1
|
Wang F, Sun H, Kang C, Yan J, Chen J, Feng X, Yang B. Genomic island-encoded regulatory proteins in enterohemorrhagic Escherichia coli O157:H7. Virulence 2024; 15:2313407. [PMID: 38357901 PMCID: PMC10877973 DOI: 10.1080/21505594.2024.2313407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 01/23/2024] [Indexed: 02/16/2024] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) is an important zoonotic pathogen that is a major cause of foodborne diseases in most developed and developing countries and can cause uncomplicated diarrhoea, haemorrhagic colitis, and haemolytic uraemic syndrome. O islands (OIs), which are unique genomic islands in EHEC O157:H7, are composed of 177 isolated genomic features and harbour 26% of the total genes that are absent in the non-pathogenic E. coli K-12 genome. In the last twenty years, many OI-encoded proteins have been characterized, including proteins regulating virulence, motility, and acid resistance. Given the critical role of regulatory proteins in the systematic and hierarchical regulation of bacterial biological processes, this review summarizes the OI-encoded regulatory proteins in EHEC O157:H7 characterized to date, emphasizing OI-encoded regulatory proteins for bacterial virulence, motility, and acid resistance. This summary will be significant for further exploration and understanding of the virulence and pathogenesis of EHEC O157:H7.
Collapse
Affiliation(s)
- Fang Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
- Intensive Care Unit, Shenzhen Institute of Translational Medicine, Health Science Center, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Hongmin Sun
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
| | - Chenbo Kang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
| | - Jun Yan
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
| | - Jingnan Chen
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
| | - Xuequan Feng
- Tianjin First Central Hospital, Nankai University, Tianjin, China
| | - Bin Yang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
| |
Collapse
|
2
|
Martins FH, Rosay T, Rajan A, Carter HE, Turocy T, Mejia A, Crawford JM, Maresso AW, Sperandio V. Enterococcus faecalis-derived adenine enhances enterohaemorrhagic Escherichia coli Type 3 Secretion System-dependent virulence. Nat Microbiol 2024; 9:2448-2461. [PMID: 38965331 DOI: 10.1038/s41564-024-01747-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 05/30/2024] [Indexed: 07/06/2024]
Abstract
Interactions between microbiota and enteric pathogens can promote colonization resistance or enhance pathogenesis. The pathobiont Enterococcus faecalis increases enterohaemorrhagic E. coli (EHEC) virulence by upregulating Type 3 Secretion System (T3SS) expression, effector translocation, and attaching and effacing (AE) lesion formation on enterocytes, but the mechanisms underlying this remain unknown. Using co-infection of organoids, metabolomics, supplementation experiments and bacterial genetics, here we show that co-culture of EHEC with E. faecalis increases the xanthine-hypoxanthine pathway activity and adenine biosynthesis. Adenine or E. faecalis promoted T3SS gene expression, while transcriptomics showed upregulation of adeP expression, which encodes an adenine importer. Mechanistically, adenine relieved High hemolysin activity (Hha)-dependent repression of T3SS gene expression in EHEC and promoted AE lesion formation in an AdeP-dependent manner. Microbiota-derived purines, such as adenine, support multiple beneficial host responses; however, our data show that this metabolite also increases EHEC virulence, highlighting the complexity of pathogen-microbiota-host interactions in the gut.
Collapse
Affiliation(s)
- Fernando H Martins
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Thibaut Rosay
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA
| | - Anubama Rajan
- TAILOR Labs, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Hannah E Carter
- TAILOR Labs, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Tayah Turocy
- Department of Chemistry, Yale University, New Haven, CT, USA
- Institute of Biomolecular Design and Discovery, Yale University, West Haven, CT, USA
| | - Andres Mejia
- Research Animal Resources and Compliance, University of Wisconsin-Madison, Madison, WI, USA
| | - Jason M Crawford
- Department of Chemistry, Yale University, New Haven, CT, USA
- Institute of Biomolecular Design and Discovery, Yale University, West Haven, CT, USA
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
| | - Anthony W Maresso
- TAILOR Labs, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Vanessa Sperandio
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA.
| |
Collapse
|
3
|
Beggs GA, Bassler BL. Phage small proteins play large roles in phage-bacterial interactions. Curr Opin Microbiol 2024; 80:102519. [PMID: 39047312 PMCID: PMC11323111 DOI: 10.1016/j.mib.2024.102519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2024] [Revised: 07/05/2024] [Accepted: 07/07/2024] [Indexed: 07/27/2024]
Abstract
Phages have wide influence on bacterial physiology, and likewise, bacterial processes impinge on phage biology. Key to these interactions are phage small proteins (<100 aa). Long underappreciated, recent work has revealed millions of phage small proteins, and increasingly, mechanisms by which they function to dictate phage and/or bacterial behavior and evolution. Here, we describe select phage small proteins that mediate phage-bacterial interactions by modulating phage lifestyle decision-making components or by altering host gene expression.
