of sublethally injured cells regarding food safety.
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18
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Functional Genomic Insights into Probiotic Bacillus siamensis Strain B28 from Traditional Korean Fermented Kimchi. Foods 2021; 10:foods10081906. [PMID: 34441683 PMCID: PMC8394110 DOI: 10.3390/foods10081906] [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: 06/22/2021] [Revised: 08/11/2021] [Accepted: 08/13/2021] [Indexed: 01/22/2023] Open
Abstract
Bacillus siamensis strain B28 was previously isolated from traditional Korean fermented kimchi and inhibited expression of the microphthalmia-associated transcription factor and β-catenin in human embryonic kidney 293 cells. Here, we determined the complete genome sequence of strain B28 and compared it with other strains to elucidate its potential probiotic properties. Strain B28 does not contain antibiotic resistance-, hemolysin- or enterotoxin-encoding genes. The genome includes genes related to survival in extreme conditions, adhesion in the gut, and synthesis of the bacteriocin. Considering the potential for enhancement of human health, the strain B28 genome encodes genes related to production of eight essential amino acids, γ-aminobutyric acid, branched-chain fatty acids, γ-glutamyltransferase, and subtilisin. There are genes for the synthesis of uracil, lipoteichoic acid, glutathione, and several reactive oxygen species-scavenging enzymes. Experimentally, strain B28 exhibited sensitivity to eight antibiotics and antibacterial activity against seven foodborne pathogens. B. siamensis B28 is a safe strain with potential for development as a probiotic.
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19
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Yan C, Li X, Zhang G, Zhu Y, Bi J, Hao H, Hou H. Quorum Sensing-Mediated and Growth Phase-Dependent Regulation of Metabolic Pathways in Hafnia alvei H4. Front Microbiol 2021; 12:567942. [PMID: 33737914 PMCID: PMC7960787 DOI: 10.3389/fmicb.2021.567942] [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] [Received: 05/31/2020] [Accepted: 01/26/2021] [Indexed: 11/13/2022] Open
Abstract
Quorum sensing (QS) is a widespread regulatory mechanism in bacteria used to coordinate target gene expression with cell density. Thus far, little is known about the regulatory relationship between QS and cell density in terms of metabolic pathways in Hafnia alvei H4. In this study, transcriptomics analysis was performed under two conditions to address this question. The comparative transcriptome of H. alvei H4 wild-type at high cell density (OD600 = 1.7) relative to low cell density (OD600 = 0.3) was considered as growth phase-dependent manner (GPDM), and the transcriptome profile of luxI/R deletion mutant (ΔluxIR) compared to the wild-type was considered as QS-mediated regulation. In all, we identified 206 differentially expressed genes (DEGs) mainly presented in chemotaxis, TCA cycle, two-component system, ABC transporters and pyruvate metabolism, co-regulated by the both density-dependent regulation, and the results were validated by qPCR and swimming phenotypic assays. Aside from the co-regulated DEGs, we also found that 59 DEGs, mediated by density-independent QS, function in pentose phosphate and histidine metabolism and that 2084 cell-density-dependent DEGs involved in glycolysis/gluconeogenesis and phenylalanine metabolism were influenced only by GPDM from significantly enriched analysis of transcriptome data. The findings provided new information about the interplay between two density-dependent metabolic regulation, which could assist with the formulation of control strategies for this opportunistic pathogen, especially at high cell density.
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Affiliation(s)
- Congyang Yan
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Xue Li
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Gongliang Zhang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Yaolei Zhu
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Jingran Bi
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Hongshun Hao
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Hongman Hou
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
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20
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Luo JC, Long H, Zhang J, Zhao Y, Sun L. Characterization of a Deep Sea Bacillus toyonensis Isolate: Genomic and Pathogenic Features. Front Cell Infect Microbiol 2021; 11:629116. [PMID: 33777842 PMCID: PMC7988205 DOI: 10.3389/fcimb.2021.629116] [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: 11/13/2020] [Accepted: 02/01/2021] [Indexed: 01/09/2023] Open
Abstract
Bacillus toyonensis is a group of Gram-positive bacteria belonging to the Bacillus cereus group and used in some cases as probiotics or biocontrol agents. To our knowledge, B. toyonensis from the deep sea (depth >1,000 m) has not been documented. Here, we report the isolation and characterization of a B. toyonensis strain, P18, from a deep sea hydrothermal field. P18 is aerobic, motile, and able to grow at low temperatures (4°C) and high concentrations of NaCl (8%). P18 possesses a circular chromosome of 5,250,895 bp and a plasmid of 536,892 bp, which encode 5,380 and 523 genes, respectively. Of these genes, 2,229 encode hypothetical proteins that could not be annotated based on the COG database. Comparative genomic analysis showed that P18 is most closely related to the type strain of B. toyonensis, BCT-7112T. Compared to BCT-7112T, P18 contains 1,401 unique genes, 441 of which were classified into 20 COG functional categories, and the remaining 960 genes could not be annotated. A total of 319 putative virulence genes were identified in P18, including toxin-related genes, and 24 of these genes are absent in BCT-7112T. P18 exerted strong cytopathic effects on fish and mammalian cells that led to rapid cell death. When inoculated via injection into fish and mice, P18 rapidly disseminated in host tissues and induced acute infection and mortality. Histopathology revealed varying degrees of tissue lesions in the infected animals. Furthermore, P18 could survive in fish and mouse sera and possessed hemolytic activity. Taken together, these results provide the first evidence that virulent B. toyonensis exists in deep sea environments.
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Affiliation(s)
- Jing-Chang Luo
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China.,College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Hao Long
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
| | - Jian Zhang
- School of Ocean, Yan Tai University, Yantai, China
| | - Yan Zhao
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
| | - Li Sun
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China.,College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China
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21
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Heo S, Kim JH, Kwak MS, Sung MH, Jeong DW. Functional Annotation Genome Unravels Potential Probiotic Bacillus velezensis Strain KMU01 from Traditional Korean Fermented Kimchi. Foods 2021; 10:foods10030563. [PMID: 33803098 PMCID: PMC7998376 DOI: 10.3390/foods10030563] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 03/04/2021] [Accepted: 03/05/2021] [Indexed: 12/01/2022] Open
Abstract
Bacillus velezensis strain KMU01 showing γ-glutamyltransferase activity as a probiotic candidate was isolated from kimchi. However, the genetic information on strain KMU01 was not clear. Therefore, the current investigation was undertaken to prove the probiotic traits of B. velezensis strain KMU01 through genomic analysis. Genomic analysis revealed that strain KMU01 did not encode enterotoxin genes and acquired antibiotic resistance genes. Strain KMU01 genome possessed survivability traits under extreme conditions such as in the presence of gastric acid, as well as several probiotic traits such as intestinal epithelium adhesion and the production of thiamine and essential amino acids. Potential genes for human health enhancement such as those for γ-glutamyltransferase, nattokinase, and bacteriocin production were also identified in the genome. As a starter candidate for food fermentation, the genome of KMU01 encoded for protease, amylase, and lipase genes. The complete genomic sequence of KMU01 will contribute to our understanding of the genetic basis of probiotic properties and allow for the assessment of the effectiveness of this strain as a starter or probiotic for use in the food industry.
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Affiliation(s)
- Sojeong Heo
- Department of Food and Nutrition, Dongduk Women’s University, Seoul 02748, Korea;
| | - Jong-Hoon Kim
- The Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 02707, Korea; (J.-H.K.); (M.-S.K.)
| | - Mi-Sun Kwak
- The Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 02707, Korea; (J.-H.K.); (M.-S.K.)
| | - Moon-Hee Sung
- The Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 02707, Korea; (J.-H.K.); (M.-S.K.)
