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Liu X, Tang H, Huang X, Xu M. Butyrate affects bacterial virulence: a new perspective on preventing enteric bacterial pathogen invasion. Future Microbiol 2024; 19:73-84. [PMID: 38085176 DOI: 10.2217/fmb-2023-0148] [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: 06/29/2023] [Accepted: 09/11/2023] [Indexed: 02/15/2024] Open
Abstract
Enteric bacterial pathogens are a major threat to intestinal health. With the widespread use of antibiotics, bacterial resistance has become a problem, and there is an urgent need for a new treatment to reduce dependence on antibiotics. Butyrate can control enteric bacterial pathogens by regulating the expression of their virulence genes, promoting the posttranslational modification of their proteins, maintaining an anaerobic environment, regulating the host immune system and strengthening the intestinal mucosal barrier. Here, this review describes the mechanisms by which butyrate regulates the pathogenicity of enteric bacterial pathogens from various perspectives and discusses the prospects and limitations of butyrate as a new option for the control of pathogenic bacteria.
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Affiliation(s)
- Xiucheng Liu
- Department of Gastroenterology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, 212008, China
- Department of Biochemistry & Molecular Biology, Jiangsu University School of Medicine, Zhenjiang, Jiangsu, 212013, China
| | - Hao Tang
- Department of Biochemistry & Molecular Biology, Jiangsu University School of Medicine, Zhenjiang, Jiangsu, 212013, China
| | - Xinxiang Huang
- Department of Biochemistry & Molecular Biology, Jiangsu University School of Medicine, Zhenjiang, Jiangsu, 212013, China
| | - Min Xu
- Department of Gastroenterology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, 212008, China
- Institute of Digestive Diseases, Jiangsu University, Zhenjiang, Jiangsu, 212013, China
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2
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Guan N, Shi Y, Tong H, Yang Y, Li J, Guo D, Wang X, Shan Z, Lü X, Shi C. Inhibition of Cronobacter sakazakii Biofilm Formation and Expression of Virulence Factors by Coenzyme Q 0. Foodborne Pathog Dis 2023; 20:442-452. [PMID: 37669036 DOI: 10.1089/fpd.2023.0040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/06/2023] Open
Abstract
In this study, we investigated the inhibitory effects of coenzyme Q0 (CoQ0) on biofilm formation and the expression of virulence genes by Cronobacter sakazakii. We found that the minimum inhibitory concentration of CoQ0 against C. sakazakii strains ATCC29544 and ATCC29004 was 100 μg/mL, while growth curve assays showed that subinhibitory concentrations (SICs) of CoQ0 for both strains were 6.4, 3.2, 1.6 and 0.8 μg/mL. Assays exploring the inhibition of specific biofilm formation showed that SICs of CoQ0 inhibited biofilm formation by C. sakazakii in a dose-dependent manner, which was confirmed by scanning electron microscopy and confocal laser scanning microscopy analyses. CoQ0 inhibited the swimming and swarming motility of C. sakazakii and reduced its ability to adhere to and invade HT-29 cells. In addition, CoQ0 impeded the ability of C. sakazakii to survive and replicate within RAW 264.7 cells. Finally, real-time polymerase chain reaction analysis confirmed that nine C. sakazakii genes associated with biofilm formation and virulence were downregulated in response to CoQ0 treatment. Overall, our findings suggest that CoQ0 is a promising antibiofilm agent and provide new insights for the prevention and control of infections caused by C. sakazakii.
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Affiliation(s)
- Ning Guan
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Yiqi Shi
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Haoyu Tong
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Yanpeng Yang
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Jiahui Li
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Du Guo
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Xin Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Zhongguo Shan
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Xin Lü
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Chao Shi
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
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3
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Serebrinsky-Duek K, Barra M, Danino T, Garrido D. Engineered Bacteria for Short-Chain-Fatty-Acid-Repressed Expression of Biotherapeutic Molecules. Microbiol Spectr 2023; 11:e0004923. [PMID: 36939337 PMCID: PMC10101121 DOI: 10.1128/spectrum.00049-23] [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: 01/09/2023] [Accepted: 02/20/2023] [Indexed: 03/21/2023] Open
Abstract
Short-chain fatty acids (SCFA) such as propionate and butyrate are critical metabolites produced by the gut microbiota. Microbiome dysbiosis resulting in altered SCFA profiles is associated with certain diseases, including inflammatory bowel diseases (IBD), characterized by a reduction in butyrate concentration and active intestinal inflammation. There is an increasing interest in the use of engineered bacteria as diagnostic and therapeutic tools for gut diseases. In this study, we developed genetic circuits capable of sensing SCFA concentrations to build biosensors that express a response protein (superfolder green fluorescent protein [sfGFP]) in amounts inversely proportional to the SCFA concentration. We also built biotherapeutics expressing the cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) using the same logic. The propionate biotherapeutic expressed larger amounts of mouse GM-CSF in the absence of propionate. The butyrate biotherapeutics presented the expected behavior only at the beginning of the kinetics and an accelerated response in the absence of butyrate. Overall, these genetic systems may function as complementary diagnostic tools for measuring SCFAs and as delivery vehicles for biotherapeutic molecules. IMPORTANCE Short-chain fatty acids are key molecules produced by the gut microbiome. Their concentrations are altered in certain diseases. Here, we created molecular biosensors that quantify the absence of propionate and butyrate, using logic "NOT" gates and bacterial promoters. Finally, we show that these genetic systems could be useful for the delivery of therapeutic molecules in the gut, in the absence of these acids.
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Affiliation(s)
- Kineret Serebrinsky-Duek
- Department of Chemical and Bioprocess Engineering, School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Maria Barra
- Department of Chemical and Bioprocess Engineering, School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Tal Danino
- Department of Biomedical Engineering, Columbia University, New York, New York, USA
| | - Daniel Garrido
- Department of Chemical and Bioprocess Engineering, School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
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Hamamura R, Yen H, Tobe T. SlyA regulates virulence gene expressions through activation of pchA regulatory gene in enterohemorrhagic Escherichia coli. Microbiol Immunol 2022; 66:501-509. [PMID: 36083830 DOI: 10.1111/1348-0421.13027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 09/01/2022] [Accepted: 09/05/2022] [Indexed: 11/30/2022]
Abstract
SlyA is a DNA-binding protein that alters the nucleoid complex composed of histone-like nucleoid-structuring protein (H-NS) and activates gene expression. In enterohemorrhagic Escherichia coli (EHEC), the expression of virulence genes is repressed by H-NS but is upregulated in response to environmental factors by releasing a nucleoid complex. In this study, we examined the effect of slyA deletion mutation in EHEC and discovered that the production of LEE (locus of enterocyte effacement)-encoded EspB and Tir, as well as cell adherence ability, was reduced in the mutant compared to wild type. The promoter activity of the LEE1 operon, including the regulatory gene, ler, was reduced by slyA mutation, but tac promoter-controlled expression of pchA, which is a regulatory gene of LEE1, abolished the effect. The promoter activity of pchA was downregulated by the slyA mutation. Furthermore, the coding region was required for its regulation and was bound to SlyA, which indicates the direct regulation of pchA by SlyA. However, the slyA mutation did not affect the butyrate-induced increase in pchA promoter activity. Additionally, pchA promoter activity was increased via induction of lrp, a regulatory gene for butyrate response, in the slyA mutant and, conversely, by introducing high copies of slyA into the lrp mutant. These results indicate that SlyA is a positive regulator of pchA and is independent of the Lrp regulatory system. SlyA may be involved in virulence expression in EHEC, maintaining a certain level of expression in the absence of butyrate response. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Riho Hamamura
- Department of Clinical Laboratory and Biomedical Sciences, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Hilo Yen
- Department of Clinical Laboratory and Biomedical Sciences, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Toru Tobe
- Department of Clinical Laboratory and Biomedical Sciences, Osaka University Graduate School of Medicine, Osaka, Japan
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Sun H, Wang M, Liu Y, Wu P, Yao T, Yang W, Yang Q, Yan J, Yang B. Regulation of flagellar motility and biosynthesis in enterohemorrhagic Escherichia coli O157:H7. Gut Microbes 2022; 14:2110822. [PMID: 35971812 PMCID: PMC9387321 DOI: 10.1080/19490976.2022.2110822] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
ABSTARCTEnterohemorrhagic Escherichia coli (EHEC) O157:H7 is a human pathogen that causes a variety of diseases, such as hemorrhagic colitis and lethal hemolytic uremic syndrome. Flagellum-dependent motility plays diverse roles in the pathogenesis of EHEC O157:H7, including its migration to an optimal host site, adherence and colonization, survival at the infection site, and post-infection dispersal. However, it is very expensive for cellular economy in terms of the number of genes and the energy required for flagellar biosynthesis and functioning. Furthermore, the flagellar filament bears strong antigenic properties that induce a strong host immune response. Consequently, the flagellar gene expression and biosynthesis are highly regulated to occur at the appropriate time and place by different regulatory influences. The present review focuses on the regulatory mechanisms of EHEC O157:H7 motility and flagellar biosynthesis, especially in terms of flagellar gene regulation by environmental factors, regulatory proteins, and small regulatory RNAs.
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Affiliation(s)
- Hongmin Sun
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, China
| | - Min Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, China
| | - Yutao Liu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, China
| | - Pan Wu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, China
| | - Ting Yao
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, China
| | - Wen Yang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, China
| | - Qian Yang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, China
| | - Jun Yan
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, China
| | - Bin Yang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin, China,CONTACT Bin Yang TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin300457, P. R. China
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Izquierdo M, Lopez J, Gallardo P, Vidal RM, Ossa JC, Farfan MJ. Bacteria from gut microbiota associated with diarrheal infections in children promote virulence of Shiga toxin-producing and enteroaggregative Escherichia coli pathotypes. Front Cell Infect Microbiol 2022; 12:867205. [PMID: 36017363 PMCID: PMC9396624 DOI: 10.3389/fcimb.2022.867205] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 07/07/2022] [Indexed: 11/26/2022] Open
Abstract
Background Diarrheagenic E. coli (DEC) pathogenicity relies on the interaction of bacteria with the host’s gut environment, which is regulated by the resident microbiota. Previously, we identified indicative bacterial species of gut microbiota in DEC-positive stool samples from children. Here, we evaluated the role of two indicative species, Citrobacter werkmanii (CW) and Escherichia albertii (EA), in the virulence of two DEC pathotypes, Shiga toxin-producing (STEC) and enteroaggregative (EAEC) Escherichia coli. Methods We determined the effect of supernatants obtained from CW and EA cultures on the gene expression of STEC strain 86-24 and EAEC strain 042 by RNA-seq analysis. We evaluated IL-8 secretion from T84 cells infected with these DEC strains in the presence or absence of the supernatant from EA. The effect of the supernatant from EA on the growth and adherence of STEC and EAEC to cells was also evaluated. Finally, we studied the effect of the EA supernatant on the STEC-induced inflammation mediated by the long polar fimbriae (Lpf) in T84 cells and the expression of plasmid-encoded toxin (Pet) in EAEC. Results RNA-seq analysis revealed that several virulence factors in STEC and EAEC were upregulated in the presence of supernatants from CW and EA. Interestingly, an increase in the secretion of IL-8 was observed in cells infected with STEC or EAEC in the presence of a supernatant from EA. Similar results were observed with the supernatants obtained from clinical strains of E. albertii. The supernatant from EA had no effect on the growth of STEC and EAEC, or on the ability of these DEC strains to adhere to cells. We found that Pet toxin in EAEC was upregulated in the presence of a supernatant from EA. In STEC, using mutant strains for Lpf fimbriae, our data suggested that these fimbriae might be participating in the increase in IL-8 induced by STEC in cells in the presence of a supernatant from EA. Conclusion Supernatant obtained from an indicative species of DEC-positive diarrhea could modulate gene expression in STEC and EAEC, and IL-8 secretion induced by these bacteria. These data provide new insights into the effect of gut microbiota species in the pathogenicity of STEC and EAEC.
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Affiliation(s)
- Mariana Izquierdo
- Departamento de Pediatría y Cirugía Infantil, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Joaquín Lopez
- Departamento de Pediatría y Cirugía Infantil, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Pablo Gallardo
- Departamento de Pediatría y Cirugía Infantil, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Roberto M. Vidal
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Juan C. Ossa
- Departamento de Pediatría y Cirugía Infantil, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Mauricio J. Farfan
- Departamento de Pediatría y Cirugía Infantil, Facultad de Medicina, Universidad de Chile, Santiago, Chile
- *Correspondence: Mauricio J. Farfan,
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Strain R, Stanton C, Ross RP. Effect of diet on pathogen performance in the microbiome. MICROBIOME RESEARCH REPORTS 2022; 1:13. [PMID: 38045644 PMCID: PMC10688830 DOI: 10.20517/mrr.2021.10] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 02/17/2022] [Accepted: 02/23/2022] [Indexed: 12/05/2023]
Abstract
Intricate interactions among commensal bacteria, dietary substrates and immune responses are central to defining microbiome community composition, which plays a key role in preventing enteric pathogen infection, a dynamic phenomenon referred to as colonisation resistance. However, the impact of diet on sculpting microbiota membership, and ultimately colonisation resistance has been overlooked. Furthermore, pathogens have evolved strategies to evade colonisation resistance and outcompete commensal microbiota by using unique nutrient utilisation pathways, by exploiting microbial metabolites as nutrient sources or by environmental cues to induce virulence gene expression. In this review, we will discuss the interplay between diet, microbiota and their associated metabolites, and how these can contribute to or preclude pathogen survival.