Collapse
Affiliation(s)
- Grace A Beggs
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Bonnie L Bassler
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.
| |
Collapse
|
4
|
Kalalah AA, Koenig SSK, Feng P, Bosilevac JM, Bono JL, Eppinger M. Pathogenomes of Shiga Toxin Positive and Negative Escherichia coli O157:H7 Strains TT12A and TT12B: Comprehensive Phylogenomic Analysis Using Closed Genomes. Microorganisms 2024; 12:699. [PMID: 38674643 PMCID: PMC11052207 DOI: 10.3390/microorganisms12040699] [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: 03/02/2024] [Revised: 03/18/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024] Open
Abstract
Shiga toxin-producing Escherichia coli are zoonotic pathogens that cause food-borne human disease. Among these, the O157:H7 serotype has evolved from an enteropathogenic O55:H7 ancestor through the displacement of the somatic gene cluster and recurrent toxigenic conversion by Shiga toxin-converting bacteriophages. However, atypical strains that lack the Shiga toxin, the characteristic virulence hallmark, are circulating in this lineage. For this study, we analyzed the pathogenome and virulence inventories of the stx+ strain, TT12A, isolated from a patient with hemorrhagic colitis, and its respective co-isolated stx- strain, TT12B. Sequencing the genomes to closure proved critical to the cataloguing of subtle strain differentiating sequence and structural polymorphisms at a high-level of phylogenetic accuracy and resolution. Phylogenomic profiling revealed SNP and MLST profiles similar to the near clonal outbreak isolates. Their prophage inventories, however, were notably different. The attenuated atypical non-shigatoxigenic status of TT12B is explained by the absence of both the ΦStx1a- and ΦStx2a-prophages carried by TT12A, and we also recorded further alterations in the non-Stx prophage complement. Phenotypic characterization indicated that culture growth was directly impacted by the strains' distinct lytic phage complement. Altogether, our phylogenomic and phenotypic analyses show that these intimately related isogenic strains are on divergent Stx(+/stx-) evolutionary paths.
Collapse
Affiliation(s)
- Anwar A. Kalalah
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX 78249, USA
- South Texas Center for Emerging Infectious Diseases (STCEID), San Antonio, TX 78249, USA
| | - Sara S. K. Koenig
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX 78249, USA
- South Texas Center for Emerging Infectious Diseases (STCEID), San Antonio, TX 78249, USA
| | - Peter Feng
- U.S. Food and Drug Administration (FDA), College Park, MD 20740, USA
| | - Joseph M. Bosilevac
- U.S. Department of Agriculture (USDA), Agricultural Research Service (ARS), U.S. Meat Animal Research Center, Clay Center, NE 68933, USA
| | - James L. Bono
- U.S. Department of Agriculture (USDA), Agricultural Research Service (ARS), U.S. Meat Animal Research Center, Clay Center, NE 68933, USA
| | - Mark Eppinger
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX 78249, USA
- South Texas Center for Emerging Infectious Diseases (STCEID), San Antonio, TX 78249, USA
| |
Collapse
|
5
|
Gong C, Chakraborty D, Koudelka GB. A prophage encoded ribosomal RNA methyltransferase regulates the virulence of Shiga-toxin-producing Escherichia coli (STEC). Nucleic Acids Res 2024; 52:856-871. [PMID: 38084890 PMCID: PMC10810198 DOI: 10.1093/nar/gkad1150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 11/09/2023] [Accepted: 11/14/2023] [Indexed: 01/26/2024] Open
Abstract
Shiga toxin (Stx) released by Shiga toxin producing Escherichia coli (STEC) causes life-threatening illness. Its production and release require induction of Stx-encoding prophage resident within the STEC genome. We identified two different STEC strains, PA2 and PA8, bearing Stx-encoding prophage whose sequences primarily differ by the position of an IS629 insertion element, yet differ in their abilities to kill eukaryotic cells and whose prophages differ in their spontaneous induction frequencies. The IS629 element in ϕPA2, disrupts an ORF predicted to encode a DNA adenine methyltransferase, whereas in ϕPA8, this element lies in an intergenic region. Introducing a plasmid expressing the methyltransferase gene product into ϕPA2 bearing-strains increases both the prophage spontaneous induction frequency and virulence to those exhibited by ϕPA8 bearing-strains. However, a plasmid bearing mutations predicted to disrupt the putative active site of the methyltransferase does not complement either of these defects. When complexed with a second protein, the methyltransferase holoenzyme preferentially uses 16S rRNA as a substrate. The second subunit is responsible for directing the preferential methylation of rRNA. Together these findings reveal a previously unrecognized role for rRNA methylation in regulating induction of Stx-encoding prophage.