- KookminBio Corporation, Seoul 02826, Korea
- Correspondence: or (M.-H.S.); (D.-W.J.); Tel.: +82-2-910-4808 (M.-H.S.); +82-2-940-4463 (D.-W.J.)
| | - Do-Won Jeong
- Department of Food and Nutrition, Dongduk Women’s University, Seoul 02748, Korea;
- Correspondence: or (M.-H.S.); (D.-W.J.); Tel.: +82-2-910-4808 (M.-H.S.); +82-2-940-4463 (D.-W.J.)
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22
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Antibiofilm activity of shikonin against Listeria monocytogenes and inhibition of key virulence factors. Food Control 2021. [DOI: 10.1016/j.foodcont.2020.107558] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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23
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Ling N, Wang X, Liu D, Shen Y, Zhang D, Ou D, Fan H, Wang J, Ding Y, Zhang J, Wu Q, Ye Y. Role of fliC on biofilm formation, adhesion, and cell motility in Cronobacter malonaticus and regulation of luxS. Food Chem Toxicol 2021; 149:111940. [PMID: 33417975 DOI: 10.1016/j.fct.2020.111940] [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: 09/09/2020] [Revised: 12/07/2020] [Accepted: 12/17/2020] [Indexed: 12/29/2022]
Abstract
Cronobacter malonaticus is one of the important foodborne pathogens causing infections mainly in adults. Biofilm formation, adhesion, and motility in Cronobacter have been documented, but the implying molecular mechanism has received little attention. Here, a comparison in biofilm formation, adhesion ability, and cell motility among wild type (WT), △luxS, and △fliC strains were analyzed using scanning electron microscope (SEM) and confocal laser scanning microscopy (CLSM). The thickest biofilm was formed by WT, followed by △luxS and △fliC. Furthermore, the deletion of fliC caused the loss of cell motility and the failure to flagella biosynthesis and mature biofilm formation. Besides, the adhesion abilities of △luxS and △fliC to biotic cells (LoVo and IEC-6) and abiotic surface (glass) were significantly decreased compared to WT, revealing that fliC might have an important role in the organism's invasion properties. We further demonstrated that the expression of negative regulator (flgM) of flagellin in △luxS was higher than that in WT, which indicated that luxS indirectly contributed to fliC expression. Our findings provided a novel perspective for precaution and control of C. malonaticus through intercepting fliC-mediated adhesion to biotic cells and abiotic surface.
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Affiliation(s)
- Na Ling
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China; Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, 510070, China
| | - Xin Wang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Dengyu Liu
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Yizhong Shen
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Danfeng Zhang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Dexin Ou
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Hongying Fan
- School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Juan Wang
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, 510070, China
| | - Yu Ding
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, 510070, China
| | - Jumei Zhang
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, 510070, China
| | - Qingping Wu
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, 510070, China.
| | - Yingwang Ye
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China; Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, 510070, China.
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24
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Hoque MN, Istiaq A, Clement RA, Gibson KM, Saha O, Islam OK, Abir RA, Sultana M, Siddiki AMAMZ, Crandall KA, Hossain MA. Insights Into the Resistome of Bovine Clinical Mastitis Microbiome, a Key Factor in Disease Complication. Front Microbiol 2020; 11:860. [PMID: 32582039 PMCID: PMC7283587 DOI: 10.3389/fmicb.2020.00860] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Accepted: 04/09/2020] [Indexed: 12/23/2022] Open
Abstract
Bovine clinical mastitis (CM) is one of the most prevalent diseases caused by a wide range of resident microbes. The emergence of antimicrobial resistance in CM bacteria is well-known, however, the genomic resistance composition (the resistome) at the microbiome-level is not well characterized. In this study, we applied whole metagenome sequencing (WMS) to characterize the resistome of the CM microbiome, focusing on antibiotics and metals resistance, biofilm formation (BF), and quorum sensing (QS) along with in vitro resistance assays of six selected pathogens isolated from the same CM samples. The WMS generated an average of 21.13 million reads (post-processing) from 25 CM samples that mapped to 519 bacterial strains, of which 30.06% were previously unreported. We found a significant (P = 0.001) association between the resistomes and microbiome composition with no association with cattle breed, despite significant differences in microbiome diversity among breeds. The in vitro investigation determined that 76.2% of six selected pathogens considered "biofilm formers" actually formed biofilms and were also highly resistant to tetracycline, doxycycline, nalidixic acid, ampicillin, and chloramphenicol and remained sensitive to metals (Cr, Co, Ni, Cu, Zn) at varying concentrations. We also found bacterial flagellar movement and chemotaxis, regulation and cell signaling, and oxidative stress to be significantly associated with the pathophysiology of CM. Thus, identifying CM microbiomes, and analyzing their resistomes and genomic potentials will help improve the optimization of therapeutic schemes involving antibiotics and/or metals usage in the prevention and control of bovine CM.
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Affiliation(s)
- M. Nazmul Hoque
- Department of Microbiology, University of Dhaka, Dhaka, Bangladesh
- Department of Gynecology, Obstetrics and Reproductive Health, Faculty of Veterinary Medicine and Animal Science, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - Arif Istiaq
- Department of Microbiology, University of Dhaka, Dhaka, Bangladesh
- Department of Developmental Neurobiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
| | - Rebecca A. Clement
- Computational Biology Institute, Milken Institute School of Public Health, The George Washington University, Washington, DC, United States
| | - Keylie M. Gibson
- Computational Biology Institute, Milken Institute School of Public Health, The George Washington University, Washington, DC, United States
| | - Otun Saha
- Department of Microbiology, University of Dhaka, Dhaka, Bangladesh
| | - Ovinu Kibria Islam
- Department of Microbiology, University of Dhaka, Dhaka, Bangladesh
- Department of Microbiology, Jashore University of Science and Technology, Jashore, Bangladesh
| | | | - Munawar Sultana
- Department of Microbiology, University of Dhaka, Dhaka, Bangladesh
| | - AMAM Zonaed Siddiki
- Department of Pathology and Parasitology, Chittagong Veterinary and Animal Sciences University, Chittagong, Bangladesh
| | - Keith A. Crandall
- Computational Biology Institute, Milken Institute School of Public Health, The George Washington University, Washington, DC, United States
- Department of Biostatistics and Bioinformatics, Milken Institute School of Public Health, The George Washington University, Washington, DC, United States
| | - M. Anwar Hossain
- Department of Microbiology, University of Dhaka, Dhaka, Bangladesh
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25
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Tandem mass tag-based quantitative proteomic analysis reveal the inhibition mechanism of thyme essential oil against flagellum of Listeria monocytogenes. Food Res Int 2019; 125:108508. [DOI: 10.1016/j.foodres.2019.108508] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 06/03/2019] [Accepted: 06/21/2019] [Indexed: 11/23/2022]
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26
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Tiensuu T, Guerreiro DN, Oliveira AH, O’Byrne C, Johansson J. Flick of a switch: regulatory mechanisms allowing Listeria monocytogenes to transition from a saprophyte to a killer. Microbiology (Reading) 2019; 165:819-833. [DOI: 10.1099/mic.0.000808] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Teresa Tiensuu
- Department of Molecular Biology; Molecular Infection Medicine, Sweden (MIMS); Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Duarte N. Guerreiro
- Bacterial Stress Response Group, Microbiology, School of Natural Sciences, National University of Ireland Galway, Galway H91 TK33, Ireland
| | - Ana H. Oliveira
- Department of Molecular Biology; Molecular Infection Medicine, Sweden (MIMS); Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Conor O’Byrne
- Bacterial Stress Response Group, Microbiology, School of Natural Sciences, National University of Ireland Galway, Galway H91 TK33, Ireland
| | - Jörgen Johansson
- Department of Molecular Biology; Molecular Infection Medicine, Sweden (MIMS); Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
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27
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Phobalysin: Fisheye View of Membrane Perforation, Repair, Chemotaxis and Adhesion. Toxins (Basel) 2019; 11:toxins11070412. [PMID: 31315179 PMCID: PMC6669599 DOI: 10.3390/toxins11070412] [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: 05/29/2019] [Revised: 07/04/2019] [Accepted: 07/11/2019] [Indexed: 11/30/2022] Open
Abstract
Phobalysin P (PhlyP, for photobacterial lysin encoded on a plasmid) is a recently described small β-pore forming toxin of Photobacterium damselae subsp. damselae (Pdd). This organism, belonging to the family of Vibrionaceae, is an emerging pathogen of fish and various marine animals, which occasionally causes life-threatening soft tissue infections and septicemia in humans. By using genetically modified Pdd strains, PhlyP was found to be an important virulence factor. More recently, in vitro studies with purified PhlyP elucidated some basic consequences of pore formation. Being the first bacterial small β-pore forming toxin shown to trigger calcium-influx dependent membrane repair, PhlyP has advanced to a revealing model toxin to study this important cellular function. Further, results from co-culture experiments employing various Pdd strains and epithelial cells together with data on other bacterial toxins indicate that limited membrane damage may generally enhance the association of bacteria with target cells. Thereby, remodeling of plasma membrane and cytoskeleton during membrane repair could be involved. In addition, a chemotaxis-dependent attack-and track mechanism influenced by environmental factors like salinity may contribute to PhlyP-dependent association of Pdd with cells. Obviously, a synoptic approach is required to capture the regulatory links governing the interaction of Pdd with target cells. The characterization of Pdd’s secretome may hold additional clues because it may lead to the identification of proteases activating PhlyP’s pro-form. Current findings on PhlyP support the notion that pore forming toxins are not just killer proteins but serve bacteria to fulfill more subtle functions, like accessing their host.