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Affiliation(s)
- Ronan Strain
- APC Microbiome Ireland, Biosciences Institute, University College Cork, Cork T12 YT20, Ireland
- Teagasc Food Research Centre, Moorepark, Fermoy, Co. Cork P61 C996, Ireland
| | - Catherine Stanton
- APC Microbiome Ireland, Biosciences Institute, University College Cork, Cork T12 YT20, Ireland
- Teagasc Food Research Centre, Moorepark, Fermoy, Co. Cork P61 C996, Ireland
| | - R. Paul Ross
- APC Microbiome Ireland, Biosciences Institute, University College Cork, Cork T12 YT20, Ireland
- School of Microbiology, University College Cork, College Road, Cork T12 K8AF, Ireland
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George S, Aguilera X, Gallardo P, Farfán M, Lucero Y, Torres JP, Vidal R, O'Ryan M. Bacterial Gut Microbiota and Infections During Early Childhood. Front Microbiol 2022; 12:793050. [PMID: 35069488 PMCID: PMC8767011 DOI: 10.3389/fmicb.2021.793050] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 12/10/2021] [Indexed: 12/12/2022] Open
Abstract
Gut microbiota composition during the first years of life is variable, dynamic and influenced by both prenatal and postnatal factors, such as maternal antibiotics administered during labor, delivery mode, maternal diet, breastfeeding, and/or antibiotic consumption during infancy. Furthermore, the microbiota displays bidirectional interactions with infectious agents, either through direct microbiota-microorganism interactions or indirectly through various stimuli of the host immune system. Here we review these interactions during childhood until 5 years of life, focusing on bacterial microbiota, the most common gastrointestinal and respiratory infections and two well characterized gastrointestinal diseases related to dysbiosis (necrotizing enterocolitis and Clostridioides difficile infection). To date, most peer-reviewed studies on the bacterial microbiota in childhood have been cross-sectional and have reported patterns of gut dysbiosis during infections as compared to healthy controls; prospective studies suggest that most children progressively return to a "healthy microbiota status" following infection. Animal models and/or studies focusing on specific preventive and therapeutic interventions, such as probiotic administration and fecal transplantation, support the role of the bacterial gut microbiota in modulating both enteric and respiratory infections. A more in depth understanding of the mechanisms involved in the establishment and maintenance of the early bacterial microbiota, focusing on specific components of the microbiota-immunity-infectious agent axis is necessary in order to better define potential preventive or therapeutic tools against significant infections in children.
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Affiliation(s)
- Sergio George
- Host-Pathogen Interaction Laboratory, Microbiology and Mycology Program, ICBM, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Ximena Aguilera
- School of Medicine, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Pablo Gallardo
- Department of Pediatrics and Pediatric Surgery, Dr. Luis Calvo Mackenna Hospital, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Mauricio Farfán
- Department of Pediatrics and Pediatric Surgery, Dr. Luis Calvo Mackenna Hospital, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Yalda Lucero
- Host-Pathogen Interaction Laboratory, Microbiology and Mycology Program, ICBM, Faculty of Medicine, University of Chile, Santiago, Chile.,Department of Pediatrics and Pediatric Surgery, Dr. Roberto del Río Hospital, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Juan Pablo Torres
- Host-Pathogen Interaction Laboratory, Microbiology and Mycology Program, ICBM, Faculty of Medicine, University of Chile, Santiago, Chile.,Department of Pediatrics and Pediatric Surgery, Dr. Luis Calvo Mackenna Hospital, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Roberto Vidal
- Microbiology and Mycology Program, ICBM, Faculty of Medicine, University of Chile, Santiago, Chile.,Millennium Institute on Immunology and Immunotherapy, Faculty of Medicine, University of Chile, Santiago, Chile.,ANID - Millennium Science Initiative Program - Millennium Nucleus in the Biology of Intestinal Microbiota, Santiago, Chile
| | - Miguel O'Ryan
- Host-Pathogen Interaction Laboratory, Microbiology and Mycology Program, ICBM, Faculty of Medicine, University of Chile, Santiago, Chile.,Millennium Institute on Immunology and Immunotherapy, Faculty of Medicine, University of Chile, Santiago, Chile
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9
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AB 5 Enterotoxin-Mediated Pathogenesis: Perspectives Gleaned from Shiga Toxins. Toxins (Basel) 2022; 14:toxins14010062. [PMID: 35051039 PMCID: PMC8779504 DOI: 10.3390/toxins14010062] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 01/12/2022] [Accepted: 01/12/2022] [Indexed: 02/01/2023] Open
Abstract
Foodborne diseases affect an estimated 600 million people worldwide annually, with the majority of these illnesses caused by Norovirus, Vibrio, Listeria, Campylobacter, Salmonella, and Escherichia coli. To elicit infections in humans, bacterial pathogens express a combination of virulence factors and toxins. AB5 toxins are an example of such toxins that can cause various clinical manifestations, including dehydration, diarrhea, kidney damage, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). Treatment of most bacterial foodborne illnesses consists of fluid replacement and antibiotics. However, antibiotics are not recommended for infections caused by Shiga toxin-producing E. coli (STEC) because of the increased risk of HUS development, although there are conflicting views and results in this regard. Lack of effective treatment strategies for STEC infections pose a public health threat during outbreaks; therefore, the debate on antibiotic use for STEC infections could be further explored, along with investigations into antibiotic alternatives. The overall goal of this review is to provide a succinct summary on the mechanisms of action and the pathogenesis of AB5 and related toxins, as expressed by bacterial foodborne pathogens, with a primary focus on Shiga toxins (Stx). The role of Stx in human STEC disease, detection methodologies, and available treatment options are also briefly discussed.
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10
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Liu B, Qian C, Wu P, Li X, Liu Y, Mu H, Huang M, Zhang Y, Jia T, Wang Y, Wang L, Zhang X, Huang D, Yang B, Feng L, Wang L. Attachment of Enterohemorrhagic Escherichia coli to Host Cells Reduces O Antigen Chain Length at the Infection Site That Promotes Infection. mBio 2021; 12:e0269221. [PMID: 34903041 PMCID: PMC8669466 DOI: 10.1128/mbio.02692-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Accepted: 11/15/2021] [Indexed: 11/20/2022] Open
Abstract
Many enteropathogenic bacteria express a needle-like type III secretion system (T3SS) that translocates effectors into host cells promoting infection. O antigen (OAg) constitutes the outer layer of Gram-negative bacteria protecting bacteria from host immune responses. Shigella constitutively shortens the OAg molecule in its three-dimensional conformation by glucosylation, leading to enhanced T3SS function. However, whether and how other enteropathogenic bacteria shorten the OAg molecule that probably facilitates infection remain unknown. For the first time, we report a smart mechanism by which enterohemorrhagic Escherichia coli specifically reduces the size of the OAg molecule at the infection site upon sensing mechanical signals of intestinal epithelial cell attachment via the membrane protein YgjI. YgjI represses expression of the OAg chain length regulator gene fepE via the global regulator H-NS, leading to shortened OAg chains and injection of more T3SS effectors into host cells. However, bacteria express long-chain OAg in the intestinal lumen benefiting their survival. Animal experiments show that blocking this regulatory pathway significantly attenuates bacterial virulence. This finding enhances our understanding of interactions between the surfaces of bacterial and host cells and the way this interaction enhances bacterial pathogenesis. IMPORTANCE Little is known about the regulation of cell wall structure of enteropathogenic bacteria within the host. Here, we report that enterohemorrhagic Escherichia coli regulates its cell wall structure during the infection process, which balances its survival in the intestinal lumen and infection of intestinal epithelial cells. In the intestinal lumen, bacteria express long-chain OAg, which is located in the outer part of the cell wall, leading to enhanced resistance to antimicrobial peptides. However, upon epithelial cell attachment, bacteria sense this mechanical signal via a membrane protein and reduce the OAg chain length, resulting in enhanced injection into epithelial cells of T3SS effectors that mediate host cell infection. Similar regulation mechanisms of cell wall structure in response to host cell attachment may be widespread in pathogenic bacteria and closely related with bacterial pathogenesis.
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Affiliation(s)
- Bin Liu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
- The Institute of Translational Medicine Research, Tianjin Union Medical Center, Nankai University Affiliated Hospital, Nankai University, Tianjin, People’s Republic of China
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People’s Republic of China
- Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, People’s Republic of China
| | - Chengqian Qian
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Pan Wu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Xiaodan Li
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Yutao Liu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Huiqian Mu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Min Huang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Yang Zhang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Tianyuan Jia
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Yuanyuan Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Lu Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Xiao Zhang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Di Huang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Bin Yang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
| | - Lu Feng
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People’s Republic of China
- Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, People’s Republic of China
| | - Lei Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, People’s Republic of China
- The Institute of Translational Medicine Research, Tianjin Union Medical Center, Nankai University Affiliated Hospital, Nankai University, Tianjin, People’s Republic of China
- The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, People’s Republic of China
- Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, People’s Republic of China
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin, People’s Republic of China
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11
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Pettersen VK, Antunes LCM, Dufour A, Arrieta MC. Inferring early-life host and microbiome functions by mass spectrometry-based metaproteomics and metabolomics. Comput Struct Biotechnol J 2021; 20:274-286. [PMID: 35024099 PMCID: PMC8718658 DOI: 10.1016/j.csbj.2021.12.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 12/08/2021] [Accepted: 12/08/2021] [Indexed: 12/17/2022] Open
Abstract
Humans have a long-standing coexistence with microorganisms. In particular, the microbial community that populates the human gastrointestinal tract has emerged as a critical player in governing human health and disease. DNA and RNA sequencing techniques that map taxonomical composition and genomic potential of the gut community have become invaluable for microbiome research. However, deriving a biochemical understanding of how activities of the gut microbiome shape host development and physiology requires an expanded experimental design that goes beyond these approaches. In this review, we explore advances in high-throughput techniques based on liquid chromatography-mass spectrometry. These omics methods for the identification of proteins and metabolites have enabled direct characterisation of gut microbiome functions and the crosstalk with the host. We discuss current metaproteomics and metabolomics workflows for producing functional profiles, the existing methodological challenges and limitations, and recent studies utilising these techniques with a special focus on early life gut microbiome.
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Affiliation(s)
- Veronika Kuchařová Pettersen
- Research Group for Host-Microbe Interactions, Department of Medical Biology, UiT The Arctic University of Norway, Tromsø, Norway
- Pediatric Research Group, Department of Clinical Medicine, UiT The Arctic University of Norway, Tromsø, Norway
- Centre for New Antibacterial Strategies, UiT The Arctic University of Norway, Tromsø, Norway
| | - Luis Caetano Martha Antunes
- Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, RJ, Brazil
- National Institute of Science and Technology of Innovation on Diseases of Neglected Populations, Center for Technological Development in Health, Oswaldo Cruz Foundation, Rio de Janeiro, RJ, Brazil
| | - Antoine Dufour
- Department of Physiology & Pharmacology, University of Calgary, Calgary, Canada
| | - Marie-Claire Arrieta
- Department of Physiology & Pharmacology, University of Calgary, Calgary, Canada
- Department of Pediatrics, University of Calgary, Calgary, AB, Canada
- International Microbiome Centre, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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12
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Mirzaei R, Dehkhodaie E, Bouzari B, Rahimi M, Gholestani A, Hosseini-Fard SR, Keyvani H, Teimoori A, Karampoor S. Dual role of microbiota-derived short-chain fatty acids on host and pathogen. Biomed Pharmacother 2021; 145:112352. [PMID: 34840032 DOI: 10.1016/j.biopha.2021.112352] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 10/15/2021] [Accepted: 10/19/2021] [Indexed: 12/12/2022] Open
Abstract
A growing body of documents shows microbiota produce metabolites such as short-chain fatty acids (SCFAs) as crucial executors of diet-based microbial influence the host and bacterial pathogens. The production of SCFAs depends on the metabolic activity of intestinal microflora and is also affected by dietary changes. SCFAs play important roles in maintaining colonic health as an energy source, as a regulator of gene expression and cell differentiation, and as an anti-inflammatory agent. Additionally, the regulated expression of virulence genes is critical for successful infection by an intestinal pathogen. Bacteria rely on sensing environmental signals to find preferable niches and reach the infectious state. This review will present data supporting the diverse functional roles of microbiota-derived butyrate, propionate, and acetate on host cellular activities such as immune modulation, energy metabolism, nervous system, inflammation, cellular differentiation, and anti-tumor effects, among others. On the other hand, we will discuss and summarize data about the role of these SCFAs on the virulence factor of bacterial pathogens. In this regard, receptors and signaling routes for SCFAs metabolites in host and pathogens will be introduced.