Collapse
Affiliation(s)
- Chen Gong
- Department of Biological Sciences University at Buffalo, Buffalo, NY 14260, USA
| | | | - Gerald B Koudelka
- Department of Biological Sciences University at Buffalo, Buffalo, NY 14260, USA
| |
Collapse
|
6
|
Mahmud MR, Tamanna SK, Akter S, Mazumder L, Akter S, Hasan MR, Acharjee M, Esti IZ, Islam MS, Shihab MMR, Nahian M, Gulshan R, Naser S, Pirttilä AM. Role of bacteriophages in shaping gut microbial community. Gut Microbes 2024; 16:2390720. [PMID: 39167701 PMCID: PMC11340752 DOI: 10.1080/19490976.2024.2390720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 08/05/2024] [Accepted: 08/06/2024] [Indexed: 08/23/2024] Open
Abstract
Phages are the most diversified and dominant members of the gut virobiota. They play a crucial role in shaping the structure and function of the gut microbial community and consequently the health of humans and animals. Phages are found mainly in the mucus, from where they can translocate to the intestinal organs and act as a modulator of gut microbiota. Understanding the vital role of phages in regulating the composition of intestinal microbiota and influencing human and animal health is an emerging area of research. The relevance of phages in the gut ecosystem is supported by substantial evidence, but the importance of phages in shaping the gut microbiota remains unclear. Although information regarding general phage ecology and development has accumulated, detailed knowledge on phage-gut microbe and phage-human interactions is lacking, and the information on the effects of phage therapy in humans remains ambiguous. In this review, we systematically assess the existing data on the structure and ecology of phages in the human and animal gut environments, their development, possible interaction, and subsequent impact on the gut ecosystem dynamics. We discuss the potential mechanisms of prophage activation and the subsequent modulation of gut bacteria. We also review the link between phages and the immune system to collect evidence on the effect of phages on shaping the gut microbial composition. Our review will improve understanding on the influence of phages in regulating the gut microbiota and the immune system and facilitate the development of phage-based therapies for maintaining a healthy and balanced gut microbiota.
Collapse
Affiliation(s)
- Md. Rayhan Mahmud
- Department of Production Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | | | - Sharmin Akter
- Department of Microbiology, Jagannath University, Dhaka, Bangladesh
| | - Lincon Mazumder
- Department of Microbiology, Jagannath University, Dhaka, Bangladesh
- Department of Biology, Texas A&M University, College Station, TX, USA
| | - Sumona Akter
- Department of Microbiology, Jagannath University, Dhaka, Bangladesh
| | | | - Mrityunjoy Acharjee
- Department of Microbiology, Stamford University Bangladesh, Dhaka, Bangladesh
| | - Israt Zahan Esti
- Department of Microbiology, Jagannath University, Dhaka, Bangladesh
- Department of Molecular Systems Biology, Faculty of Technology, University of Turku, Turku, Finland
| | - Md. Saidul Islam
- Department of Microbiology, Jagannath University, Dhaka, Bangladesh
| | | | - Md. Nahian
- Department of Microbiology, Jagannath University, Dhaka, Bangladesh
| | - Rubaiya Gulshan
- Department of Microbiology, Jagannath University, Dhaka, Bangladesh
| | - Sadia Naser
- Department of Microbiology, Jagannath University, Dhaka, Bangladesh
| | | |
Collapse
|
7
|
Mlera L, Collins-McMillen D, Zeltzer S, Buehler JC, Moy M, Zarrella K, Caviness K, Cicchini L, Tafoya DJ, Goodrum F. Liver X Receptor-Inducible Host E3 Ligase IDOL Targets a Human Cytomegalovirus Reactivation Determinant. J Virol 2023; 97:e0075823. [PMID: 37338407 PMCID: PMC10373547 DOI: 10.1128/jvi.00758-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 05/30/2023] [Indexed: 06/21/2023] Open
Abstract
Liver X receptor (LXR) signaling broadly restricts virus replication; however, the mechanisms of restriction are poorly defined. Here, we demonstrate that the cellular E3 ligase LXR-inducible degrader of low-density lipoprotein receptor (IDOL) targets the human cytomegalovirus (HMCV) UL136p33 protein for turnover. UL136 encodes multiple proteins that differentially impact latency and reactivation. UL136p33 is a determinant of reactivation. UL136p33 is targeted for rapid turnover by the proteasome, and its stabilization by mutation of lysine residues to arginine results in a failure to quiet replication for latency. We show that IDOL targets UL136p33 for turnover but not the stabilized variant. IDOL is highly expressed in undifferentiated hematopoietic cells where HCMV establishes latency but is sharply downregulated upon differentiation, a stimulus for reactivation. We hypothesize that IDOL maintains low levels of UL136p33 for the establishment of latency. Consistent with this hypothesis, knockdown of IDOL impacts viral gene expression in wild-type (WT) HCMV infection but not in infection where UL136p33 has been stabilized. Furthermore, the induction of LXR signaling restricts WT HCMV reactivation from latency but does not affect the replication of a recombinant virus expressing a stabilized variant of UL136p33. This work establishes the UL136p33-IDOL interaction as a key regulator of the bistable switch between latency and reactivation. It further suggests a model whereby a key viral determinant of HCMV reactivation is regulated by a host E3 ligase and acts as a sensor at the tipping point between the decision to maintain the latent state or exit latency for reactivation. IMPORTANCE Herpesviruses establish lifelong latent infections, which pose an important risk for disease particularly in the immunocompromised. Our work is focused on the betaherpesvirus human cytomegalovirus (HCMV) that latently infects the majority of the population worldwide. Defining the mechanisms by which HCMV establishes latency or reactivates from latency is important for controlling viral disease. Here, we demonstrate that the cellular inducible degrader of low-density lipoprotein receptor (IDOL) targets a HCMV determinant of reactivation for degradation. The instability of this determinant is important for the establishment of latency. This work defines a pivotal virus-host interaction that allows HCMV to sense changes in host biology to navigate decisions to establish latency or to replicate.