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28
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Song X, Hou M, Tu J, Xue M, Shao Y, Jiang H, Liu H, Xue T, Wang G, Qi K. Outer membrane proteins YbjX and PagP co-regulate motility in Escherichia coli via the bacterial chemotaxis pathway. Res Vet Sci 2019; 125:279-284. [PMID: 31326704 DOI: 10.1016/j.rvsc.2019.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 05/25/2019] [Accepted: 07/10/2019] [Indexed: 02/08/2023]
Abstract
Mutation of the PhoP/Q two-component system decreases the expression of ybjX and pagP encoding outer membrane proteins, and mutation of ybjX or pagP attenuates avian pathogenic Escherichia coli (APEC) pathogenicity. However, whether ybjX/pagP mutation (double-deletion mutant) has a synergistic effect on pathogenicity remains unknown. Herein, electrophoresis mobility shift assay (EMSA) experiments showed that the PhoP/Q system regulated ybjX and pagP transcription indirectly. The APECΔybjX/pagP mutant strain, constructed using the Red recombination method, exhibited reduced invasion of chicken embryo fibroblast (DF-1) cells, but had no effect on virulence in a chicken model. Using RNA sequencing to identify differential mRNAs in APECΔybjXΔpagP and native strains, we revealed up-regulation of genes involved in the bacterial chemotaxis pathway. The ybjX/pagP mutant strain displayed significantly increased motility, suggesting that double deletion of ybjX and pagP enhances motility via the bacterial chemotaxis pathway.
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Affiliation(s)
- Xiangjun Song
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Manman Hou
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Jian Tu
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Mei Xue
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Ying Shao
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Huyan Jiang
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Hongmei Liu
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Ting Xue
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Guijun Wang
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Kezong Qi
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China.
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29
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Johansson J, Freitag NE. Regulation of Listeria monocytogenes Virulence. Microbiol Spectr 2019; 7:10.1128/microbiolspec.gpp3-0064-2019. [PMID: 31441398 PMCID: PMC10957223 DOI: 10.1128/microbiolspec.gpp3-0064-2019] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Indexed: 02/07/2023] Open
Abstract
Whereas obligate human and animal bacterial pathogens may be able to depend upon the warmth and relative stability of their chosen replication niche, environmental bacteria such as Listeria monocytogenes that harbor the ability to replicate both within animal cells and in the outside environment must maintain the capability to manage life under a variety of disparate conditions. Bacterial life in the outside environment requires adaptation to wide ranges of temperature, available nutrients, and physical stresses such as changes in pH and osmolarity as well as desiccation. Following ingestion by a susceptible animal host, the bacterium must adapt to similar changes during transit through the gastrointestinal tract and overcome a variety of barriers associated with host innate immune responses. Rapid alteration of patterns of gene expression and protein synthesis represent one strategy for quickly adapting to a dynamic host landscape. Here, we provide an overview of the impressive variety of strategies employed by the soil-dwelling, foodborne, mammalian pathogen L. monocytogenes to straddle diverse environments and optimize bacterial fitness both inside and outside host cells.
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Affiliation(s)
- Jörgen Johansson
- Department of Molecular Biology, Laboratory for Molecular Infection Medicine Sweden (MIMS) and Umeå Centre for Microbial Research (UCMR), Umeå University, 90187 Umeå, Sweden
| | - Nancy E Freitag
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago IL
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30
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Santos T, Viala D, Chambon C, Esbelin J, Hébraud M. Listeria monocytogenes Biofilm Adaptation to Different Temperatures Seen Through Shotgun Proteomics. Front Nutr 2019; 6:89. [PMID: 31259174 PMCID: PMC6587611 DOI: 10.3389/fnut.2019.00089] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 05/24/2019] [Indexed: 12/16/2022] Open
Abstract
Listeria monocytogenes is a foodborne pathogen that can cause invasive severe human illness (listeriosis) in susceptible patients. Most human listeriosis cases appear to be caused by consumption of refrigerated ready-to-eat foods. Although initial contamination levels in foods are usually low, the ability of these bacteria to survive and multiply at low temperatures allows it to reach levels high enough to cause disease. This study explores the set of proteins that might have an association with L. monocytogenes adaptation to different temperatures. Cultures were grown in biofilm, the most widespread mode of growth in natural and industrial realms. Protein extractions were performed from three different growth temperatures (10, 25, and 37°C) and two growth phases (early stage and mature biofilm). L. monocytogenes subproteomes were targeted using three extraction methods: trypsin-enzymatic shaving, biotin-labeling and cell fractionation. The different subproteomes obtained were separated and analyzed by shotgun proteomics using high-performance liquid chromatography combined with tandem mass spectrometry (LC-OrbiTrap LTQVelos, ThermoFisher Scientific). A total of 141 (biotinylation), 98 (shaving) and 910 (fractionation) proteins were identified. Throughout the 920 unique proteins identified, many are connected to basic cell functions, but some are linked with thermoregulation. We observed some noteworthy protein abundance shifts associated with the major adaptation to cold mechanisms present in L. monocytogenes, namely: the role of ribosomes and the stressosome with a higher abundance of the general stress protein Ctc (Rl25) and the general stress transcription factor sigma B (σB), changes in cell fluidity and motility seen by higher levels of foldase protein PrsA2 and flagellin (FlaA), the uptake of osmolytes with a higher abundance of glycine betaine (GbuB) and carnitine transporters (OpucA), and the relevance of the overexpression of chaperone proteins such as cold shock proteins (CspLA and Dps). As for 37°C, we observed a significantly higher percentage of proteins associated with transcriptional or translational activity present in higher abundance upon comparison with the colder settings. These contrasts of protein expression throughout several conditions will enrich databases and help to model the regulatory circuitry that drives adaptation of L. monocytogenes to environments.