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Affiliation(s)
- Rasoul Mirzaei
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran; Venom and Biotherapeutics Molecules Lab, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran.
| | - Elahe Dehkhodaie
- Department of Biology, Science and Research Branch, Islamic Azad University Tehran, Iran
| | - Behnaz Bouzari
- Department of Pathology, Firouzgar Hospital, Iran University of Medical Sciences, Tehran, Iran
| | - Mandana Rahimi
- Department of Pathology, School of Medicine, Hasheminejad Kidney Center, Iran University of Medical Sciences, Tehran, Iran
| | - Abolfazl Gholestani
- Department of Biochemistry, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyed Reza Hosseini-Fard
- Department of Biochemistry, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Keyvani
- Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
| | - Ali Teimoori
- Department of Virology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
| | - Sajad Karampoor
- Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
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13
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The Short-Chain Fatty Acids Propionate and Butyrate Augment Adherent-Invasive Escherichia coli Virulence but Repress Inflammation in a Human Intestinal Enteroid Model of Infection. Microbiol Spectr 2021; 9:e0136921. [PMID: 34612688 PMCID: PMC8510176 DOI: 10.1128/spectrum.01369-21] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Short-chain fatty acids (SCFAs), which consist of six or fewer carbons, are fermentation products of the bacterial community that inhabits the intestine. Due to an immunosuppressive effect on intestinal tissue, they have been touted as a therapeutic for inflammatory conditions of the bowel. Here, we study the impact of acetate, propionate, and butyrate, the three most abundant SCFAs in the intestine, on gene expression in the intestinal pathobiont adherent-invasive Escherichia coli. We pair this with adherence, invasion, and inflammation in Caco-2 and human intestinal enteroid (HIE)-derived monolayer models of the intestinal epithelium. We report that propionate and butyrate upregulate transcription of adherent-invasive Escherichia coli (AIEC) flagellar synthesis genes and decrease expression of capsule assembly and transport genes. These changes are predicted to augment AIEC invasiveness. In fact, SCFA supplementation increases AIEC adherence to and invasion of the Caco-2 monolayer but has no effect on these parameters in the HIE model. We attribute this to the anti-inflammatory effect of propionate and butyrate on HIEs but not on Caco-2 cells. We conclude that the potential of SCFAs to increase the virulence of intestinal pathogens should be considered in their use as anti-inflammatory agents. IMPORTANCE The human terminal ileum and colon are colonized by a community of microbes known as the microbiota. Short-chain fatty acids (SCFAs) excreted by bacterial members of the microbiota define the intestinal environment. These constitute an important line of communication within the microbiota and between the microbiota and the host epithelium. In inflammatory conditions of the bowel, SCFAs are often low and there is a preponderance of a conditionally virulent bacterium termed adherent-invasive Escherichia coli (AIEC). A connection between SCFA abundance and AIEC has been suggested. Here, we study AIEC in monoculture and in coculture with human intestinal enteroid-derived monolayers and show that the SCFAs propionate and butyrate increase expression of AIEC virulence genes while concurrently bolstering the intestinal epithelial barrier and reducing intestinal inflammation. While these SCFAs have been promoted as a therapy for inflammatory bowel conditions, our findings demonstrate that their effect on bacterial virulence must be considered.
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14
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Segura A, Bertin Y, Durand A, Benbakkar M, Forano E. Transcriptional analysis reveals specific niche factors and response to environmental stresses of enterohemorrhagic Escherichia coli O157:H7 in bovine digestive contents. BMC Microbiol 2021; 21:284. [PMID: 34663220 PMCID: PMC8524897 DOI: 10.1186/s12866-021-02343-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 09/24/2021] [Indexed: 02/08/2023] Open
Abstract
Background Enterohemorrhagic Escherichia coli (EHEC) are responsible for severe diseases in humans, and the ruminant digestive tract is considered as their main reservoir. Their excretion in bovine feces leads to the contamination of foods and the environment. Thus, providing knowledge of processes used by EHEC to survive and/or develop all along the bovine gut represents a major step for strategies implementation. Results We compared the transcriptome of the reference EHEC strain EDL933 incubated in vitro in triplicate samples in sterile bovine rumen, small intestine and rectum contents with that of the strain grown in an artificial medium using RNA-sequencing (RNA-seq), focusing on genes involved in stress response, adhesion systems including the LEE, iron uptake, motility and chemotaxis. We also compared expression of these genes in one digestive content relative to the others. In addition, we quantified short chain fatty acids and metal ions present in the three digestive contents. RNA-seq data first highlighted response of EHEC EDL933 to unfavorable physiochemical conditions encountered during its transit through the bovine gut lumen. Seventy-eight genes involved in stress responses including drug export, oxidative stress and acid resistance/pH adaptation were over-expressed in all the digestive contents compared with artificial medium. However, differences in stress fitness gene expression were observed depending on the digestive segment, suggesting that these differences were due to distinct physiochemical conditions in the bovine digestive contents. EHEC activated genes encoding three toxin/antitoxin systems in rumen content and many gene clusters involved in motility and chemotaxis in rectum contents. Genes involved in iron uptake and utilization were mostly down-regulated in all digestive contents compared with artificial medium, but feo genes were over-expressed in rumen and small intestine compared with rectum. The five LEE operons were more expressed in rectum than in rumen content, and LEE1 was also more expressed in rectum than in small intestine content. Conclusion Our results highlight various strategies that EHEC may implement to survive in the gastrointestinal environment of cattle. These data could also help defining new targets to limit EHEC O157:H7 carriage and shedding by cattle. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-021-02343-7.
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Affiliation(s)
- Audrey Segura
- Université Clermont Auvergne, INRAE, MEDIS 0454, F-63000, Clermont-Ferrand, France
| | - Yolande Bertin
- Université Clermont Auvergne, INRAE, MEDIS 0454, F-63000, Clermont-Ferrand, France
| | - Alexandra Durand
- Université Clermont Auvergne, INRAE, MEDIS 0454, F-63000, Clermont-Ferrand, France
| | - Mhammed Benbakkar
- Université Clermont Auvergne, CNRS, IRD, OPGC, Laboratoire Magmas et Volcans, F-63000, Clermont-Ferrand, France
| | - Evelyne Forano
- Université Clermont Auvergne, INRAE, MEDIS 0454, F-63000, Clermont-Ferrand, France.
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15
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Machado MG, Sencio V, Trottein F. Short-Chain Fatty Acids as a Potential Treatment for Infections: a Closer Look at the Lungs. Infect Immun 2021; 89:e0018821. [PMID: 34097474 PMCID: PMC8370681 DOI: 10.1128/iai.00188-21] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Short-chain fatty acids (SCFAs) are the main metabolites produced by the gut microbiota via the fermentation of complex carbohydrates and fibers. Evidence suggests that SCFAs play a role in the control of infections through direct action both on microorganisms and on host signaling. This review summarizes the main microbicidal effects of SCFAs and discusses studies highlighting the effect of SCFAs in the virulence and viability of microorganisms. We also describe the diverse and complex modes of action of the SCFAs on the immune system in the face of infections with a specific focus on bacterial and viral respiratory infections. A growing body of evidence suggests that SCFAs protect against lung infections. Finally, we present potential strategies that may be leveraged to exploit the biological properties of SCFAs for increasing effectiveness and optimizing patient benefits.
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Affiliation(s)
- Marina Gomes Machado
- Centre d’Infection et d’Immunité de Lille, INSERM U1019, CNRS UMR 9017, University of Lille, CHU Lille, Institut Pasteur de Lille, Lille, France
- Laboratory of Immunopharmacology, Department of Biochemistry and Immunology, ICB, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Valentin Sencio
- Centre d’Infection et d’Immunité de Lille, INSERM U1019, CNRS UMR 9017, University of Lille, CHU Lille, Institut Pasteur de Lille, Lille, France
| | - François Trottein
- Centre d’Infection et d’Immunité de Lille, INSERM U1019, CNRS UMR 9017, University of Lille, CHU Lille, Institut Pasteur de Lille, Lille, France
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16
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Ziegler CA, Freddolino PL. The leucine-responsive regulatory proteins/feast-famine regulatory proteins: an ancient and complex class of transcriptional regulators in bacteria and archaea. Crit Rev Biochem Mol Biol 2021; 56:373-400. [PMID: 34151666 DOI: 10.1080/10409238.2021.1925215] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Since the discovery of the Escherichia coli leucine-responsive regulatory protein (Lrp) almost 50 years ago, hundreds of Lrp homologs have been discovered, occurring in 45% of sequenced bacteria and almost all sequenced archaea. Lrp-like proteins are often referred to as the feast/famine regulatory proteins (FFRPs), reflecting their common regulatory roles. Acting as either global or local transcriptional regulators, FFRPs detect the environmental nutritional status by sensing small effector molecules (usually amino acids) and regulate the expression of genes involved in metabolism, virulence, motility, nutrient transport, stress tolerance, and antibiotic resistance to implement appropriate behaviors for the specific ecological niche of each organism. Despite FFRPs' complexity, a significant role in gene regulation, and prevalence throughout prokaryotes, the last comprehensive review on this family of proteins was published about a decade ago. In this review, we integrate recent notable findings regarding E. coli Lrp and other FFRPs across bacteria and archaea with previous observations to synthesize a more complete view on the mechanistic details and biological roles of this ancient class of transcription factors.
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Affiliation(s)
- Christine A Ziegler
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Peter L Freddolino
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA.,Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, USA
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17
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Machado Ribeiro TR, Salgaço MK, Adorno MAT, da Silva MA, Piazza RMF, Sivieri K, Moreira CG. Human microbiota modulation via QseC sensor kinase mediated in the Escherichia coli O104:H4 outbreak strain infection in microbiome model. BMC Microbiol 2021; 21:163. [PMID: 34078285 PMCID: PMC8170955 DOI: 10.1186/s12866-021-02220-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 05/06/2021] [Indexed: 01/01/2023] Open
Abstract
Background The intestinal microbiota plays a crucial role in human health, adjusting its composition and the microbial metabolites protects the gut against invading microorganisms. Enteroaggregative E. coli (EAEC) is an important diarrheagenic pathogen, which may cause acute or persistent diarrhea (≥14 days). The outbreak strain has the potent Shiga toxin, forms a dense biofilm and communicate via QseBC two-component system regulating the expression of many important virulence factors. Results Herein, we investigated the QseC histidine sensor kinase role in the microbiota shift during O104:H4 C227–11 infection in the colonic model SHIME® (Simulator of the Human Intestinal Microbial Ecosystem) and in vivo mice model. The microbiota imbalance caused by C227–11 infection affected ỿ-Proteobacteria and Lactobacillus spp. predominance, with direct alteration in intestinal metabolites driven by microbiota change, such as Short-chain fatty acids (SCFA). However, in the absence of QseC sensor kinase, the microbiota recovery was delayed on day 3 p.i., with change in the intestinal production of SCFA, like an increase in acetate production. The higher predominance of Lactobacillus spp. in the microbiota and significant augmented qseC gene expression levels were also observed during C227–11 mice infection upon intestinal depletion. Novel insights during pathogenic bacteria infection with the intestinal microbiota were observed. The QseC kinase sensor seems to have a role in the microbiota shift during the infectious process by Shiga toxin-producing EAEC C227–11. Conclusions The QseC role in C227–11 infection helps to unravel the intestine microbiota modulation and its metabolites during SHIME® and in vivo models, besides they contribute to elucidate bacterial intestinal pathogenesis and the microbiota relationships. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-021-02220-3.
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Affiliation(s)
- Tamara Renata Machado Ribeiro
- Department of Biological Sciences, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, SP, Brazil
| | - Mateus Kawata Salgaço
- Department of Food and Nutrition, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, SP, Brazil
| | - Maria Angela Tallarico Adorno
- Department of Hydraulics and Sanitation, School of Engineering of São Carlos, University of São Paulo (USP), São Carlos, SP, Brazil
| | | | | | - Katia Sivieri
- Department of Food and Nutrition, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, SP, Brazil
| | - Cristiano Gallina Moreira
- Department of Biological Sciences, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, SP, Brazil.