Collapse
Affiliation(s)
- Luwanika Mlera
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
| | - Donna Collins-McMillen
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
| | - Sebastian Zeltzer
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
| | - Jason C. Buehler
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
| | - Melissa Moy
- Graduate Interdisciplinary Program in Cancer Biology, University of Arizona, Tucson, Arizona, USA
| | - Kristen Zarrella
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
| | - Katie Caviness
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
- Graduate Interdisciplinary Program in Genetics, University of Arizona, Tucson, Arizona, USA
| | - Louis Cicchini
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, USA
| | - David J. Tafoya
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
| | - Felicia Goodrum
- Department of Immunobiology, University of Arizona, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
- Graduate Interdisciplinary Program in Cancer Biology, University of Arizona, Tucson, Arizona, USA
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, USA
| |
Collapse
|
8
|
Chen GY, Thorup NR, Miller AJ, Li YC, Ayres JS. Cooperation between physiological defenses and immune resistance produces asymptomatic carriage of a lethal bacterial pathogen. SCIENCE ADVANCES 2023; 9:eadg8719. [PMID: 37352357 PMCID: PMC10289649 DOI: 10.1126/sciadv.adg8719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 05/18/2023] [Indexed: 06/25/2023]
Abstract
Animals evolved two defense strategies to survive infections. Antagonistic strategies include immune resistance mechanisms that operate to kill invading pathogens. Cooperative or physiological defenses mediate host adaptation to the infected state, limiting physiological damage and disease, without killing the pathogen, and have been shown to cause asymptomatic carriage and transmission of lethal pathogens. Here, we demonstrate that physiological defenses cooperate with the adaptive immune response to generate long-term asymptomatic carriage of the lethal enteric murine pathogen, Citrobacter rodentium. Asymptomatic carriage of genetically virulent C. rodentium provided immune resistance against subsequent infections. Immune protection was dependent on systemic antibody responses and pathogen virulence behavior rather than the recognition of specific virulent antigens. Last, we demonstrate that an avirulent strain of C. rodentium in the field has background mutations in genes that are important for LPS structure. Our work reveals insight into how asymptomatic infections can arise mechanistically with immune resistance, mediating exclusion of phenotypically virulent enteric pathogen to promote asymptomatic carriage.
Collapse
Affiliation(s)
- Grischa Y. Chen
- Molecular and Systems Physiology Lab, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
- NOMIS Center for Immunobiology and Microbial Pathogenesis, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Natalia R. Thorup
- Molecular and Systems Physiology Lab, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
- NOMIS Center for Immunobiology and Microbial Pathogenesis, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Abigail J. Miller
- Molecular and Systems Physiology Lab, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
- NOMIS Center for Immunobiology and Microbial Pathogenesis, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Yao-Cheng Li
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Janelle S. Ayres
- Molecular and Systems Physiology Lab, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
- NOMIS Center for Immunobiology and Microbial Pathogenesis, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| |
Collapse
|
9
|
Chen GY, Thorup NR, Miller AJ, Li YC, Ayres JS. Cooperation between physiological defenses and immune resistance produces asymptomatic carriage of a lethal bacterial pathogen. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.22.525099. [PMID: 36711884 PMCID: PMC9882269 DOI: 10.1101/2023.01.22.525099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Animals have evolved two defense strategies to survive infections. Antagonistic strategies include mechanisms of immune resistance that operate to sense and kill invading pathogens. Cooperative or physiological defenses mediate host adaptation to the infected state, limiting physiological damage and disease, without killing the pathogen, and have been shown to cause asymptomatic carriage and transmission of lethal pathogens. Here we demonstrate that physiological defenses cooperate with the adaptive immune response to generate long-term asymptomatic carriage of the lethal enteric murine pathogen, Citrobacter rodentium. Asymptomatic carriage of genetically virulent C. rodentium provided immune resistance against subsequent infections. Host immune protection was dependent on systemic antibody responses and pathogen virulence behavior, rather than the recognition of specific virulent factor antigens. Finally, we demonstrate that an avirulent strain of C. rodentium in the field has background mutations in two genes that are important for LPS structure. Our work reveals novel insight into how asymptomatic infections can arise mechanistically with immune resistance, mediating exclusion of phenotypically virulent enteric pathogen to promote asymptomatic carriage.