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Affiliation(s)
- Tiago Santos
- Université Clermont Auvergne, INRA, UMR Microbiologie Environnement Digestif Santé (MEDiS), Saint-Genès-Champanelle, France
| | - Didier Viala
- INRA, Plateforme d'Exploration du Métabolisme, Composante Protéomique (PFEMcp), Saint-Genès-Champanelle, France
| | - Christophe Chambon
- INRA, Plateforme d'Exploration du Métabolisme, Composante Protéomique (PFEMcp), Saint-Genès-Champanelle, France
| | - Julia Esbelin
- Université Clermont Auvergne, INRA, UMR Microbiologie Environnement Digestif Santé (MEDiS), Saint-Genès-Champanelle, France
| | - Michel Hébraud
- Université Clermont Auvergne, INRA, UMR Microbiologie Environnement Digestif Santé (MEDiS), Saint-Genès-Champanelle, France
- INRA, Plateforme d'Exploration du Métabolisme, Composante Protéomique (PFEMcp), Saint-Genès-Champanelle, France
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31
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Gu HJ, Sun QL, Luo JC, Zhang J, Sun L. A First Study of the Virulence Potential of a Bacillus subtilis Isolate From Deep-Sea Hydrothermal Vent. Front Cell Infect Microbiol 2019; 9:183. [PMID: 31214515 PMCID: PMC6554283 DOI: 10.3389/fcimb.2019.00183] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 05/13/2019] [Indexed: 02/05/2023] Open
Abstract
Bacillus subtilis is the best studied Gram-positive bacterium, primarily as a model of cell differentiation and industrial exploitation. To date, little is known about the virulence of B. subtilis. In this study, we examined the virulence potential of a B. subtilis strain (G7) isolated from the Iheya North hydrothermal field of Okinawa Trough. G7 is aerobic, motile, endospore-forming, and requires NaCl for growth. The genome of G7 is composed of one circular chromosome of 4,216,133 base pairs with an average GC content of 43.72%. G7 contains 4,416 coding genes, 27.5% of which could not be annotated, and the remaining 72.5% were annotated with known or predicted functions in 25 different COG categories. Ten sets of 23S, 5S, and 16S ribosomal RNA operons, 86 tRNA and 14 sRNA genes, 50 tandem repeats, 41 mini-satellites, one microsatellite, and 42 transposons were identified in G7. Comparing to the genome of the B. subtilis wild type strain NCIB 3610T, G7 genome contains many genomic translocations, inversions, and insertions, and twice the amount of genomic Islands (GIs), with 42.5% of GI genes encoding hypothetical proteins. G7 possesses abundant putative virulence genes associated with adhesion, invasion, dissemination, anti-phagocytosis, and intracellular survival. Experimental studies showed that G7 was able to cause mortality in fish and mice following intramuscular/intraperitoneal injection, resist the killing effect of serum complement, and replicate in mouse macrophages and fish peripheral blood leukocytes. Taken together, our study indicates that G7 is a B. subtilis isolate with unique genetic features and can be lethal to vertebrate animals once being introduced into the animals by artificial means. These results provide the first insight into the potential harmfulness of deep-sea B. subtilis.
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Affiliation(s)
- Han-Jie Gu
- CAS Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China.,College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Qing-Lei Sun
- CAS Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
| | - Jing-Chang Luo
- CAS Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China.,College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Jian Zhang
- CAS Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
| | - Li Sun
- CAS Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
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32
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Karthikeyan R, Gayathri P, Gunasekaran P, Jagannadham MV, Rajendhran J. Comprehensive proteomic analysis and pathogenic role of membrane vesicles of Listeria monocytogenes serotype 4b reveals proteins associated with virulence and their possible interaction with host. Int J Med Microbiol 2019; 309:199-212. [PMID: 30962079 DOI: 10.1016/j.ijmm.2019.03.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 03/19/2019] [Accepted: 03/25/2019] [Indexed: 02/07/2023] Open
Abstract
Membrane vesicles (MVs) are produced by various Gram positive and Gram negative pathogenic bacteria and play an important role in virulence. In this study, the membrane vesicles (MVs) of L. monocytogenes were isolated from the culture supernatant. High-resolution electron microscopy and dynamic light scattering analysis revealed that L. monocytogenes MVs are spherical with a diameter of 200 to 300 nm in size. Further, comprehensive proteomic analyses of MVs and whole cells of L. monocytogenes were performed using LC/MS/MS. A total of 1355 and 312 proteins were identified in the L. monocytogenes cells and MVs, respectively. We identified that 296 proteins are found in both whole cells, and MV proteome and 16 proteins were identified only in the MVs. Also, we have identified the virulence factors such as listeriolysin O (LLO), internalin B (InlB), autolysin, p60, NLP/P60 family protein, UPF0356 protein, and PLC-A in MVs. Computational prediction of host-MV interactions revealed a total of 1841 possible interactions with the host involving 99 MV proteins and 1513 host proteins. We elucidated the possible pathway that mediates internalization of L. monocytogenes MV to host cells and the subsequent pathogenesis mechanisms. The in vitro infection assays showed that the purified MVs could induce cytotoxicity in Caco-2 cells. Using endocytosis inhibitors, we demonstrated that MVs are internalized via actin-mediated endocytosis. These results suggest that L. monocytogenes MVs can interact with host cell and contribute to the pathogenesis of L. monocytogenes during infection.
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Affiliation(s)
- Raman Karthikeyan
- Department of Genetics, School of Biological Sciences, Madurai Kamaraj University, Madurai, 625021, Tamil Nadu, India
| | - Pratapa Gayathri
- CSIR - Centre for Cellular and Molecular Biology, Tarnaka, Hyderabad, 500007, India
| | | | | | - Jeyaprakash Rajendhran
- Department of Genetics, School of Biological Sciences, Madurai Kamaraj University, Madurai, 625021, Tamil Nadu, India.
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33
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Bacterial chemotaxis coupling protein: Structure, function and diversity. Microbiol Res 2019; 219:40-48. [DOI: 10.1016/j.micres.2018.11.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 10/29/2018] [Accepted: 11/02/2018] [Indexed: 01/10/2023]
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34
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Chen G, Cao M, Yu J, Guo X, Shi S. Prediction and functional analysis of prokaryote lysine acetylation site by incorporating six types of features into Chou's general PseAAC. J Theor Biol 2019; 461:92-101. [DOI: 10.1016/j.jtbi.2018.10.047] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 10/09/2018] [Accepted: 10/22/2018] [Indexed: 12/12/2022]
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35
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Boncan DAT, David AME, Lluisma AO. A CAZyme-Rich Genome of a Taxonomically Novel Rhodophyte-Associated Carrageenolytic Marine Bacterium. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2018; 20:685-705. [PMID: 29936557 DOI: 10.1007/s10126-018-9840-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 06/07/2018] [Indexed: 06/08/2023]
Abstract
Carbohydrate-active enzymes (CAZymes) have significant biotechnological potential as agents for degradation or modification of polysaccharides/glycans. As marine macroalgae are known to be rich in various types of polysaccharides, seaweed-associated bacteria are likely to be a good source of these CAZymes. A genomics approach can be used to explore CAZyme abundance and diversity, but it can also provide deep insights into the biology of CAZyme producers and, in particular, into molecular mechanisms that mediate their interaction with their hosts. In this study, a Gram-negative, aerobic, rod-shaped, carrageenolytic, and culturable marine bacterium designated as AOL6 was isolated from a diseased thallus of a carrageenan-producing farmed rhodophyte, Kappaphycus alvarezii (Gigartinales, Rhodophyta). The whole genome of this bacterium was sequenced and characterized. Sequence reads were assembled producing a high-quality genome assembly. The estimated genome size of the bacterium is 4.4 Mb and a G+C content of 52%. Molecular phylogenetic analysis based on a complete sequence of 16S rRNA, rpoB, and a set of 38 single-copy genes suggests that the bacterium is an unknown species and represents a novel genus in the family Cellvibrionaceae that is most closely related to the genera Teredinibacter and Saccharophagus. Genome comparison with T. turnerae T7901 and S. degradans 2-40 reveals several features shared by the three species, including a large number of CAZymes that comprised > 5% of the total number of protein-coding genes. The high proportion of CAZymes found in the AOL6 genome exceeds that of other known carbohydrate degraders, suggesting a significant capacity to degrade a range of polysaccharides including κ-carrageenan; 34% of these CAZymes have signal peptide sequences for secretion. Three putative κ-carrageenase-encoding genes were identified from the genome of the bacterium via in silico analysis, consistent with the results of the zymography assay (with κ-carrageenan as substrate). Genome analysis also indicated that AOL6 relies exclusively on type 2 secretion system (T2SS) for secreting proteins (possibly including glycoside hydrolases). In relation to T2SS, the product of the pilZ gene was predicted to be highly expressed, suggesting specialization for cell adhesion and secretion of virulence factors. The assignment of proteins to clusters of orthologous groups (COGs) revealed a pattern characteristic of r-strategists. Majority of two-component system proteins identified in the AOL6 genome were also predicted to be involved in chemotaxis and surface colonization. These genomic features suggest that AOL6 is an opportunistic pathogen, adapted to colonizing polysaccharide-rich hosts, including carrageenophytes.