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18
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Walker AC, Bhargava R, Vaziriyan-Sani AS, Pourciau C, Donahue ET, Dove AS, Gebhardt MJ, Ellward GL, Romeo T, Czyż DM. Colonization of the Caenorhabditis elegans gut with human enteric bacterial pathogens leads to proteostasis disruption that is rescued by butyrate. PLoS Pathog 2021; 17:e1009510. [PMID: 33956916 PMCID: PMC8101752 DOI: 10.1371/journal.ppat.1009510] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 03/29/2021] [Indexed: 12/12/2022] Open
Abstract
Protein conformational diseases are characterized by misfolding and toxic aggregation of metastable proteins, often culminating in neurodegeneration. Enteric bacteria influence the pathogenesis of neurodegenerative diseases; however, the complexity of the human microbiome hinders our understanding of how individual microbes influence these diseases. Disruption of host protein homeostasis, or proteostasis, affects the onset and progression of these diseases. To investigate the effect of bacteria on host proteostasis, we used Caenorhabditis elegans expressing tissue-specific polyglutamine reporters that detect changes in the protein folding environment. We found that colonization of the C. elegans gut with enteric bacterial pathogens disrupted proteostasis in the intestine, muscle, neurons, and the gonad, while the presence of bacteria that conditionally synthesize butyrate, a molecule previously shown to be beneficial in neurodegenerative disease models, suppressed aggregation and the associated proteotoxicity. Co-colonization with this butyrogenic strain suppressed bacteria-induced protein aggregation, emphasizing the importance of microbial interaction and its impact on host proteostasis. Further experiments demonstrated that the beneficial effect of butyrate depended on the bacteria that colonized the gut and that this protective effect required SKN-1/Nrf2 and DAF-16/FOXO transcription factors. We also found that bacteria-derived protein aggregates contribute to the observed disruption of host proteostasis. Together, these results reveal the significance of enteric infection and gut dysbiosis on the pathogenesis of protein conformational diseases and demonstrate the potential of using butyrate-producing microbes as a preventative and treatment strategy for neurodegenerative disease.
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Affiliation(s)
- Alyssa C. Walker
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Rohan Bhargava
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Alfonso S. Vaziriyan-Sani
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Christine Pourciau
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Emily T. Donahue
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Autumn S. Dove
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Michael J. Gebhardt
- Division of Infectious Diseases, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Garrett L. Ellward
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Tony Romeo
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Daniel M. Czyż
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
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19
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Rauf A, Khalil AA, Rahman UU, Khalid A, Naz S, Shariati MA, Rebezov M, Urtecho EZ, de Albuquerque RDDG, Anwar S, Alamri A, Saini RK, Rengasamy KRR. Recent advances in the therapeutic application of short-chain fatty acids (SCFAs): An updated review. Crit Rev Food Sci Nutr 2021; 62:6034-6054. [PMID: 33703960 DOI: 10.1080/10408398.2021.1895064] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Over the past decade, the gut microbiota has emerged as an important frontier in understanding the human body's homeostasis and the development of diseases. Gut flora in human beings regulates various metabolic functionalities, including enzymes, amino acid synthesis, bio-transformation of bile acid, fermentation of non-digestible carbohydrates (NDCs), generation of indoles and polyamines (PAs), and production of short-chain fatty acids (SCFAs). Among all the metabolites produced by gut microbiota, SCFAs, the final product of fermentation of dietary fibers by gut microbiota, receive lots of attention from scientists due to their pharmacological and physiological characteristics. However, the molecular mechanisms underlying the role of SCFAs in the interaction between diet, gut microbiota, and host energy metabolism is still needed in-depth research. This review highlights the recent biotechnological advances in applying SCFAs as important metabolites to treat various diseases and maintain colonic health.
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Affiliation(s)
- Abdur Rauf
- Department of Chemistry, University of Swabi, Swabi, Anbar, Khyber Pakhtunkhwa (KP), Pakistan
| | - Anees Ahmed Khalil
- University Institute of Diet and Nutritional Sciences, Faculty of Allied Health Sciences, The University of Lahore, Pakistan
| | - Ubaid-Ur- Rahman
- School of Food and Agricultural Sciences, University of Management and Technology, Lahore, Pakistan
| | - Ahood Khalid
- University Institute of Diet and Nutritional Sciences, Faculty of Allied Health Sciences, The University of Lahore, Pakistan
| | - Saima Naz
- Deaprtment of Biotechnology, Woman University Mardan, Mardan, Khyber Pakhtunkhwa (KP), Pakistan
| | - Mohammad Ali Shariati
- K.G. Razumovsky, Moscow State University of Technologies and Management (the First Cossack University), Moscow, Russian
| | - Maksim Rebezov
- V.M. Gorbatov Federal Research Center for Food Systems of Russian Academy of Sciences, Moscow, Russian.,Prokhorov General Physics Institute of the, Russian Academy of Science, Moscow, Russian
| | | | | | - Sirajudheen Anwar
- Department of Pharmacology & Toxicology, College of Pharmacy, University of Hail, Hail, KSA
| | - Abdulwahab Alamri
- Department of Pharmacology & Toxicology, College of Pharmacy, University of Hail, Hail, KSA
| | | | - Kannan R R Rengasamy
- Indigenous Knowledge Systems Centre, Faculty of Natural and Agricultural Sciences, North-West University, Mmabatho, North West Province, South Africa
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20
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Mapping the Transcriptional and Fitness Landscapes of a Pathogenic E. coli Strain: The Effects of Organic Acid Stress under Aerobic and Anaerobic Conditions. Genes (Basel) 2020; 12:genes12010053. [PMID: 33396416 PMCID: PMC7824302 DOI: 10.3390/genes12010053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/22/2020] [Accepted: 12/29/2020] [Indexed: 12/31/2022] Open
Abstract
Several methods are available to probe cellular responses to external stresses at the whole genome level. RNAseq can be used to measure changes in expression of all genes following exposure to stress, but gives no information about the contribution of these genes to an organism’s ability to survive the stress. The relative contribution of each non-essential gene in the genome to the fitness of the organism under stress can be obtained using methods that use sequencing to estimate the frequencies of members of a dense transposon library grown under different conditions, for example by transposon-directed insertion sequencing (TraDIS). These two methods thus probe different aspects of the underlying biology of the organism. We were interested to determine the extent to which the data from these two methods converge on related genes and pathways. To do this, we looked at a combination of biologically meaningful stresses. The human gut contains different organic short-chain fatty acids (SCFAs) produced by fermentation of carbon compounds, and Escherichia coli is exposed to these in its passage through the gut. Their effect is likely to depend on both the ambient pH and the level of oxygen present. We, therefore, generated RNAseq and TraDIS data on a uropathogenic E. coli strain grown at either pH 7 or pH 5.5 in the presence or absence of three SCFAs (acetic, propionic and butyric), either aerobically or anaerobically. Our analysis identifies both known and novel pathways as being likely to be important under these conditions. There is no simple correlation between gene expression and fitness, but we found a significant overlap in KEGG pathways that are predicted to be enriched following analysis of the data from the two methods, and the majority of these showed a fitness signature that would be predicted from the gene expression data, assuming expression to be adaptive. Genes which are not in the E. coli core genome were found to be particularly likely to show a positive correlation between level of expression and contribution to fitness.
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21
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Andreozzi E, Uhlich GA. PchE Regulation of Escherichia coli O157:H7 Flagella, Controlling the Transition to Host Cell Attachment. Int J Mol Sci 2020; 21:ijms21134592. [PMID: 32605187 PMCID: PMC7369912 DOI: 10.3390/ijms21134592] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 06/24/2020] [Accepted: 06/26/2020] [Indexed: 11/16/2022] Open
Abstract
Shiga toxins and intimate adhesion controlled by the locus of enterocyte effacement are major enterohemorrhagic Escherichia coli (EHEC) virulence factors. Curli fimbriae also contribute to cell adhesion and are essential biofilm components. The transcriptional regulator PchE represses the expression of curli and their adhesion to HEp-2 cells. Past studies indicate that pchE also represses additional adhesins that contribute to HEp-2 cell attachment. In this study, we tested for pchE regulation of several tissue adhesins and their regulators. Three adhesin-encoding genes (eae, lpfA1, fliC) and four master regulators (csgD, stpA, ler, flhDC) were controlled by pchE. pchE over-expression strongly up-regulated fliC but the marked flagella induction reduced the attachment of O157:H7 clinical isolate PA20 to HEp-2 cells, indicating that flagella were blocking cell attachments rather than functioning as an adhesin. Chemotaxis, motor, structural, and regulatory genes in the flagellar operons were all increased by pchE expression, as was PA20 motility. This study identifies new members in the pchE regulon and shows that pchE stimulates flagellar motility while repressing cell adhesion, likely to support EHEC movement to the intestinal surface early in infection. However, induced or inappropriate pchE-dependent flagellar expression could block cell attachments later during disease progression.
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22
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Chen M, Fan B, Liu S, Imam KMSU, Xie Y, Wen B, Xin F. The in vitro Effect of Fibers With Different Degrees of Polymerization on Human Gut Bacteria. Front Microbiol 2020; 11:819. [PMID: 32477290 PMCID: PMC7242623 DOI: 10.3389/fmicb.2020.00819] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 04/06/2020] [Indexed: 12/20/2022] Open
Abstract
Human gut bacteria contribute significantly to human health and several studies have evaluated the effects of dietary fibers on human gut bacterial ecology. However, the relationship between different degrees of fiber polymerization and human gut bacteria is unknown. Here, we analyzed three fiber substrates with different degrees of polymerization, namely carboxymethylcellulose, β-glucans, and galactooligosaccharides. To probe the in vitro influence of the degree of polymerization of the fiber on human gut bacteria, we measured the pH, air pressure, and short-chain fatty acid content of fecal fermentation supplemented with these fiber substrates, and sequenced the 16S ribosomal RNA genes of the microbial community in the fiber-treated fermentations. The butyric acid concentration was shown to decline with decreasing degree of polymerization of the fiber. Illumina Miseq sequencing indicated that the degree of polymerization might have an influence on human gut microbial diversity and abundance. Principal coordinate analysis unveiled a relationship between the degree of fiber polymerization and the gut bacterial community. Specific microbiota operational taxonomic units (OTUs) within the genera Escherichia-Shigella, Fusobacterium, and Dorea were proportional to the degree of fiber significantly, whereas OTUs within the genera Bifidobacterium, Streptococcus, and Lactobacillus were inversely correlated with the degree of polymerization. Correlation analysis between the fiber degree of polymerization and gut bacteria may demonstrate the effect of fibers on gut microbiota, and subsequently, on human health.
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Affiliation(s)
- Miao Chen
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Bei Fan
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China.,Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs, Beijing, China
| | - Shujun Liu
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Khandaker Md Sharif Uddin Imam
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yingying Xie
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Boting Wen
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fengjiao Xin
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
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Campylobacter jejuni BumSR directs a response to butyrate via sensor phosphatase activity to impact transcription and colonization. Proc Natl Acad Sci U S A 2020; 117:11715-11726. [PMID: 32398371 DOI: 10.1073/pnas.1922719117] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Campylobacter jejuni monitors intestinal metabolites produced by the host and microbiota to initiate intestinal colonization of avian and animal hosts for commensalism and infection of humans for diarrheal disease. We previously discovered that C. jejuni has the capacity to spatially discern different intestinal regions by sensing lactate and the short-chain fatty acids acetate and butyrate and then alter transcription of colonization factors appropriately for in vivo growth. In this study, we identified the C. jejuni butyrate-modulated regulon and discovered that the BumSR two-component signal transduction system (TCS) directs a response to butyrate by identifying mutants in a genetic screen defective for butyrate-modulated transcription. The BumSR TCS, which is important for infection of humans and optimal colonization of avian hosts, senses butyrate likely by indirect means to alter transcription of genes encoding important colonization determinants. Unlike many canonical TCSs, the predicted cytoplasmic sensor kinase BumS lacked in vitro autokinase activity, which would normally lead to phosphorylation of the cognate BumR response regulator. Instead, BumS has likely evolved mutations to naturally function as a phosphatase whose activity is influenced by exogenous butyrate to control the level of endogenous phosphorylation of BumR and its ability to alter transcription of target genes. To our knowledge, the BumSR TCS is the only bacterial signal transduction system identified so far that mediates responses to the microbiota-generated intestinal metabolite butyrate, an important factor for host intestinal health and homeostasis. Our findings suggest that butyrate sensing by this system is vital for C. jejuni colonization of multiple hosts.