Collapse
Affiliation(s)
- Grischa Y. Chen
- Molecular and Systems Physiology Lab, The Salk Institute for Biological Studies, La Jolla, CA 92037
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037
- NOMIS Center for Immunobiology and Microbial Pathogenesis, The Salk Institute for Biological Studies, La Jolla, CA 92037
| | - Natalia R. Thorup
- Molecular and Systems Physiology Lab, The Salk Institute for Biological Studies, La Jolla, CA 92037
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037
- NOMIS Center for Immunobiology and Microbial Pathogenesis, The Salk Institute for Biological Studies, La Jolla, CA 92037
| | - Abigail J. Miller
- Molecular and Systems Physiology Lab, The Salk Institute for Biological Studies, La Jolla, CA 92037
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037
- NOMIS Center for Immunobiology and Microbial Pathogenesis, The Salk Institute for Biological Studies, La Jolla, CA 92037
| | - Yao-Cheng Li
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037
| | - Janelle S. Ayres
- Molecular and Systems Physiology Lab, The Salk Institute for Biological Studies, La Jolla, CA 92037
- Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037
- NOMIS Center for Immunobiology and Microbial Pathogenesis, The Salk Institute for Biological Studies, La Jolla, CA 92037
| |
Collapse
|
10
|
Jaswal K, Todd OA, Behnsen J. Neglected gut microbiome: interactions of the non-bacterial gut microbiota with enteric pathogens. Gut Microbes 2023; 15:2226916. [PMID: 37365731 DOI: 10.1080/19490976.2023.2226916] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 06/12/2023] [Accepted: 06/14/2023] [Indexed: 06/28/2023] Open
Abstract
A diverse array of commensal microorganisms inhabits the human intestinal tract. The most abundant and most studied members of this microbial community are undoubtedly bacteria. Their important role in gut physiology, defense against pathogens, and immune system education has been well documented over the last decades. However, the gut microbiome is not restricted to bacteria. It encompasses the entire breadth of microbial life: viruses, archaea, fungi, protists, and parasitic worms can also be found in the gut. While less studied than bacteria, their divergent but important roles during health and disease have become increasingly more appreciated. This review focuses on these understudied members of the gut microbiome. We will detail the composition and development of these microbial communities and will specifically highlight their functional interactions with enteric pathogens, such as species of the family Enterobacteriaceae. The interactions can be direct through physical interactions, or indirect through secreted metabolites or modulation of the immune response. We will present general concepts and specific examples of how non-bacterial gut communities modulate bacterial pathogenesis and present an outlook for future gut microbiome research that includes these communities.
Collapse
Affiliation(s)
- Kanchan Jaswal
- Department of Microbiology and Immunology, University of Illinois Chicago, Chicago, IL, USA
| | - Olivia A Todd
- Department of Microbiology and Immunology, University of Illinois Chicago, Chicago, IL, USA
| | - Judith Behnsen
- Department of Microbiology and Immunology, University of Illinois Chicago, Chicago, IL, USA
| |
Collapse
|
11
|
When bacteria are phage playgrounds: interactions between viruses, cells, and mobile genetic elements. Curr Opin Microbiol 2022; 70:102230. [PMID: 36335712 DOI: 10.1016/j.mib.2022.102230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 09/23/2022] [Accepted: 10/06/2022] [Indexed: 11/06/2022]
Abstract
Studies of viral adaptation have focused on the selective pressures imposed by hosts. However, there is increasing evidence that interactions between viruses, cells, and other mobile genetic elements are determinant to the success of infections. These interactions are often associated with antagonism and competition, but sometimes involve cooperation or parasitism. We describe two key types of interactions - defense systems and genetic regulation - that allow the partners of the interaction to destroy or control the others. These interactions evolve rapidly by genetic exchanges, including among competing partners. They are sometimes followed by functional diversification. Gene exchanges also facilitate the emergence of cross-talk between elements in the same bacterium. In the end, these processes produce multilayered networks of interactions that shape the outcome of viral infections.