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Affiliation(s)
- Delbert Almerick T Boncan
- Marine Science Institute, College of Science, University of the Philippines Diliman, 1101, Quezon City, Philippines
- National Institute of Molecular Biology and Biotechnology, College of Science, University of the Philippines Diliman, 1101, Quezon City, Philippines
| | - Anne Marjorie E David
- Marine Science Institute, College of Science, University of the Philippines Diliman, 1101, Quezon City, Philippines
- Institute of Biology, College of Science, University of the Philippines Diliman, 1101, Quezon City, Philippines
| | - Arturo O Lluisma
- Marine Science Institute, College of Science, University of the Philippines Diliman, 1101, Quezon City, Philippines.
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36
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Tawk C, Nigro G, Rodrigues Lopes I, Aguilar C, Lisowski C, Mano M, Sansonetti P, Vogel J, Eulalio A. Stress-induced host membrane remodeling protects from infection by non-motile bacterial pathogens. EMBO J 2018; 37:embj.201798529. [PMID: 30389666 PMCID: PMC6276891 DOI: 10.15252/embj.201798529] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 10/05/2018] [Accepted: 10/10/2018] [Indexed: 01/01/2023] Open
Abstract
While mucosal inflammation is a major source of stress during enteropathogen infection, it remains to be fully elucidated how the host benefits from this environment to clear the pathogen. Here, we show that host stress induced by different stimuli mimicking inflammatory conditions strongly reduces the binding of Shigella flexneri to epithelial cells. Mechanistically, stress activates acid sphingomyelinase leading to host membrane remodeling. Consequently, knockdown or pharmacological inhibition of the acid sphingomyelinase blunts the stress-dependent inhibition of Shigella binding to host cells. Interestingly, stress caused by intracellular Shigella replication also results in remodeling of the host cell membrane, in vitro and in vivo, which precludes re-infection by this and other non-motile pathogens. In contrast, Salmonella Typhimurium overcomes the shortage of permissive entry sites by gathering effectively at the remaining platforms through its flagellar motility. Overall, our findings reveal host membrane remodeling as a novel stress-responsive cell-autonomous defense mechanism that protects epithelial cells from infection by non-motile bacterial pathogens.
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Affiliation(s)
- Caroline Tawk
- Host RNA Metabolism Group, Institute for Molecular Infection Biology (IMIB), University of Würzburg, Würzburg, Germany.,RNA Biology Group, Institute for Molecular Infection Biology (IMIB), University of Würzburg, Würzburg, Germany
| | - Giulia Nigro
- Molecular Microbial Pathogenesis Laboratory, Institut Pasteur, Paris, France
| | - Ines Rodrigues Lopes
- Functional Genomics and RNA-based Therapeutics, UC-BIOTECH, Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal.,RNA & Infection Group, UC-BIOTECH, Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal
| | - Carmen Aguilar
- Host RNA Metabolism Group, Institute for Molecular Infection Biology (IMIB), University of Würzburg, Würzburg, Germany
| | - Clivia Lisowski
- Host RNA Metabolism Group, Institute for Molecular Infection Biology (IMIB), University of Würzburg, Würzburg, Germany
| | - Miguel Mano
- Functional Genomics and RNA-based Therapeutics, UC-BIOTECH, Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal
| | - Philippe Sansonetti
- Molecular Microbial Pathogenesis Laboratory, Institut Pasteur, Paris, France
| | - Jörg Vogel
- RNA Biology Group, Institute for Molecular Infection Biology (IMIB), University of Würzburg, Würzburg, Germany.,Helmholtz Institute for RNA-Based Infection Research (HIRI), Würzburg, Germany
| | - Ana Eulalio
- Host RNA Metabolism Group, Institute for Molecular Infection Biology (IMIB), University of Würzburg, Würzburg, Germany .,RNA & Infection Group, UC-BIOTECH, Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal
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37
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Marini E, Magi G, Ferretti G, Bacchetti T, Giuliani A, Pugnaloni A, Rippo MR, Facinelli B. Attenuation of Listeria monocytogenes Virulence by Cannabis sativa L. Essential Oil. Front Cell Infect Microbiol 2018; 8:293. [PMID: 30186775 PMCID: PMC6113369 DOI: 10.3389/fcimb.2018.00293] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 07/31/2018] [Indexed: 12/15/2022] Open
Abstract
Anti-virulence strategies are being explored as a novel approach to combat pathogens. Such strategies include inhibition of surface adhesion, tissue invasion, toxin production, and/or interference with the gene regulation of other virulence traits. Listeria monocytogenes, the causative agent of listeriosis, is a facultative intracellular food pathogen characterized by a wide distribution in the environment. Its ability to persist within biofilms and to develop resistance to sanitizers is the cause of significant problems in food processing plants and of steep costs for the food industry. In humans, the treatment of listeriosis is hampered by the intracellular location of listeriae and the poor intracellular penetration of some antibiotics. Eleven L. monocytogenes isolates from patients who were diagnosed with invasive listeriosis in Italy in 2014-2016 were studied. This in vitro and in vivo study explored the antibacterial and anti-virulence properties of a steam-distilled essential oil of Cannabis sativa L., which is being intensively investigated for its high content in powerful bioactive phytochemicals. Susceptibility experiments demonstrated a moderate bactericidal activity of the essential oil (Minimum Bactericidal Concentration > 2048 μg/mL). Assessment of the effects of sublethal concentrations of the essential oil on L. monocytogenes virulence traits demonstrated a significant action on motility. Listeriae were non-motile after exposure to the essential oil. Light and scanning electron microscopy documented aggregates of listeriae with the flagella trapped inside the cluster. Real-time RT-PCR experiments showed downregulation of flagellar motility genes and of the regulatory gene prfA. The ability to form biofilm and to invade Caco-2 cells was also significantly reduced. Galleria mellonella larvae infected with L. monocytogenes grown in presence of sublethal concentrations of the essential oil showed much higher survival rates compared with controls, suggesting that the extract inhibited tissue invasion. Food contamination with L. monocytogenes is a major concern for the food industry, particularly for plants making ready-to-eat and processed food. The present work provides a baseline in the study of the anti-virulence properties of the C. sativa essential oil against L. monocytogenes. Further studies are needed to understand if it could be used as an alternative agent for the control of L. monocytogenes in food processing plants.