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Immune-Microbiota Interplay and Colonization Resistance in Infection. Mol Cell 2020; 78:597-613. [DOI: 10.1016/j.molcel.2020.03.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 02/12/2020] [Accepted: 03/02/2020] [Indexed: 02/07/2023]
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Variations in microbiota composition of laboratory mice influence Citrobacter rodentium infection via variable short-chain fatty acid production. PLoS Pathog 2020; 16:e1008448. [PMID: 32208465 PMCID: PMC7141690 DOI: 10.1371/journal.ppat.1008448] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 04/08/2020] [Accepted: 03/01/2020] [Indexed: 01/08/2023] Open
Abstract
The composition of the intestinal microbiota influences the outcome of enteric infections in human and mice. However, the role of specific members and their metabolites contributing to disease severity is largely unknown. Using isogenic mouse lines harboring distinct microbiota communities, we observed highly variable disease kinetics of enteric Citrobacter rodentium colonization after infection. Transfer of communities from susceptible and resistant mice into germ-free mice verified that the varying susceptibilities are determined by microbiota composition. The strongest differences in colonization were observed in the cecum and could be maintained in vitro by coculturing cecal bacteria with C. rodentium. Cohousing of animals as well as the transfer of cultivable bacteria from resistant to susceptible mice led to variable outcomes in the recipient mice. Microbiome analysis revealed that a higher abundance of butyrate-producing bacteria was associated with the resistant phenotype. Quantification of short-chain fatty acid (SCFA) levels before and after infection revealed increased concentrations of acetate, butyrate and propionate in mice with delayed colonization. Addition of physiological concentrations of butyrate, but not of acetate and/or propionate strongly impaired growth of C. rodentium in vitro. In vivo supplementation of susceptible, antibiotic-treated and germ-free mice with butyrate led to the same level of protection, notably only when cecal butyrate concentration reached a concentration higher than 50 nmol/mg indicating a critical threshold for protection. In the recent years, commensal-derived primary and secondary bacterial metabolites emerged as potent modulators of hosts susceptibility to infection. Our results provide evidence that variations in SCFA production in mice fed fibre-rich chow-based diets modulate susceptibility to colonization with Enterobacteriaceae not only in antibiotic-disturbed ecosystems but even in undisturbed microbial communities. These findings emphasise the need for microbiota normalization across laboratory mouse lines for infection experiments with the model-pathogen C. rodentium independent of investigations of diet and antibiotic usage. The distinct composition of the gut microbiota in each individual results in variable metabolic activity and output of these communities, which influences the host, including resistance to enteric pathogens. Lack of reproducibility in biomedical research is nowadays frequently attributed to the microbiota, but little is known about which specific members and metabolites contribute to disease severity. Here, we use genetically identical mouse lines with variable microbiota compositions on a standardized diet and observed highly variable colonization with the enteric pathogen Citrobacter rodentium without antibiotics intervention. We found the same differences in formerly germ-free animals harbouring the respective donors microbiota and also in vitro by coculturing cecal bacteria from resistant and susceptible animals with C. rodentium showing that the phenotype is fully dependent on differences in the microbiota. We analysed the microbiome composition and found a higher abundance of butyrate-producing bacteria as well as increased levels of butyrate in resistant mice. By supplementation of susceptible and germ-free animals with butyrate, we could significantly lower the levels of colonization highlighting that commensal-derived primary and secondary bacterial metabolites are highly variable between laboratory animals from different vendors and are potent modulators of hosts susceptibility to infection with C. rodentium.
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Kusumo PD, Maulahela H, Utari AP, Surono IS, Soebandrio A, Abdullah M. Probiotic Lactobacillus plantarum IS 10506 supplementation increase SCFA of women with functional constipation. IRANIAN JOURNAL OF MICROBIOLOGY 2019; 11:389-396. [PMID: 32148669 PMCID: PMC7049320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND AND OBJECTIVES Gut microbiota influences our health via multiple mechanisms. Microbiota produced Short Chain Fatty Acid (SCFA) as an energy to maintain gut ecosystem and physiology. Dysbiosis is correlated with SCFA imbalance which in turn resulted in physiological abnormalities in the intestine, such as functional constipation. MATERIALS AND METHODS Randomized Double-Blind Controlled Trial (RCT) was conducted on women with functional constipation (n=37) in the community of Jakarta and profile of SCFA was assessed by using GC-MS from the stool after 21 days supplementation of fermented milk (placebo and probiotic). RESULTS Probiotic supplementation significantly influenced acetate titer (p=0,032) marginally significant for propionate and butyrate (p=0.063 and p=0.068, respectively) and the respondent with increasing SCFA's metabolite are higher in probiotic group compared to the respondents in placebo group. Acetate is the highest SCFA titer found in faeces samples of women with functional constipation. CONCLUSION Probiotic Lactobacillus plantarum IS 10506 supplementation influenced all the SCFA parameter (acetate, propionate and butyrate).
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Affiliation(s)
- Pratiwi Dyah Kusumo
- Biomedic Doctoral Programme, School of Medicine, Universitas Indonesia, Jakarta, Indonesia
- Department of Biomedic, School of Medicine, Universitas Kristen Indonesia, Jakarta, Indonesia
| | - Hasan Maulahela
- Department of Gastroenterology, School of Medicine, Universitas Indonesia, Jakarta, Indonesia
| | - Amanda Pitarini Utari
- Department of Gastroenterology, School of Medicine, Universitas Indonesia, Jakarta, Indonesia
| | - Ingrid S. Surono
- Department of Food Technology, Faculty of Engineering, Bina Nusantara University, Jakarta, Indonesia
| | - Amin Soebandrio
- Eijkman Biology Molecular Institute, Jakarta, Indonesia
- Department of Microbiology, School of Medicine, Universitas Indonesia, Jakarta, Indonesia
| | - Murdani Abdullah
- Department of Gastroenterology, School of Medicine, Universitas Indonesia, Jakarta, Indonesia
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27
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Patel J, Yin HB, Bauchan G, Mowery J. Inhibition of Escherichia coli O157:H7 and Salmonella enterica virulence factors by benzyl isothiocyanate. Food Microbiol 2019; 86:103303. [PMID: 31703885 DOI: 10.1016/j.fm.2019.103303] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 08/03/2019] [Accepted: 08/10/2019] [Indexed: 01/17/2023]
Abstract
Escherichia coli O157:H7 and Salmonella enterica are foodborne pathogens with major public health concern in the U.S. These pathogens utilize several virulence factors to initiate infections in humans. The antimicrobial effect of seven glucosinolate hydrolysis compounds against Salmonella and E. coli O157:H7 was investigated by the disc diffusion assay. Among the tested compounds, benzyl isothiocyanate (BIT), which exerted the highest antimicrobial activity, was evaluated for its anti-virulence properties against these pathogens. The effect of BIT on motility of Salmonella and E. coli O157:H7 and Shiga toxin production by E. coli O157:H7 was determined by the motility assay and ELISA procedure, respectively. Confocal and transmission electron microscopy (TEM) procedures were used to determine bacterial damage at the cellular level. Results revealed that sub-inhibitory concentrations (SICs) of BIT significantly inhibited the motility of both bacteria (P < 0.05). Shiga toxin production by E. coli O157:H7 was decreased by ~32% in the presence of BIT at SICs. TEM results showed the disruption of outer membrane, release of cytoplasmic contents, and cell lysis following BIT treatment. Results suggest that BIT could be potentially used to attenuate Salmonella and E. coli O157:H7 infections by reducing the virulence factors including bacterial motility and Shiga toxin production.
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Affiliation(s)
- Jitendra Patel
- U.S. Department of Agriculture, Agricultural Research Service, Environmental and Microbial Food Safety Laboratory, Beltsville, MD 20705, USA.
| | - Hsin-Bai Yin
- U.S. Department of Agriculture, Agricultural Research Service, Environmental and Microbial Food Safety Laboratory, Beltsville, MD 20705, USA
| | - Gary Bauchan
- U.S. Department of Agriculture, Agricultural Research Service, SGIL Electron and Confocal Microscopy Unit, Beltsville, MD 20705, USA
| | - Joseph Mowery
- U.S. Department of Agriculture, Agricultural Research Service, SGIL Electron and Confocal Microscopy Unit, Beltsville, MD 20705, USA
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28
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Tovaglieri A, Sontheimer-Phelps A, Geirnaert A, Prantil-Baun R, Camacho DM, Chou DB, Jalili-Firoozinezhad S, de Wouters T, Kasendra M, Super M, Cartwright MJ, Richmond CA, Breault DT, Lacroix C, Ingber DE. Species-specific enhancement of enterohemorrhagic E. coli pathogenesis mediated by microbiome metabolites. MICROBIOME 2019; 7:43. [PMID: 30890187 PMCID: PMC6425591 DOI: 10.1186/s40168-019-0650-5] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Accepted: 02/21/2019] [Indexed: 05/24/2023]
Abstract
BACKGROUND Species-specific differences in tolerance to infection are exemplified by the high susceptibility of humans to enterohemorrhagic Escherichia coli (EHEC) infection, whereas mice are relatively resistant to this pathogen. This intrinsic species-specific difference in EHEC infection limits the translation of murine research to human. Furthermore, studying the mechanisms underlying this differential susceptibility is a difficult problem due to complex in vivo interactions between the host, pathogen, and disparate commensal microbial communities. RESULTS We utilize organ-on-a-chip (Organ Chip) microfluidic culture technology to model damage of the human colonic epithelium induced by EHEC infection, and show that epithelial injury is greater when exposed to metabolites derived from the human gut microbiome compared to mouse. Using a multi-omics approach, we discovered four human microbiome metabolites-4-methyl benzoic acid, 3,4-dimethylbenzoic acid, hexanoic acid, and heptanoic acid-that are sufficient to mediate this effect. The active human microbiome metabolites preferentially induce expression of flagellin, a bacterial protein associated with motility of EHEC and increased epithelial injury. Thus, the decreased tolerance to infection observed in humans versus other species may be due in part to the presence of compounds produced by the human intestinal microbiome that actively promote bacterial pathogenicity. CONCLUSION Organ-on-chip technology allowed the identification of specific human microbiome metabolites modulating EHEC pathogenesis. These identified metabolites are sufficient to increase susceptibility to EHEC in our human Colon Chip model and they contribute to species-specific tolerance. This work suggests that higher concentrations of these metabolites could be the reason for higher susceptibility to EHEC infection in certain human populations, such as children. Furthermore, this research lays the foundation for therapeutic-modulation of microbe products in order to prevent and treat human bacterial infection.
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Affiliation(s)
- Alessio Tovaglieri
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
- Department of Health Sciences and Technology, ETH Zurich, 8092, Zurich, Switzerland
| | - Alexandra Sontheimer-Phelps
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
- Department of Biology, University of Freiburg, 79085, Freiburg, Germany
| | - Annelies Geirnaert
- Department of Health Sciences and Technology, ETH Zurich, 8092, Zurich, Switzerland
| | - Rachelle Prantil-Baun
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
| | - Diogo M Camacho
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
| | - David B Chou
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
- Department of Pathology, Massachusetts General Hospital, Boston, MA, 02115, USA
| | - Sasan Jalili-Firoozinezhad
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
- Department of Bioengineering and iBB, Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1649-004, Lisbon, Portugal
| | - Tomás de Wouters
- Department of Health Sciences and Technology, ETH Zurich, 8092, Zurich, Switzerland
| | - Magdalena Kasendra
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
- Present Address: Emulate Inc., 27 Drydock Avenue, Boston, MA, 02210, USA
| | - Michael Super
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
| | - Mark J Cartwright
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
| | - Camilla A Richmond
- Division of Gastroenterology, Boston Children's Hospital, Boston, MA, 02115, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA
- Harvard Stem Cell Institute, Harvard University, Boston, MA, 02139, USA
| | - David T Breault
- Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA
- Harvard Stem Cell Institute, Harvard University, Boston, MA, 02139, USA
- Division of Endocrinology, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Christophe Lacroix
- Department of Health Sciences and Technology, ETH Zurich, 8092, Zurich, Switzerland
| | - Donald E Ingber
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA.
- Vascular Biology Program and Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA.
- Harvard John A. Paulson School of Engineering and Applied Sciences, Cambridge, MA, 02139, USA.
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29
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Iacob S, Iacob DG, Luminos LM. Intestinal Microbiota as a Host Defense Mechanism to Infectious Threats. Front Microbiol 2019; 9:3328. [PMID: 30761120 PMCID: PMC6362409 DOI: 10.3389/fmicb.2018.03328] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 12/21/2018] [Indexed: 12/12/2022] Open
Abstract
The intestinal microbiota is a complex microbial community, with diverse and stable populations hosted by the gastrointestinal tract since birth. This ecosystem holds multiple anti-infectious, anti-inflammatory, and immune modulating roles decisive for intestinal homeostasis. Among these, colonization resistance refers to the dynamic antagonistic interactions between commensals and pathogenic flora. Hence, gut bacteria compete for the same intestinal niches and substrates, while also releasing antimicrobial substances such as bacteriocines and changing the environmental conditions. Short chain fatty acids (SCFAs) generated in anaerobic conditions prompt epigenetic regulatory mechanisms that favor a tolerogenic immune response. In addition, the commensal flora is involved in the synthesis of bactericidal products, namely secondary biliary acids or antimicrobial peptides (AMPs) such as cathellicidin-LL37, an immunomodulatory, antimicrobial, and wound healing peptide. Gut microbiota is protected through symbiotic relations with the hosting organism and by quorum sensing, a specific cell-to-cell communication system. Any alterations of these relationships favor the uncontrollable multiplication of the resident pathobionts or external entero-pathogens, prompting systemic translocations, inflammatory reactions, or exacerbations of bacterial virulence mechanisms (T6SS, T3SS) and ultimately lead to gastrointestinal or systemic infections. The article describes the metabolic and immunological mechanisms through which the intestinal microbiota is both an ally of the organism against enteric pathogens and an enemy that favors the development of infections.