Collapse
|
12
|
Allué-Guardia A, Koenig SSK, Martinez RA, Rodriguez AL, Bosilevac JM, Feng† P, Eppinger M. Pathogenomes and variations in Shiga toxin production among geographically distinct clones of Escherichia coli O113:H21. Microb Genom 2022; 8. [PMID: 35394418 PMCID: PMC9453080 DOI: 10.1099/mgen.0.000796] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Infections with globally disseminated Shiga toxin-producing Escherichia coli (STEC) of the O113:H21 serotype can progress to severe clinical complications, such as hemolytic uremic syndrome (HUS). Two phylogeographically distinct clonal complexes have been established by multi locus sequence typing (MLST). Infections with ST-820 isolates circulating exclusively in Australia have caused severe human disease, such as HUS. Conversely, ST-223 isolates prevalent in the US and outside Australia seem to rarely cause severe human disease but are frequent contaminants. Following a genomic epidemiology approach, we wanted to gain insights into the underlying cause for this disparity. We examined the plasticity in the genome make-up and Shiga toxin production in a collection of 20 ST-820 and ST-223 strains isolated from produce, the bovine reservoir, and clinical cases. STEC are notorious for assembly into fragmented draft sequences when using short-read sequencing technologies due to the extensive and partly homologous phage complement. The application of long-read technology (LRT) sequencing yielded closed reference chromosomes and plasmids for two representative ST-820 and ST-223 strains. The established high-resolution framework, based on whole genome alignments, single nucleotide polymorphism (SNP)-typing and MLST, includes the chromosomes and plasmids of other publicly available O113:H21 sequences and allowed us to refine the phylogeographical boundaries of ST-820 and ST-223 complex isolates and to further identify a historic non-shigatoxigenic strain from Mexico as a quasi-intermediate. Plasmid comparison revealed strong correlations between the strains' featured pO113 plasmid genotypes and chromosomally inferred ST, which suggests coevolution of the chromosome and virulence plasmids. Our pathogenicity assessment revealed statistically significant differences in the Stx2a-production capabilities of ST-820 as compared to ST-223 strains under RecA-induced Stx phage mobilization, a condition that mimics Stx-phage induction. These observations suggest that ST-820 strains may confer an increased pathogenic potential in line with the strain-associated epidemiological metadata. Still, some of the tested ST-223 cultures sourced from contaminated produce or the bovine reservoir also produced Stx at levels comparable to those of ST-820 isolates, which calls for awareness and for continued surveillance of this lineage.
Collapse
Affiliation(s)
- Anna Allué-Guardia
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX, USA
- South Texas Center for Emerging Infectious Diseases (STCEID), San Antonio, TX, USA
| | - Sara S. K. Koenig
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX, USA
- South Texas Center for Emerging Infectious Diseases (STCEID), San Antonio, TX, USA
| | - Ricardo A. Martinez
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX, USA
- South Texas Center for Emerging Infectious Diseases (STCEID), San Antonio, TX, USA
| | - Armando L. Rodriguez
- University of Texas at San Antonio, Research Computing Support Group, San Antonio, TX, USA
| | - Joseph M. Bosilevac
- U.S. Department of Agriculture (USDA), Agricultural Research Service (ARS), Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, NE, USA
| | - Peter Feng†
- U.S. Food and Drug Administration (FDA), College Park, MD, USA
| | - Mark Eppinger
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX, USA
- South Texas Center for Emerging Infectious Diseases (STCEID), San Antonio, TX, USA
- *Correspondence: Mark Eppinger,
| |
Collapse
|
13
|
Sjahriani T, Wasito EB, Tyasningsih W. The Analysis of OmpA and Rz/Rz1 of Lytic Bacteriophage from Surabaya, Indonesia. SCIENTIFICA 2021; 2021:7494144. [PMID: 35096434 PMCID: PMC8794686 DOI: 10.1155/2021/7494144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 11/28/2021] [Accepted: 12/01/2021] [Indexed: 06/14/2023]
Abstract
A good strategy to conquer the Escherichia coli-cause food-borne disease could be bacteriophages. Porins are a type of β-barrel proteins with diffuse channels and OmpA, which has a role in hydrophilic transport, is the most frequent porin in E. coli; it was also chosen as the potential receptor of the phage. And the Rz/Rz1 was engaged in the breakup of the host bacterial external membrane. This study aimed to analyze the amino acid of OmpA and Rz/Rz1 of lytic bacteriophage from Surabaya, Indonesia. This study employed a sample of 8 bacteriophages from the previous study. The OmpA analysis method was mass spectrometry. Rz/Rz1 was analyzed using PCR, DNA sequencing, Expasy Translation, and Expasy ProtParam. The result obtained 10% to 29% sequence coverage of OmpA, carrying the ligand-binding site. The Rz/Rz1 gene shares a high percentage of 97.04% to 98.89% identities with the Siphoviridae isolate ctTwQ4, partial genome, and Myoviridae isolate cthRA4, partial genome. The Mann-Whitney statistical tests indicate the significant differences between Alanine, Aspartate, Glycine, Proline, Serine (p=0.011), Asparagine, Cysteine (p=0.009), Isoleucine (p=0.043), Lysine (p=0.034), Methionine (p=0.001), Threonine (p=0.018), and Tryptophan (p=0.007) of OmpA and Rz/Rz1. The conclusion obtained from this study is the fact that OmpA acts as Phage 1, Phage 2, Phage 3, Phage 5, and Phage 6 receptors for its peptide composition comprising the ligand binding site, and Rz/Rz1 participates in host bacteria lysis.