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Affiliation(s)
- Emanuela Marini
- Unit of Microbiology, Department of Biomedical Sciences and Public Health, Polytechnic University of Marche, Ancona, Italy
| | - Gloria Magi
- Unit of Microbiology, Department of Biomedical Sciences and Public Health, Polytechnic University of Marche, Ancona, Italy
| | - Gianna Ferretti
- Department of Clinical Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Tiziana Bacchetti
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Angelica Giuliani
- Division of Pathology, Department of Clinical and Molecular Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Armanda Pugnaloni
- Division of Pathology, Department of Clinical and Molecular Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Maria Rita Rippo
- Division of Pathology, Department of Clinical and Molecular Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Bruna Facinelli
- Unit of Microbiology, Department of Biomedical Sciences and Public Health, Polytechnic University of Marche, Ancona, Italy
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Crespo Tapia N, den Besten HM, Abee T. Glycerol metabolism induces Listeria monocytogenes biofilm formation at the air-liquid interface. Int J Food Microbiol 2018; 273:20-27. [DOI: 10.1016/j.ijfoodmicro.2018.03.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 03/12/2018] [Accepted: 03/13/2018] [Indexed: 11/26/2022]
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An AlgU-Regulated Antisense Transcript Encoded within the Pseudomonas syringae fleQ Gene Has a Positive Effect on Motility. J Bacteriol 2018; 200:JB.00576-17. [PMID: 29311280 DOI: 10.1128/jb.00576-17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 01/04/2018] [Indexed: 12/29/2022] Open
Abstract
Production of bacterial flagella is controlled by a multitiered regulatory system that coordinates the expression of 40 to 50 subunits and ordered assembly of these elaborate structures. Flagellar expression is environmentally controlled, presumably to optimize the benefits and liabilities of having these organelles on cell growth and survival. We recently reported a global survey of AlgU-dependent regulation and binding in Pseudomonas syringae pv. tomato DC3000 that included evidence for strong downregulation of many flagellar and chemotaxis motility genes. Here, we returned to those data to look for other AlgU-dependent influences on the flagellar regulatory network. We identified an AlgU-dependent antisense transcript expressed from within the fleQ gene, the master regulator of flagellar biosynthesis in Pseudomonas We tested whether expression of this antisense RNA influenced bacterial behavior and found that it reduces AlgU-dependent downregulation of motility. Importantly, this antisense expression influenced motility only under conditions in which AlgU was expressed. Comparative sequence analysis of the locus containing the antisense transcript's AlgU-dependent promoter in over 300 Pseudomonas genomes revealed sequence conservation in most strains that encode AlgU. This suggests that the antisense transcript plays an important role that is conserved across most of the genus Pseudomonas IMPORTANCE Pseudomonas syringae is a globally distributed host-specific bacterial pathogen that causes disease in a wide-range of plants. An elaborate gene expression regulation network controls flagellum production, which is important for proper flagellum assembly and a key aspect of certain lifestyle transitions. P. syringae pv. tomato DC3000 uses flagellum-powered motility in the early stages of host colonization and adopts a sessile lifestyle after entering plant tissues, but the regulation of this transition is not understood. Our work demonstrates a link between regulation of motility and global transcriptional control that facilitates bacterial growth and disease in plants. Additionally, sequence comparisons suggest that this regulation mechanism is conserved in most members of the genus Pseudomonas.
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Guariglia-Oropeza V, Orsi RH, Guldimann C, Wiedmann M, Boor KJ. The Listeria monocytogenes Bile Stimulon under Acidic Conditions Is Characterized by Strain-Specific Patterns and the Upregulation of Motility, Cell Wall Modification Functions, and the PrfA Regulon. Front Microbiol 2018; 9:120. [PMID: 29467736 PMCID: PMC5808219 DOI: 10.3389/fmicb.2018.00120] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 01/18/2018] [Indexed: 11/16/2022] Open
Abstract
Listeria monocytogenes uses a variety of transcriptional regulation strategies to adapt to the extra-host environment, the gastrointestinal tract, and the intracellular host environment. While the alternative sigma factor SigB has been proposed to be a key transcriptional regulator that facilitates L. monocytogenes adaptation to the gastrointestinal environment, the L. monocytogenes' transcriptional response to bile exposure is not well-understood. RNA-seq characterization of the bile stimulon was performed in two L. monocytogenes strains representing lineages I and II. Exposure to bile at pH 5.5 elicited a large transcriptomic response with ~16 and 23% of genes showing differential transcription in 10403S and H7858, respectively. The bile stimulon includes genes involved in motility and cell wall modification mechanisms, as well as genes in the PrfA regulon, which likely facilitate survival during the gastrointestinal stages of infection that follow bile exposure. The fact that bile exposure induced the PrfA regulon, but did not induce further upregulation of the SigB regulon (beyond that expected by exposure to pH 5.5), suggests a model where at the earlier stages of gastrointestinal infection (e.g., acid exposure in the stomach), SigB-dependent gene expression plays an important role. Subsequent exposure to bile induces the PrfA regulon, potentially priming L. monocytogenes for subsequent intracellular infection stages. Some members of the bile stimulon showed lineage- or strain-specific distribution when 27 Listeria genomes were analyzed. Even though sigB null mutants showed increased sensitivity to bile, the SigB regulon was not found to be upregulated in response to bile beyond levels expected by exposure to pH 5.5. Comparison of wildtype and corresponding ΔsigB strains newly identified 26 SigB-dependent genes, all with upstream putative SigB-dependent promoters.
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Affiliation(s)
| | - Renato H Orsi
- Food Safety Laboratory, Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Claudia Guldimann
- Food Safety Laboratory, Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Martin Wiedmann
- Food Safety Laboratory, Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Kathryn J Boor
- Food Safety Laboratory, Department of Food Science, Cornell University, Ithaca, NY, United States
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Schardt J, Jones G, Müller-Herbst S, Schauer K, D'Orazio SEF, Fuchs TM. Comparison between Listeria sensu stricto and Listeria sensu lato strains identifies novel determinants involved in infection. Sci Rep 2017; 7:17821. [PMID: 29259308 PMCID: PMC5736727 DOI: 10.1038/s41598-017-17570-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 11/28/2017] [Indexed: 01/01/2023] Open
Abstract
The human pathogen L. monocytogenes and the animal pathogen L. ivanovii, together with four other species isolated from symptom-free animals, form the “Listeria sensu stricto” clade. The members of the second clade, “Listeria sensu lato”, are believed to be solely environmental bacteria without the ability to colonize mammalian hosts. To identify novel determinants that contribute to infection by L. monocytogenes, the causative agent of the foodborne disease listeriosis, we performed a genome comparison of the two clades and found 151 candidate genes that are conserved in the Listeria sensu stricto species. Two factors were investigated further in vitro and in vivo. A mutant lacking an ATP-binding cassette transporter exhibited defective adhesion and invasion of human Caco-2 cells. Using a mouse model of foodborne L. monocytogenes infection, a reduced number of the mutant strain compared to the parental strain was observed in the small intestine and the liver. Another mutant with a defective 1,2-propanediol degradation pathway showed reduced persistence in the stool of infected mice, suggesting a role of 1,2-propanediol as a carbon and energy source of listeriae during infection. These findings reveal the relevance of novel factors for the colonization process of L. monocytogenes.
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Affiliation(s)
- Jakob Schardt
- ZIEL-Institute for Food & Health, and Lehrstuhl für Mikrobielle Ökologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Weihenstephaner Berg 3, 85354, Freising, Germany
| | - Grant Jones
- Department of Microbiology, Immunology, & Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
| | - Stefanie Müller-Herbst
- ZIEL-Institute for Food & Health, and Lehrstuhl für Mikrobielle Ökologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Weihenstephaner Berg 3, 85354, Freising, Germany
| | - Kristina Schauer
- Lehrstuhl für Hygiene und Technologie der Milch, Tiermedizinische Fakultät, Ludwig-Maximilians-Universität München, Schönleutner Str. 8, 85764, Oberschleißheim, Germany
| | - Sarah E F D'Orazio
- Department of Microbiology, Immunology, & Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
| | - Thilo M Fuchs
- ZIEL-Institute for Food & Health, and Lehrstuhl für Mikrobielle Ökologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Weihenstephaner Berg 3, 85354, Freising, Germany. .,Friedrich-Loeffler-Institut, Institut für Molekulare Pathogenese, Naumburger Str. 96a, 07743, Jena, Germany.