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Affiliation(s)
- Simona Iacob
- Department of Infectious Diseases, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.,National Institute of Infectious Diseases "Prof. Dr. Matei Bals", Bucharest, Romania
| | - Diana Gabriela Iacob
- National Institute of Infectious Diseases "Prof. Dr. Matei Bals", Bucharest, Romania
| | - Luminita Monica Luminos
- Department of Infectious Diseases, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.,National Institute of Infectious Diseases "Prof. Dr. Matei Bals", Bucharest, Romania
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30
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Modulation of Enterohaemorrhagic Escherichia coli Survival and Virulence in the Human Gastrointestinal Tract. Microorganisms 2018; 6:microorganisms6040115. [PMID: 30463258 PMCID: PMC6313751 DOI: 10.3390/microorganisms6040115] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 11/16/2018] [Accepted: 11/18/2018] [Indexed: 01/05/2023] Open
Abstract
Enterohaemorrhagic Escherichia coli (EHEC) is a major foodborne pathogen responsible for human diseases ranging from diarrhoea to life-threatening complications. Survival of the pathogen and modulation of virulence gene expression along the human gastrointestinal tract (GIT) are key features in bacterial pathogenesis, but remain poorly described, due to a paucity of relevant model systems. This review will provide an overview of the in vitro and in vivo studies investigating the effect of abiotic (e.g., gastric acid, bile, low oxygen concentration or fluid shear) and biotic (e.g., gut microbiota, short chain fatty acids or host hormones) parameters of the human gut on EHEC survival and/or virulence (especially in relation with motility, adhesion and toxin production). Despite their relevance, these studies display important limitations considering the complexity of the human digestive environment. These include the evaluation of only one single digestive parameter at a time, lack of dynamic flux and compartmentalization, and the absence of a complex human gut microbiota. In a last part of the review, we will discuss how dynamic multi-compartmental in vitro models of the human gut represent a novel platform for elucidating spatial and temporal modulation of EHEC survival and virulence along the GIT, and provide new insights into EHEC pathogenesis.
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31
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Baker LY, Hobby CR, Siv AW, Bible WC, Glennon MS, Anderson DM, Symes SJ, Giles DK. Pseudomonas aeruginosa responds to exogenous polyunsaturated fatty acids (PUFAs) by modifying phospholipid composition, membrane permeability, and phenotypes associated with virulence. BMC Microbiol 2018; 18:117. [PMID: 30217149 PMCID: PMC6137939 DOI: 10.1186/s12866-018-1259-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 09/05/2018] [Indexed: 12/20/2022] Open
Abstract
Background Pseudomonas aeruginosa, a common opportunistic pathogen, is known to cause infections in a variety of compromised human tissues. An emerging mechanism for microbial survival is the incorporation of exogenous fatty acids to alter the cell’s membrane phospholipid profile. With these findings, we show that exogenous fatty acid exposure leads to changes in bacterial membrane phospholipid structure, membrane permeability, virulence phenotypes and consequent stress responses that may influence survival and persistence of Pseudomonas aeruginosa. Results Thin-layer chromatography and ultra performance liquid chromatography / ESI-mass spectrometry indicated alteration of bacterial phospholipid profiles following growth in the presence of polyunsaturated fatty acids (PUFAs) (ranging in carbon length and unsaturation). The exogenously supplied fatty acids were incorporated into the major bacterial phospholipids phosphatidylethanolamine and phosphatidylglycerol. The incorporation of fatty acids increased membrane permeability as judged by both accumulation and exclusion of ethidium bromide. Individual fatty acids were identified as modifying resistance to the cyclic peptide antibiotics polymyxin B and colistin, but not the beta-lactam imipenem. Biofilm formation was increased by several PUFAs and significant fluctuations in swimming motility were observed. Conclusions Our results emphasize the relevance and complexity of exogenous fatty acids in the membrane physiology and pathobiology of a medically important pathogen. P. aeruginosa exhibits versatility with regard to utilization of and response to exogenous fatty acids, perhaps revealing potential strategies for prevention and control of infection. Electronic supplementary material The online version of this article (10.1186/s12866-018-1259-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lyssa Y Baker
- Department of Biology, Geology, and Environmental Science, The University of Tennessee at Chattanooga, Chattanooga, TN, USA
| | - Chelsea R Hobby
- Department of Biology, Geology, and Environmental Science, The University of Tennessee at Chattanooga, Chattanooga, TN, USA
| | - Andrew W Siv
- Department of Biology, Geology, and Environmental Science, The University of Tennessee at Chattanooga, Chattanooga, TN, USA
| | - William C Bible
- Department of Biology, Geology, and Environmental Science, The University of Tennessee at Chattanooga, Chattanooga, TN, USA
| | - Michael S Glennon
- Department of Biology, Geology, and Environmental Science, The University of Tennessee at Chattanooga, Chattanooga, TN, USA
| | - Derek M Anderson
- Department of Chemistry and Physics, The University of Tennessee at Chattanooga, Chattanooga, TN, USA
| | - Steven J Symes
- Department of Chemistry and Physics, The University of Tennessee at Chattanooga, Chattanooga, TN, USA
| | - David K Giles
- Department of Biology, Geology, and Environmental Science, The University of Tennessee at Chattanooga, Chattanooga, TN, USA.
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32
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Martens EC, Neumann M, Desai MS. Interactions of commensal and pathogenic microorganisms with the intestinal mucosal barrier. Nat Rev Microbiol 2018; 16:457-470. [DOI: 10.1038/s41579-018-0036-x] [Citation(s) in RCA: 284] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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33
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Sudo N, Soma A, Iyoda S, Oshima T, Ohto Y, Saito K, Sekine Y. Small RNA Esr41 inversely regulates expression of LEE and flagellar genes in enterohaemorrhagic Escherichia coli. MICROBIOLOGY-SGM 2018; 164:821-834. [PMID: 29580371 DOI: 10.1099/mic.0.000652] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Enterohaemorrhagic Escherichia coli (EHEC) is a life-threatening human pathogen worldwide. The locus of enterocyte effacement (LEE) in EHEC encodes a type three secretion system and effector proteins, all of which are essential for bacterial adherence to host cells. When LEE expression is activated, flagellar gene expression is down-regulated because bacterial flagella induce the immune responses of host cells at the infection stage. Therefore, this inverse regulation is also important for EHEC infection. We report here that a small regulatory RNA (sRNA), Esr41, mediates LEE repression and flagellar gene activation. Multiple copies of esr41 abolished LEE expression by down-regulating the expression of ler and pch, which encode positive regulators of LEE. This regulation led to reduced EHEC adhesion to host cells. Translational gene-reporter fusion experiments revealed that Esr41 regulates ler expression at a post-transcriptional level, and pch transcription, probably via an unknown target of Esr41. Esr41-mediated ler and pch repression was not observed in cells lacking hfq, which encodes an RNA-binding protein essential for most sRNA functions, indicating that Esr41 acts in an Hfq-dependent manner. We previously reported an increase in cell motility induced by Esr41. This motility enhancement was also observed in EHEC lacking ler, showing that Esr41-mediated enhancement of cell motility is in a ler-independent manner. In addition, Esr41 activated the expression of flagellar Class 3 genes by indirectly inducing the transcription of fliA, which encodes the sigma factor for flagellar synthesis. These results suggest that Esr41 plays important roles in the inverse regulation of LEE and flagellar gene expression.
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Affiliation(s)
- Naoki Sudo
- Department of Life Science, College of Science, Rikkyo University, Toshima, Tokyo, Japan.,Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku, Tokyo, Japan
| | - Akiko Soma
- Graduate School of Horticulture, Chiba University, Matsudo, Chiba, Japan
| | - Sunao Iyoda
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku, Tokyo, Japan
| | - Taku Oshima
- Department of Biotechnology, Toyama Prefectural University, Imizu, Toyama, Japan
| | - Yui Ohto
- Department of Life Science, College of Science, Rikkyo University, Toshima, Tokyo, Japan
| | - Kenta Saito
- Department of Life Science, College of Science, Rikkyo University, Toshima, Tokyo, Japan
| | - Yasuhiko Sekine
- Department of Life Science, College of Science, Rikkyo University, Toshima, Tokyo, Japan
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Kuo CJ, Wang ST, Lin CM, Chiu HC, Huang CR, Lee DY, Chang GD, Chou TC, Chen JW, Chen CS. A multi-omic analysis reveals the role of fumarate in regulating the virulence of enterohemorrhagic Escherichia coli. Cell Death Dis 2018. [PMID: 29515100 PMCID: PMC5841434 DOI: 10.1038/s41419-018-0423-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The enteric pathogen enterohemorrhagic Escherichia coli (EHEC) is responsible for outbreaks of bloody diarrhea and hemolytic uremic syndrome (HUS) worldwide. Several molecular mechanisms have been described for the pathogenicity of EHEC; however, the role of bacterial metabolism in the virulence of EHEC during infection in vivo remains unclear. Here we show that aerobic metabolism plays an important role in the regulation of EHEC virulence in Caenorhabditis elegans. Our functional genomic analyses showed that disruption of the genes encoding the succinate dehydrogenase complex (Sdh) of EHEC, including the sdhA gene, attenuated its toxicity toward C. elegans animals. Sdh converts succinate to fumarate and links the tricarboxylic acid (TCA) cycle and the electron transport chain (ETC) simultaneously. Succinate accumulation and fumarate depletion in the EHEC sdhA mutant cells were also demonstrated to be concomitant by metabolomic analyses. Moreover, fumarate replenishment to the sdhA mutant significantly increased its virulence toward C. elegans. These results suggest that the TCA cycle, ETC, and alteration in metabolome all account for the attenuated toxicity of the sdhA mutant, and Sdh catabolite fumarate in particular plays a critical role in the regulation of EHEC virulence. In addition, we identified the tryptophanase (TnaA) as a downstream virulence determinant of SdhA using a label-free proteomic method. We demonstrated that expression of tnaA is regulated by fumarate in EHEC. Taken together, our multi-omic analyses demonstrate that sdhA is required for the virulence of EHEC, and aerobic metabolism plays important roles in the pathogenicity of EHEC infection in C. elegans. Moreover, our study highlights the potential targeting of SdhA, if druggable, as alternative preventive or therapeutic strategies by which to combat EHEC infection.
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Affiliation(s)
- Cheng-Ju Kuo
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Sin-Tian Wang
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chia-Mei Lin
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Hao-Chieh Chiu
- Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University, Taipei, Taiwan
| | - Cheng-Rung Huang
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Der-Yen Lee
- The Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan.,Graduate Institute of Biochemical Sciences, Technology Commons, Center for Systems Biology, National Taiwan University, Taipei, Taiwan
| | - Geen-Dong Chang
- Graduate Institute of Biochemical Sciences, Technology Commons, Center for Systems Biology, National Taiwan University, Taipei, Taiwan
| | - Ting-Chen Chou
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Jenn-Wei Chen
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan. .,Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
| | - Chang-Shi Chen
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan. .,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
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35
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Regulation of the Locus of Enterocyte Effacement in Attaching and Effacing Pathogens. J Bacteriol 2017; 200:JB.00336-17. [PMID: 28760850 DOI: 10.1128/jb.00336-17] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Attaching and effacing (AE) pathogens colonize the gut mucosa using a type three secretion system (T3SS) and a suite of effector proteins. The locus of enterocyte effacement (LEE) is the defining genetic feature of the AE pathogens, encoding the T3SS and the core effector proteins necessary for pathogenesis. Extensive research has revealed a complex regulatory network that senses and responds to a myriad of host- and microbiota-derived signals in the infected gut to control transcription of the LEE. These signals include microbiota-liberated sugars and metabolites in the gut lumen, molecular oxygen at the gut epithelium, and host hormones. Recent research has revealed that AE pathogens also recognize physical signals, such as attachment to the epithelium, and that the act of effector translocation remodels gene expression in infecting bacteria. In this review, we summarize our knowledge to date and present an integrated view of how chemical, geographical, and physical cues regulate the virulence program of AE pathogens during infection.