Collapse
Affiliation(s)
- Tessa Sjahriani
- Doctoral Program, Faculty of Medicine, Universitas Airlangga, Dr. Moestopo Road No. 47, Surabaya 60285, Indonesia
- Department of Microbiology, Faculty of Medicine, Universitas Malahayati, Pramuka Road No. 27, Bandar Lampung 35158, Indonesia
| | - Eddy Bagus Wasito
- Department of Microbiology, Faculty of Medicine, Universitas Airlangga, Dr. Moestopo Road No. 47, Surabaya 60285, Indonesia
| | - Wiwiek Tyasningsih
- Department of Microbiology, Faculty of Veterinary Medicine, Universitas Airlangga, C Campus, Mulyorejo Road, Surabaya 60115, Indonesia
| |
Collapse
|
14
|
Schroven K, Aertsen A, Lavigne R. Bacteriophages as drivers of bacterial virulence and their potential for biotechnological exploitation. FEMS Microbiol Rev 2021; 45:5902850. [PMID: 32897318 DOI: 10.1093/femsre/fuaa041] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 09/03/2020] [Indexed: 12/20/2022] Open
Abstract
Bacteria-infecting viruses (phages) and their hosts maintain an ancient and complex relationship. Bacterial predation by lytic phages drives an ongoing phage-host arms race, whereas temperate phages initiate mutualistic relationships with their hosts upon lysogenization as prophages. In human pathogens, these prophages impact bacterial virulence in distinct ways: by secretion of phage-encoded toxins, modulation of the bacterial envelope, mediation of bacterial infectivity and the control of bacterial cell regulation. This review builds the argument that virulence-influencing prophages hold extensive, unexplored potential for biotechnology. More specifically, it highlights the development potential of novel therapies against infectious diseases, to address the current antibiotic resistance crisis. First, designer bacteriophages may serve to deliver genes encoding cargo proteins which repress bacterial virulence. Secondly, one may develop small molecules mimicking phage-derived proteins targeting central regulators of bacterial virulence. Thirdly, bacteria equipped with phage-derived synthetic circuits which modulate key virulence factors could serve as vaccine candidates to prevent bacterial infections. The development and exploitation of such antibacterial strategies will depend on the discovery of other prophage-derived, virulence control mechanisms and, more generally, on the dissection of the mutualistic relationship between temperate phages and bacteria, as well as on continuing developments in the synthetic biology field.