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Eshwar AK, Guldimann C, Oevermann A, Tasara T. Cold-Shock Domain Family Proteins (Csps) Are Involved in Regulation of Virulence, Cellular Aggregation, and Flagella-Based Motility in Listeria monocytogenes. Front Cell Infect Microbiol 2017; 7:453. [PMID: 29124040 PMCID: PMC5662587 DOI: 10.3389/fcimb.2017.00453] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 10/04/2017] [Indexed: 11/13/2022] Open
Abstract
Cold shock-domain family proteins (Csps) are highly conserved nucleic acid binding proteins regulating the expression of various genes including those involved in stress resistance and virulence in bacteria. We show here that Csps are involved in virulence, cell aggregation and flagella-based extracellular motility of Listeria monocytogenes. A L. monocytogenes mutant deleted in all three csp genes (ΔcspABD) is attenuated with respect to human macrophage infection as well as virulence in a zebrafish infection model. Moreover, this mutant is incapable of aggregation and fails to express surface flagella or exhibit swarming motility. An evaluation of double csp gene deletion mutant (ΔcspBD, ΔcspAD and ΔcspAB) strains that produce single csp genes showed that there is redundancy as well as functional differences among the three L. monocytogenes Csps in their contributions to virulence, cellular aggregation, flagella production, and swarming motility. Protein and mRNA expression analysis further showed impaired expression of key virulence and motility genes in the csp mutants. Our observations at protein and mRNA level suggest Csp-dependent expression regulation of these genes at transcriptional and post-transcriptional levels. In a mutant lacking all csp genes (ΔcspABD) as well as those possessing single csp genes (ΔcspBD, ΔcspAD, and ΔcspAB) we detected reduced levels of proteins or activity as well as transcripts from the prfA, hly, mpl, and plcA genes suggesting a Csp-dependent transcriptional regulation of these genes. These csp mutants also had reduced or completely lacked ActA proteins and cell surface flagella but contained elevated actA and flaA mRNA levels compared to the parental wild type strain suggesting Csp involvement in post-transcriptional regulation of these genes. Overall, our results suggest that Csps contribute to the expression regulation of virulence and flagella-associated genes thereby promoting host pathogenicity, cell aggregation and flagella-based motility processes in L. monocytogenes.
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Affiliation(s)
- Athmanya K. Eshwar
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Claudia Guldimann
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Anna Oevermann
- Neuropathology—Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Taurai Tasara
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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Liu Y, Yoo BB, Hwang CA, Suo Y, Sheen S, Khosravi P, Huang L. LMOf2365_0442 Encoding for a Fructose Specific PTS Permease IIA May Be Required for Virulence in L. monocytogenes Strain F2365. Front Microbiol 2017; 8:1611. [PMID: 28900418 PMCID: PMC5581801 DOI: 10.3389/fmicb.2017.01611] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/07/2017] [Indexed: 02/06/2023] Open
Abstract
Listeria monocytogenes is a foodborne pathogen that causes listeriosis, which is a major public health concern due to the high fatality rate. LMOf2365_0442, 0443, and 0444 encode for fructose-specific EIIABC components of phosphotransferase transport system (PTS) permease that is responsible for sugar transport. In previous studies, in-frame deletion mutants of a putative fructose-specific PTS permease (LMOf2365_0442, 0443, and 0444) were constructed and analyzed. However, the virulence potential of these deletion mutants has not been studied. In this study, two in vitro methods were used to analyze the virulence potential of these L. monocytogenes deletion mutants. First, invasion assays were used to measure the invasion efficiencies to host cells using the human HT-29 cell line. Second, plaque forming assays were used to measure cell-to-cell spread in host cells. Our results showed that the deletion mutant ΔLMOf2365_0442 had reduced invasion and cell-to-cell spread efficiencies in human cell line compared to the parental strain LMOf2365, indicating that LMOf2365_0442 encoding for a fructose specific PTS permease IIA may be required for virulence in L. monocytogenes strain F2365. In addition, the gene expression levels of 15 virulence and stress-related genes were analyzed in the stationary phase cells of the deletion mutants using RT-PCR assays. Virulence-related gene expression levels were elevated in the deletion mutants ΔLMOf2365_0442-0444 compared to the wild type parental strain LMOf2365, indicating the down-regulation of virulence genes by this PTS permease in L. monocytogenes. Finally, stress-related gene clpC expression levels were also increased in all of the deletion mutants, suggesting the involvement of this PTS permease in stress response. Furthermore, these deletion mutants displayed the same pressure tolerance and the same capacity for biofilm formation compared to the wild-type parental strain LMOf2365. In summary, our findings suggest that the LMOf2365_0442 gene can be used as a potential target to develop inhibitors for new therapeutic and pathogen control strategies for public health.
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Affiliation(s)
- Yanhong Liu
- Molecular Characterization of Foodborne Pathogens Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, WyndmoorPA, United States
| | - Brian B Yoo
- Clinical and Environmental Microbiology Branch, Division of Healthcare Quality and Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, AtlantaGA, United States
| | - Cheng-An Hwang
- Residue Chemistry and Predictive Microbiology Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, WyndmoorPA, United States
| | - Yujuan Suo
- Institute for Agri-Food Standards and Testing Technology, Shanghai Academy of Agricultural SciencesShanghai, China
| | - Shiowshuh Sheen
- Food Safety Intervention Technologies Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, WyndmoorPA, United States
| | - Parvaneh Khosravi
- Food Safety Intervention Technologies Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, WyndmoorPA, United States
| | - Lihan Huang
- Residue Chemistry and Predictive Microbiology Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, WyndmoorPA, United States
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Irazoki O, Campoy S, Barbé J. The Transient Multidrug Resistance Phenotype of Salmonella enterica Swarming Cells Is Abolished by Sub-inhibitory Concentrations of Antimicrobial Compounds. Front Microbiol 2017; 8:1360. [PMID: 28769915 PMCID: PMC5515874 DOI: 10.3389/fmicb.2017.01360] [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: 04/24/2017] [Accepted: 07/04/2017] [Indexed: 12/12/2022] Open
Abstract
Swarming motility is the rapid and coordinated multicellular migration of bacteria across a moist surface. During swarming, bacterial cells exhibit increased resistance to multiple antibiotics, a phenomenon described as adaptive or transient resistance. In this study, we demonstrate that sub-inhibitory concentrations of cefotaxime, ciprofloxacin, trimethoprim, or chloramphenicol, but not that of amikacin, colistin, kanamycin or tetracycline, impair Salmonella enterica swarming. Chloramphenicol-treated S. enterica cells exhibited a clear decrease in their flagellar content, while treatment with other antibiotics that reduced swarming (cefotaxime, ciprofloxacin, and trimethoprim) inhibited polar chemoreceptor array assembly. Moreover, the increased resistance phenotype acquired by swarming cells was abolished by the presence of these antimicrobials. The same occurred in cells treated with these antimicrobial agents in combination with others that had no effect on swarming motility. Our results reveal the potential of inhibiting swarming ability to enhance the therapeutic effectiveness of antimicrobial agents.
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Affiliation(s)
- Oihane Irazoki
- Departament de Genètica i de Microbiologia, Universitat Autònoma de BarcelonaBarcelona, Spain
| | - Susana Campoy
- Departament de Genètica i de Microbiologia, Universitat Autònoma de BarcelonaBarcelona, Spain
| | - Jordi Barbé
- Departament de Genètica i de Microbiologia, Universitat Autònoma de BarcelonaBarcelona, Spain
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45
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Ren J, Sang Y, Lu J, Yao YF. Protein Acetylation and Its Role in Bacterial Virulence. Trends Microbiol 2017; 25:768-779. [PMID: 28462789 DOI: 10.1016/j.tim.2017.04.001] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 03/21/2017] [Accepted: 04/04/2017] [Indexed: 12/13/2022]
Abstract
Protein acetylation is a universal post-translational modification which is found in both eukaryotes and prokaryotes. This process is achieved enzymatically by the protein acetyltransferase Pat, and nonenzymatically by metabolic intermediates (e.g., acetyl phosphate) in bacteria. Protein acetylation plays a role in bacterial chemotaxis, metabolism, DNA replication, and other cellular processes. Recently, accumulating evidence has suggested that protein acetylation might be involved in bacterial virulence because a number of bacterial virulence factors are acetylated. In this review, we summarize the progress in understanding bacterial protein acetylation and discuss how it mediates bacterial virulence.