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36
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Bacterial Chat: Intestinal Metabolites and Signals in Host-Microbiota-Pathogen Interactions. Infect Immun 2017; 85:IAI.00476-17. [PMID: 28947641 DOI: 10.1128/iai.00476-17] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Intestinal bacteria employ microbial metabolites from the microbiota and chemical signaling during cell-to-cell communication to regulate several cellular functions. Pathogenic bacteria are extremely efficient in orchestrating their response to these signals through complex signaling transduction systems. Precise coordination and interpretation of these multiple chemical cues is important within the gastrointestinal (GI) tract. Enteric foodborne pathogens, such as enterohemorrhagic Escherichia coli (EHEC) and Salmonella enterica serovar Typhimurium, or the surrogate murine infection model for EHEC, Citrobacter rodentium, are all examples of microorganisms that modulate the expression of their virulence repertoire in response to signals from the microbiota or the host, such as autoinducer-3 (AI-3), epinephrine (Epi), and norepinephrine (NE). The QseBC and QseEF two-component systems, shared by these pathogens, are involved in sensing these signals. We review how these signaling systems sense and relay these signals to drive bacterial gene expression; specifically, to modulate virulence. We also review how bacteria chat via chemical signals integrated with metabolite recognition and utilization to promote successful associations among enteric pathogens, the microbiota, and the host.
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37
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Exogenous Polyunsaturated Fatty Acids Impact Membrane Remodeling and Affect Virulence Phenotypes among Pathogenic Vibrio Species. Appl Environ Microbiol 2017; 83:AEM.01415-17. [PMID: 28864654 DOI: 10.1128/aem.01415-17] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 08/25/2017] [Indexed: 01/24/2023] Open
Abstract
The pathogenic Vibrio species (V. cholerae, V. parahaemolyticus, and V. vulnificus) represent a constant threat to human health, causing foodborne and skin wound infections as a result of ingestion of or exposure to contaminated water and seafood. Recent studies have highlighted Vibrio's ability to acquire fatty acids from environmental sources and assimilate them into cell membranes. The possession and conservation of such machinery provokes consideration of fatty acids as important factors in the pathogenic lifestyle of Vibrio species. The findings here link exogenous fatty acid exposure to changes in bacterial membrane phospholipid structure, permeability, phenotypes associated with virulence, and consequent stress responses that may impact survival and persistence of pathogenic Vibrio species. Polyunsaturated fatty acids (PUFAs) (ranging in carbon length and unsaturation) supplied in growth medium were assimilated into bacterial phospholipids, as determined by thin-layer chromatography and liquid chromatography-mass spectrometry. The incorporation of fatty acids variably affected membrane permeability, as judged by uptake of the hydrophobic compound crystal violet. For each species, certain fatty acids were identified as affecting resistance to antimicrobial peptide treatment. Significant fluctuations were observed with regard to both motility and biofilm formation following growth in the presence of individual PUFAs. Our results illustrate the important and complex roles of exogenous fatty acids in the membrane physiology and virulence of a bacterial genus that inhabits aquatic and host environments containing an abundance of diverse fatty acids.IMPORTANCE Bacterial responses to fatty acids include, but are not limited to, degradation for metabolic gain, modification of membrane lipids, alteration of protein function, and regulation of gene expression. Vibrio species exhibit significant diversity with regard to the machinery known to participate in the uptake and incorporation of fatty acids into their membranes. Both aquatic and host niches occupied by Vibrio are rife with various free fatty acids and fatty acid-containing lipids. The roles of fatty acids in the environmental survival and pathogenesis of bacteria have begun to emerge and are expected to expand significantly. The current study demonstrates the responsiveness of V. cholerae, V. parahaemolyticus, and V. vulnificus to exogenous PUFAs. In addition to phospholipid remodeling, PUFA assimilation impacts membrane permeability, motility, biofilm formation, and resistance to polymyxin B.
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38
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Urashima A, Sanou A, Yen H, Tobe T. Enterohaemorrhagic Escherichia coli produces outer membrane vesicles as an active defence system against antimicrobial peptide LL-37. Cell Microbiol 2017. [PMID: 28622430 DOI: 10.1111/cmi.12758] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Antimicrobial peptides (AMPs) are important components of the innate immune system. Enterohaemorrhagic Escherichia coli (EHEC), a food-borne pathogen causing serious diarrheal diseases, must overcome attack by AMPs. Here, we show that resistance of EHEC against human cathelicidin LL-37, a primary AMP, was enhanced by butyrate, which has been shown to act as a stimulant for the expression of virulence genes. The increase of resistance depended on the activation of the ompT gene, which encodes the outer membrane protease OmpT for LL-37. The expression of the ompT gene was enhanced through the activation system for virulence genes. The increase in ompT expression did not result in an increase in OmpT protease in bacteria but in enhancement of the production of OmpT-loaded outer membrane vesicles (OMVs), which primarily contributed to the increase in LL-37-resistance. Furthermore, a sublethal dosage of LL-37 stimulated the production of OMVs. Finally, we showed that OMVs produced by OmpT-positive strains protect the OmpT-negative strain, which is susceptible to LL-37 by itself more efficiently than OMVs from the ompT mutant. These results indicate that EHEC enhances the secretion of OmpT-loaded OMVs in coordination with the activation of virulence genes during infection and blocks bacterial cell attack by LL-37.
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Affiliation(s)
- Akiko Urashima
- Department of Biomedical Informatics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Ayano Sanou
- Department of Biomedical Informatics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Hilo Yen
- Department of Biomedical Informatics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Toru Tobe
- Department of Biomedical Informatics, Osaka University Graduate School of Medicine, Osaka, Japan
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39
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Sirobhushanam S, Galva C, Saunders LP, Sen S, Jayaswal R, Wilkinson BJ, Gatto C. Utilization of multiple substrates by butyrate kinase from Listeria monocytogenes. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1862:283-290. [PMID: 27940001 DOI: 10.1016/j.bbalip.2016.12.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 11/20/2016] [Accepted: 12/04/2016] [Indexed: 12/17/2022]
Abstract
Listeria monocytogenes, the causative agent of listeriosis, can build up to dangerous levels in refrigerated foods potentially leading to expensive product recalls. An important aspect of the bacterium's growth at low temperatures is its ability to increase the branched-chain fatty acid anteiso C15:0 content of its membrane at lower growth temperatures, which imparts greater membrane fluidity. Mutants in the branched-chain α-keto dehydrogenase (bkd) complex are deficient in branched-chain fatty acids (BCFAs,) but these can be restored by feeding C4 and C5 branched-chain carboxylic acids (BCCAs). This suggests the presence of an alternate pathway for production of acyl CoA precursors for fatty acid biosynthesis. We hypothesize that the alternate pathway is composed of butyrate kinase (buk) and phosphotransbutyrylase (ptb) encoded in the bkd complex which produce acyl CoA products by their sequential action through the metabolism of carboxylic acids. We determined the steady state kinetics of recombinant His-tagged Buk using 11 different straight-chain and BCCA substrates in the acyl phosphate forming direction. Buk demonstrated highest catalytic efficiency with pentanoate as the substrate. Low product formation observed with acetate (C2) and hexanoate (C6) as the substrates indicates that Buk is not involved in either acetate metabolism or long chain carboxylic acid activation. We were also able to show that Buk catalysis occurs through a ternary complex intermediate. Additionally, Buk demonstrates a strong preference for BCCAs at low temperatures. These results indicate that Buk may be involved in the activation and assimilation of exogenous carboxylic acids for membrane fatty acid biosynthesis.
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Affiliation(s)
- Sirisha Sirobhushanam
- School of Biological Sciences, Illinois State University, Normal, IL 61790, United States
| | - Charitha Galva
- School of Biological Sciences, Illinois State University, Normal, IL 61790, United States
| | - Lauren P Saunders
- School of Biological Sciences, Illinois State University, Normal, IL 61790, United States
| | - Suranjana Sen
- School of Biological Sciences, Illinois State University, Normal, IL 61790, United States
| | - Radheshyam Jayaswal
- School of Biological Sciences, Illinois State University, Normal, IL 61790, United States
| | - Brian J Wilkinson
- School of Biological Sciences, Illinois State University, Normal, IL 61790, United States
| | - Craig Gatto
- School of Biological Sciences, Illinois State University, Normal, IL 61790, United States.
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40
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Cordonnier C, Thévenot J, Etienne-Mesmin L, Alric M, Livrelli V, Blanquet-Diot S. Probiotic and enterohemorrhagic Escherichia coli: An effective strategy against a deadly enemy? Crit Rev Microbiol 2016; 43:116-132. [PMID: 27798976 DOI: 10.1080/1040841x.2016.1185602] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Enterohemorrhagic Escherichia coli (EHEC) are major food-borne pathogens that constitute a serious public health threat. Currently, there is no specific treatment available for EHEC infections in human creating an urgent need for the development of alternative therapeutic strategies. Among them, one of the most promising approaches is the use of probiotic microorganisms. Even if many studies have shown the antagonistic effects of probiotic bacteria or yeast on EHEC survival, virulence, adhesion on intestinal epithelium or pathogen-induced inflammatory responses, mechanisms mediating their beneficial effects remain unclear. This review describes EHEC pathogenesis and novel therapeutic strategies, with a particular emphasis on probiotics. The interests and limits of a probiotic-based approach and the way it might be incorporated into global health strategies against EHEC infections will be discussed.
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Affiliation(s)
- Charlotte Cordonnier
- a EA 4678 CIDAM, "Conception, Ingénierie et Développement de l'Aliment et du Médicament", Centre de Recherche en Nutrition Humaine Auvergne , Université d'Auvergne , Clermont-Ferrand , France.,b M2iSH, "Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte" , UMR Inserm/Université d'Auvergne U1071, USC-INRA 2018, Centre de Recherche en Nutrition Humaine Auvergne, Université d'Auvergne , Clermont-Ferrand , France
| | - Jonathan Thévenot
- a EA 4678 CIDAM, "Conception, Ingénierie et Développement de l'Aliment et du Médicament", Centre de Recherche en Nutrition Humaine Auvergne , Université d'Auvergne , Clermont-Ferrand , France.,b M2iSH, "Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte" , UMR Inserm/Université d'Auvergne U1071, USC-INRA 2018, Centre de Recherche en Nutrition Humaine Auvergne, Université d'Auvergne , Clermont-Ferrand , France
| | - Lucie Etienne-Mesmin
- a EA 4678 CIDAM, "Conception, Ingénierie et Développement de l'Aliment et du Médicament", Centre de Recherche en Nutrition Humaine Auvergne , Université d'Auvergne , Clermont-Ferrand , France.,b M2iSH, "Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte" , UMR Inserm/Université d'Auvergne U1071, USC-INRA 2018, Centre de Recherche en Nutrition Humaine Auvergne, Université d'Auvergne , Clermont-Ferrand , France
| | - Monique Alric
- a EA 4678 CIDAM, "Conception, Ingénierie et Développement de l'Aliment et du Médicament", Centre de Recherche en Nutrition Humaine Auvergne , Université d'Auvergne , Clermont-Ferrand , France
| | - Valérie Livrelli
- b M2iSH, "Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte" , UMR Inserm/Université d'Auvergne U1071, USC-INRA 2018, Centre de Recherche en Nutrition Humaine Auvergne, Université d'Auvergne , Clermont-Ferrand , France.,c Service de Bactériologie , CHU Clermont-Ferrand , Clermont-Ferrand , France
| | - Stéphanie Blanquet-Diot
- a EA 4678 CIDAM, "Conception, Ingénierie et Développement de l'Aliment et du Médicament", Centre de Recherche en Nutrition Humaine Auvergne , Université d'Auvergne , Clermont-Ferrand , France
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41
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Baskaran SA, Kollanoor-Johny A, Nair MS, Venkitanarayanan K. Efficacy of Plant-Derived Antimicrobials in Controlling Enterohemorrhagic Escherichia coli Virulence In Vitro. J Food Prot 2016; 79:1965-1970. [PMID: 28221905 DOI: 10.4315/0362-028x.jfp-16-104] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Escherichia coli O157:H7 is a major foodborne pathogen that can cause serious human illness characterized by hemorrhagic diarrhea and kidney failure. The pathology of enterohemorrhagic E. coli O157:H7 (EHEC) infection is primarily mediated by verotoxins, which bind to the globotriaosylceramide receptor on host cells. Antibiotics are contraindicated for treating EHEC infection because they lead to increased verotoxin release, thereby increasing the risk of renal failure and death in patients. Thus, alternative strategies are needed for controlling EHEC infections in humans. This study investigated the effect of subinhibitory concentrations of five plant-derived antimicrobial agents (PDAs) that are generally considered as safe, i.e., trans-cinnamaldehyde, eugenol, carvacrol, thymol, and β-resorcylic acid, on EHEC motility, adhesion to human intestinal epithelial cells, verotoxin production, and virulence gene expression. All tested PDAs reduced EHEC motility and attachment to human intestinal epithelial cells (P < 0.05) and decreased verotoxin synthesis by EHEC. The reverse transcription real-time PCR data revealed that PDAs decreased the expression of critical virulence genes in EHEC (P < 0.05). The results collectively suggest that these PDAs could be used to reduce EHEC virulence, but follow-up studies in animal models are necessary to validate these findings.