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Affiliation(s)
- Jie Ren
- Laboratory of Bacterial Pathogenesis, Department of Microbiology and Immunology, Institutes of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yu Sang
- Laboratory of Bacterial Pathogenesis, Department of Microbiology and Immunology, Institutes of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Jie Lu
- Department of Infectious Diseases, Shanghai Ruijin Hospital, Shanghai 200025, China
| | - Yu-Feng Yao
- Laboratory of Bacterial Pathogenesis, Department of Microbiology and Immunology, Institutes of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; Department of Laboratory Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China.
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46
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Metabolic determinants in Listeria monocytogenes anaerobic listeriolysin O production. Arch Microbiol 2017; 199:827-837. [PMID: 28289786 PMCID: PMC5504256 DOI: 10.1007/s00203-017-1355-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 02/21/2017] [Indexed: 11/21/2022]
Abstract
Listeria monocytogenes is a human pathogen and a facultative anaerobe. To better understand how anaerobic growth affects L. monocytogenes pathogenesis, we first showed that anaerobic growth led to decreased growth and changes in surface morphology. Moreover, compared to aerobically grown bacteria, anaerobically grown L. monocytogenes established higher level of invasion but decreased intracellular growth and actin polymerization in cultured cells. The production of listeriolysin O (LLO) was significantly lower in anaerobic cultures—a phenotype observed in wild type and isogenic mutants lacking transcriptional regulators SigB or CodY or harboring a constitutively active PrfA. To explore potential regulatory mechanisms, we established that the addition of central carbon metabolism intermediates, such as acetate, citrate, fumarate, pyruvate, lactate, and succinate, led to an increase in LLO activity in the anaerobic culture supernatant. These results highlight the regulatory role of central carbon metabolism in L. monocytogenes pathogenesis under anaerobic conditions.
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Upadhyay A, Venkitanarayanan K. In vivo efficacy of trans-cinnamaldehyde, carvacrol, and thymol in attenuating Listeria monocytogenes infection in a Galleria mellonella model. J Nat Med 2016; 70:667-72. [DOI: 10.1007/s11418-016-0990-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 03/25/2016] [Indexed: 11/28/2022]
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48
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Lim YL, Ee R, Yong D, Yu CY, Ang GY, Tee KK, Yin WF, Chan KG. Complete Genome Sequence Analysis of Pandoraea pnomenusa Type Strain DSM 16536(T) Isolated from a Cystic Fibrosis Patient. Front Microbiol 2016; 7:109. [PMID: 26903988 PMCID: PMC4744841 DOI: 10.3389/fmicb.2016.00109] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 01/21/2016] [Indexed: 01/07/2023] Open
Affiliation(s)
- Yan-Lue Lim
- Division of Genetics and Molecular Biology, Faculty of Science, Institute of Biological Sciences, University of Malaya Kuala Lumpur, Malaysia
| | - Robson Ee
- Division of Genetics and Molecular Biology, Faculty of Science, Institute of Biological Sciences, University of Malaya Kuala Lumpur, Malaysia
| | - Delicia Yong
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya Kuala Lumpur, Malaysia
| | - Choo-Yee Yu
- Division of Genetics and Molecular Biology, Faculty of Science, Institute of Biological Sciences, University of Malaya Kuala Lumpur, Malaysia
| | - Geik-Yong Ang
- Division of Genetics and Molecular Biology, Faculty of Science, Institute of Biological Sciences, University of Malaya Kuala Lumpur, Malaysia
| | - Kok-Keng Tee
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya Kuala Lumpur, Malaysia
| | - Wai-Fong Yin
- Division of Genetics and Molecular Biology, Faculty of Science, Institute of Biological Sciences, University of Malaya Kuala Lumpur, Malaysia
| | - Kok-Gan Chan
- Division of Genetics and Molecular Biology, Faculty of Science, Institute of Biological Sciences, University of Malaya Kuala Lumpur, Malaysia
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Lobel L, Herskovits AA. Systems Level Analyses Reveal Multiple Regulatory Activities of CodY Controlling Metabolism, Motility and Virulence in Listeria monocytogenes. PLoS Genet 2016; 12:e1005870. [PMID: 26895237 PMCID: PMC4760761 DOI: 10.1371/journal.pgen.1005870] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 01/22/2016] [Indexed: 02/05/2023] Open
Abstract
Bacteria sense and respond to many environmental cues, rewiring their regulatory network to facilitate adaptation to new conditions/niches. Global transcription factors that co-regulate multiple pathways simultaneously are essential to this regulatory rewiring. CodY is one such global regulator, controlling expression of both metabolic and virulence genes in Gram-positive bacteria. Branch chained amino acids (BCAAs) serve as a ligand for CodY and modulate its activity. Classically, CodY was considered to function primarily as a repressor under rich growth conditions. However, our previous studies of the bacterial pathogen Listeria monocytogenes revealed that CodY is active also when the bacteria are starved for BCAAs. Under these conditions, CodY loses the ability to repress genes (e.g., metabolic genes) and functions as a direct activator of the master virulence regulator gene, prfA. This observation raised the possibility that CodY possesses multiple functions that allow it to coordinate gene expression across a wide spectrum of metabolic growth conditions, and thus better adapt bacteria to the mammalian niche. To gain a deeper understanding of CodY's regulatory repertoire and identify direct target genes, we performed a genome wide analysis of the CodY regulon and DNA binding under both rich and minimal growth conditions, using RNA-Seq and ChIP-Seq techniques. We demonstrate here that CodY is indeed active (i.e., binds DNA) under both conditions, serving as a repressor and activator of different genes. Further, we identified new genes and pathways that are directly regulated by CodY (e.g., sigB, arg, his, actA, glpF, gadG, gdhA, poxB, glnR and fla genes), integrating metabolism, stress responses, motility and virulence in L. monocytogenes. This study establishes CodY as a multifaceted factor regulating L. monocytogenes physiology in a highly versatile manner.
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Affiliation(s)
- Lior Lobel
- The Department of Molecular Microbiology and Biotechnology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Anat A. Herskovits
- The Department of Molecular Microbiology and Biotechnology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
- * E-mail:
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Strategies to Block Bacterial Pathogenesis by Interference with Motility and Chemotaxis. Curr Top Microbiol Immunol 2016; 398:185-205. [PMID: 27000091 DOI: 10.1007/82_2016_493] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Infections by motile, pathogenic bacteria, such as Campylobacter species, Clostridium species, Escherichia coli, Helicobacter pylori, Listeria monocytogenes, Neisseria gonorrhoeae, Pseudomonas aeruginosa, Salmonella species, Vibrio cholerae, and Yersinia species, represent a severe economic and health problem worldwide. Of special importance in this context is the increasing emergence and spread of multidrug-resistant bacteria. Due to the shortage of effective antibiotics for the treatment of infections caused by multidrug-resistant, pathogenic bacteria, the targeting of novel, virulence-relevant factors constitutes a promising, alternative approach. Bacteria have evolved distinct motility structures for movement across surfaces and in aqueous environments. In this review, I will focus on the bacterial flagellum, the associated chemosensory system, and the type-IV pilus as motility devices, which are crucial for bacterial pathogens to reach a preferred site of infection, facilitate biofilm formation, and adhere to surfaces or host cells. Thus, those nanomachines constitute potential targets for the development of novel anti-infectives that are urgently needed at a time of spreading antibiotic resistance. Both bacterial flagella and type-IV pili (T4P) are intricate macromolecular complexes made of dozens of different proteins and their motility function relies on the correct spatial and temporal assembly of various substructures. Specific type-III and type-IV secretion systems power the export of substrate proteins of the bacterial flagellum and type-IV pilus, respectively, and are homologous to virulence-associated type-III and type-II secretion systems. Accordingly, bacterial flagella and T4P represent attractive targets for novel antivirulence drugs interfering with synthesis, assembly, and function of these motility structures.
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