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Affiliation(s)
- Sangeetha Ananda Baskaran
- Department of Veterinary Public Health & Epidemiology, Veterinary College & Research Institute, Orathanadu, Tamil Nadu, India 614 625
| | - Anup Kollanoor-Johny
- Department of Animal Science, University of Minnesota, St. Paul, Minnesota 55108, USA
| | - Meera Surendran Nair
- Department of Animal Science, University of Connecticut, Storrs, Connecticut 06269, USA
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42
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Kim J, Kim MS, Koh AY, Xie Y, Zhan X. FMAP: Functional Mapping and Analysis Pipeline for metagenomics and metatranscriptomics studies. BMC Bioinformatics 2016; 17:420. [PMID: 27724866 PMCID: PMC5057277 DOI: 10.1186/s12859-016-1278-0] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 09/26/2016] [Indexed: 12/12/2022] Open
Abstract
Background Given the lack of a complete and comprehensive library of microbial reference genomes, determining the functional profile of diverse microbial communities is challenging. The available functional analysis pipelines lack several key features: (i) an integrated alignment tool, (ii) operon-level analysis, and (iii) the ability to process large datasets. Results Here we introduce our open-sourced, stand-alone functional analysis pipeline for analyzing whole metagenomic and metatranscriptomic sequencing data, FMAP (Functional Mapping and Analysis Pipeline). FMAP performs alignment, gene family abundance calculations, and statistical analysis (three levels of analyses are provided: differentially-abundant genes, operons and pathways). The resulting output can be easily visualized with heatmaps and functional pathway diagrams. FMAP functional predictions are consistent with currently available functional analysis pipelines. Conclusion FMAP is a comprehensive tool for providing functional analysis of metagenomic/metatranscriptomic sequencing data. With the added features of integrated alignment, operon-level analysis, and the ability to process large datasets, FMAP will be a valuable addition to the currently available functional analysis toolbox. We believe that this software will be of great value to the wider biology and bioinformatics communities. Electronic supplementary material The online version of this article (doi:10.1186/s12859-016-1278-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jiwoong Kim
- Department of Clinical Sciences, Quantitative Biomedical Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA.,Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA
| | - Min Soo Kim
- Department of Clinical Sciences, Quantitative Biomedical Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA.,Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA
| | - Andrew Y Koh
- Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA.,Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA.,Department of Microbiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA
| | - Yang Xie
- Department of Clinical Sciences, Quantitative Biomedical Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA. .,Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA. .,Department of Bioinformatics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA.
| | - Xiaowei Zhan
- Department of Clinical Sciences, Quantitative Biomedical Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA. .,Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390, USA.
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43
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Lin IT, Chiou YM, Liang YC, Lin CN, Sun WSW, Li S, Chang CH, Syu WJ, Chen JW. Unique clustering genes in the bacterial chromosome affecting the type-III secretion of enterohaemorrhagic Escherichia coli. Microbiology (Reading) 2016; 162:1744-1754. [DOI: 10.1099/mic.0.000348] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Affiliation(s)
- I-Ting Lin
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Yi-Ming Chiou
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Yen-Chia Liang
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Ching-Nan Lin
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Wei-Sheng W. Sun
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Shiaowen Li
- Institute of Biomedical Informatics, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Chuan-Hsiung Chang
- Institute of Biomedical Informatics, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Wan-Jr Syu
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Jenn-Wei Chen
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC
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44
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Sirobhushanam S, Galva C, Sen S, Wilkinson BJ, Gatto C. Broad substrate specificity of phosphotransbutyrylase from Listeria monocytogenes: A potential participant in an alternative pathway for provision of acyl CoA precursors for fatty acid biosynthesis. BIOCHIMICA ET BIOPHYSICA ACTA 2016; 1861:1102-1110. [PMID: 27320015 PMCID: PMC4947441 DOI: 10.1016/j.bbalip.2016.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 05/20/2016] [Accepted: 06/10/2016] [Indexed: 12/22/2022]
Abstract
Listeria monocytogenes, the causative organism of the serious food-borne disease listeriosis, has a membrane abundant in branched-chain fatty acids (BCFAs). BCFAs are normally biosynthesized from branched-chain amino acids via the activity of branched chain α-keto acid dehydrogenase (Bkd), and disruption of this pathway results in reduced BCFA content in the membrane. Short branched-chain carboxylic acids (BCCAs) added as media supplements result in incorporation of BCFAs arising from the supplemented BCCAs in the membrane of L. monocytogenes bkd mutant MOR401. High concentrations of the supplements also effect similar changes in the membrane of the wild type organism with intact bkd. Such carboxylic acids clearly act as fatty acid precursors, and there must be an alternative pathway resulting in the formation of their CoA thioester derivatives. Candidates for this are the enzymes phosphotransbutyrylase (Ptb) and butyrate kinase (Buk), the products of the first two genes of the bkd operon. Ptb from L. monocytogenes exhibited broad substrate specificity, a strong preference for branched-chain substrates, a lack of activity with acetyl CoA and hexanoyl CoA, and strict chain length preference (C3-C5). Ptb catalysis involved ternary complex formation. Additionally, Ptb could utilize unnatural branched-chain substrates such as 2-ethylbutyryl CoA, albeit with lower efficiency, consistent with a potential involvement of this enzyme in the conversion of the carboxylic acid additives into CoA primers for BCFA biosynthesis.
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Affiliation(s)
| | - Charitha Galva
- School of Biological Sciences, Illinois State University, Normal, IL 61790, USA
| | - Suranjana Sen
- School of Biological Sciences, Illinois State University, Normal, IL 61790, USA
| | - Brian J Wilkinson
- School of Biological Sciences, Illinois State University, Normal, IL 61790, USA
| | - Craig Gatto
- School of Biological Sciences, Illinois State University, Normal, IL 61790, USA.
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45
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Lackraj T, Kim JI, Tran SL, Barnett Foster DE. Differential modulation of flagella expression in enterohaemorrhagic Escherichia coli O157: H7 by intestinal short-chain fatty acid mixes. MICROBIOLOGY-SGM 2016; 162:1761-1772. [PMID: 27535670 DOI: 10.1099/mic.0.000357] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
During passage through the gastrointestinal tract, enterohaemorrhagic Escherichia coli (EHEC) encounters numerous stresses, each producing unique antimicrobial conditions. Beyond surviving these stresses, EHEC may also use them as cues about the local microenvironment to modulate its virulence. Of particular interest is how exposure to changing concentrations of short-chain fatty acids (SCFAs) associated with passage through the small and large intestines affects EHEC virulence, as well as flagella expression and motility specifically. In this study, we investigate the impact of exposure to SCFA mixes simulating concentrations and compositions within the small and large intestines on EHEC flagella expression and function. Using a combination of DNA microarray, quantitative real-time PCR, immunoblot analysis, flow cytometry and motility assays, we show that there is a marked, significant upregulation of flagellar genes, the flagellar protein, FliC, and motility when EHEC is exposed to SCFA mixes representative of the small intestine. By contrast, when EHEC is exposed to SCFA mixes representative of the large intestine, there is a significant downregulation of flagellar genes, FliC and motility. Our results demonstrate that EHEC modulates flagella expression and motility in response to SCFAs, with differential responses associated with SCFA mixes typical of the small and large intestines. This research contributes to our understanding of how EHEC senses and responds to host environmental signals and the mechanisms it uses to successfully infect the human host. Significantly, it also suggests that EHEC is using this key gastrointestinal chemical signpost to cue changes in flagella expression and motility in different locations within the host intestinal tract.
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Affiliation(s)
- Tracy Lackraj
- Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada
| | - Jee In Kim
- Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada
| | - Seav-Ly Tran
- Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada
| | - Debora E Barnett Foster
- Faculty of Dentistry, University of Toronto, Toronto, ON, Canada.,Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada.,Program for Molecular Structure and Function, Research Institute, Hospital for Sick Children, Toronto, ON, Canada
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46
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Peng M, Biswas D. Short chain and polyunsaturated fatty acids in host gut health and foodborne bacterial pathogen inhibition. Crit Rev Food Sci Nutr 2016; 57:3987-4002. [DOI: 10.1080/10408398.2016.1203286] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Mengfei Peng
- Department of Animal and Avian Sciences, University of Maryland, College Park, Maryland, USA
- Biological Sciences Program Molecular and Cellular Biology Concentration, University of Maryland, College Park, Maryland, USA
| | - Debabrata Biswas
- Department of Animal and Avian Sciences, University of Maryland, College Park, Maryland, USA
- Biological Sciences Program Molecular and Cellular Biology Concentration, University of Maryland, College Park, Maryland, USA
- Center for Food Safety and Security Systems, University of Maryland, College Park, Maryland, USA
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47
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McKenney ES, Kendall MM. Microbiota and pathogen 'pas de deux': setting up and breaking down barriers to intestinal infection. Pathog Dis 2016; 74:ftw051. [PMID: 27252177 PMCID: PMC5985477 DOI: 10.1093/femspd/ftw051] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 02/04/2016] [Accepted: 05/24/2016] [Indexed: 02/07/2023] Open
Abstract
The gut microbiota plays essential roles in human health and disease. In this review, we focus on the role of the intestinal microbiota in promoting resistance to infection by bacterial pathogens as well as how pathogens overcome this barrier. We discuss how the resident microbiota restricts growth and colonization of invading pathogens by limiting availability of nutrients and through generation of a hostile environment. Additionally, we examine how microbiota-derived signaling molecules interfere with bacterial virulence. In turn, we discuss how pathogens exploit non-competitive metabolites to replicate in vivo as well as to precisely control virulence and cause disease. This bacterial two step of creating and overcoming challenges important in preventing and establishing infection highlights the complexities of elucidating interactions between the commensal bacteria and pathogens. Better understanding of microbiota-pathogen interplay will have significant implications for developing novel therapeutics to treat infectious diseases.
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Affiliation(s)
- Elizabeth S McKenney
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Melissa M Kendall
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
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Luzader DH, Kendall MM. Commensal 'trail of bread crumbs' provide pathogens with a map to the intestinal landscape. Curr Opin Microbiol 2015; 29:68-73. [PMID: 26707739 DOI: 10.1016/j.mib.2015.11.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 11/19/2015] [Accepted: 11/26/2015] [Indexed: 12/31/2022]
Abstract
Growth of a microorganism in a host is essential for infection, and bacterial pathogens have evolved to utilize specific metabolites to enhance replication in vivo. Now, emerging data demonstrate that pathogens rely on microbiota-derived metabolites as a form of bacterial-bacterial communication to gain information about location within a host and modify virulence gene expression accordingly. Thus, metabolite-sensing is critical for pathogens to establish infection. Here, we highlight recent examples of how the foodborne pathogen enterohemorrhagic Escherichia coli O157:H7 (EHEC) exploits microbiota-derived metabolites to recognize the host intestinal environment and control gene expression that results in controlled expression of virulence traits.
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Affiliation(s)
- Deborah H Luzader
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, 1340 Jefferson Park Ave., Charlottesville, VA 22908, USA
| | - Melissa M Kendall
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, 1340 Jefferson Park Ave., Charlottesville, VA 22908, USA.
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Chaban B, Hughes HV, Beeby M. The flagellum in bacterial pathogens: For motility and a whole lot more. Semin Cell Dev Biol 2015; 46:91-103. [DOI: 10.1016/j.semcdb.2015.10.032] [Citation(s) in RCA: 200] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 10/21/2015] [Accepted: 10/22/2015] [Indexed: 02/05/2023]
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Cameron EA, Sperandio V. Frenemies: Signaling and Nutritional Integration in Pathogen-Microbiota-Host Interactions. Cell Host Microbe 2015; 18:275-84. [PMID: 26355214 PMCID: PMC4567707 DOI: 10.1016/j.chom.2015.08.007] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The mammalian gastrointestinal (GI) microbiota is highly adapted to thrive in the GI environment and performs key functions related to host nutrition, physiology, development, immunity, and behavior. Successful host-bacterial associations require chemical signaling and optimal nutrient utilization and exchange. However, this important balance can be severely disrupted by environmental stimuli, with one of the most common insults upon the microbiota being infectious diseases. Although the microbiota acts as a barrier toward enteric pathogens, many enteric pathogens exploit signals and nutrients derived from both the microbiota and host to regulate their virulence programs. Here we review several signaling and nutrient recognition systems employed by GI pathogens to regulate growth and virulence. We discuss how shifts in the microbiota composition change host susceptibility to infection and how dietary changes or manipulation of the microbiota could potentially prevent and/or ameliorate GI infections.
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Affiliation(s)
- Elizabeth A Cameron
- Departments of Microbiology and Biochemistry, UT Southwestern Medical Center, Dallas, TX 75390-9048, USA
| | - Vanessa Sperandio
- Departments of Microbiology and Biochemistry, UT Southwestern Medical Center, Dallas, TX 75390-9048, USA.
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