Collapse
Affiliation(s)
- Kaat Schroven
- Laboratory of Gene Technology, KU Leuven, Kasteelpark Arenberg 21, 3001 Leuven, Belgium
| | - Abram Aertsen
- Laboratory of Food Microbiology, KU Leuven, Kasteelpark Arenberg 23, 3001 Leuven, Belgium
| | - Rob Lavigne
- Laboratory of Gene Technology, KU Leuven, Kasteelpark Arenberg 21, 3001 Leuven, Belgium
| |
Collapse
|
15
|
Ismail MH, Michie KA, Goh YF, Noorian P, Kjelleberg S, Duggin IG, McDougald D, Rice SA. The Repressor C Protein, Pf4r, Controls Superinfection of Pseudomonas aeruginosa PAO1 by the Pf4 Filamentous Phage and Regulates Host Gene Expression. Viruses 2021; 13:1614. [PMID: 34452479 PMCID: PMC8402870 DOI: 10.3390/v13081614] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 08/09/2021] [Accepted: 08/13/2021] [Indexed: 12/17/2022] Open
Abstract
It has been shown that the filamentous phage, Pf4, plays an important role in biofilm development, stress tolerance, genetic variant formation and virulence in Pseudomonas aeruginosa PAO1. These behaviours are linked to the appearance of superinfective phage variants. Here, we have investigated the molecular mechanism of superinfection as well as how the Pf4 phage can control host gene expression to modulate host behaviours. Pf4 exists as a prophage in PAO1 and encodes a homologue of the P2 phage repressor C and was recently named Pf4r. Through a combination of molecular techniques, ChIPseq and transcriptomic analyses, we show a critical site in repressor C (Pf4r) where a mutation in the site, 788799A>G (Ser4Pro), causes Pf4r to lose its function as the immunity factor against reinfection by Pf4. X-ray crystal structure analysis shows that Pf4r forms symmetric homo-dimers homologous to the E.coli bacteriophage P2 RepC protein. A mutation, Pf4r*, associated with the superinfective Pf4r variant, found at the dimer interface, suggests dimer formation may be disrupted, which derepresses phage replication. This is supported by multi-angle light scattering (MALS) analysis, where the Pf4r* protein only forms monomers. The loss of dimerisation also explains the loss of Pf4r's immunity function. Phenotypic assays showed that Pf4r increased LasB activity and was also associated with a slight increase in the percentage of morphotypic variants. ChIPseq and transcriptomic analyses suggest that Pf4r also likely functions as a transcriptional regulator for other host genes. Collectively, these data suggest the mechanism by which filamentous phages play such an important role in P. aeruginosa biofilm development.
Collapse
Affiliation(s)
- Muhammad Hafiz Ismail
- Singapore Centre for Environmental Life Sciences Engineering, Singapore 637551, Singapore; (M.H.I.); (Y.F.G.); (S.K.); (D.M.)
- The School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Katharine A. Michie
- Structural Biology Facility, Mark Wainwright Analytical Centre, The University of New South Wales, Sydney, NSW 2052, Australia;
| | - Yu Fen Goh
- Singapore Centre for Environmental Life Sciences Engineering, Singapore 637551, Singapore; (M.H.I.); (Y.F.G.); (S.K.); (D.M.)
| | - Parisa Noorian
- The iThree Institute, The University of Technology Sydney, Sydney, NSW 2007, Australia; (P.N.); (I.G.D.)
| | - Staffan Kjelleberg
- Singapore Centre for Environmental Life Sciences Engineering, Singapore 637551, Singapore; (M.H.I.); (Y.F.G.); (S.K.); (D.M.)
- The School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Iain G. Duggin
- The iThree Institute, The University of Technology Sydney, Sydney, NSW 2007, Australia; (P.N.); (I.G.D.)
| | - Diane McDougald
- Singapore Centre for Environmental Life Sciences Engineering, Singapore 637551, Singapore; (M.H.I.); (Y.F.G.); (S.K.); (D.M.)
- The iThree Institute, The University of Technology Sydney, Sydney, NSW 2007, Australia; (P.N.); (I.G.D.)
| | - Scott A. Rice
- Singapore Centre for Environmental Life Sciences Engineering, Singapore 637551, Singapore; (M.H.I.); (Y.F.G.); (S.K.); (D.M.)
- The School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
- The iThree Institute, The University of Technology Sydney, Sydney, NSW 2007, Australia; (P.N.); (I.G.D.)
| |
Collapse
|
16
|
Sklyar T, Kurahina N, Lavrentieva K, Burlaka V, Lykholat T, Lykholat O. Autonomic (Mobile) Genetic Elements of Bacteria and Their Hierarchy. CYTOL GENET+ 2021. [DOI: 10.3103/s0095452721030099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
17
|
Pinto G, Sampaio M, Dias O, Almeida C, Azeredo J, Oliveira H. Insights into the genome architecture and evolution of Shiga toxin encoding bacteriophages of Escherichia coli. BMC Genomics 2021; 22:366. [PMID: 34011288 PMCID: PMC8136144 DOI: 10.1186/s12864-021-07685-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 05/07/2021] [Indexed: 11/18/2022] Open
Abstract
Background A total of 179 Shiga toxin-producing Escherichia coli (STEC) complete genomes were analyzed in terms of serotypes, prophage coding regions, and stx gene variants and their distribution. We further examined the genetic diversity of Stx-converting phage genomes (Stx phages), focusing on the lysis-lysogeny decision and lytic cassettes. Results We show that most STEC isolates belong to non-O157 serotypes (73 %), regardless the sources and geographical regions. While the majority of STEC genomes contain a single stx gene (61 %), strains containing two (35 %), three (3 %) and four (1 %) stx genes were also found, being stx2 the most prevalent gene variant. Their location is exclusively found in intact prophage regions, indicating that they are phage-borne. We further demonstrate that Stx phages can be grouped into four clusters (A, B, C and D), three subclusters (A1, A2 and A3) and one singleton, based on their shared gene content. This cluster distribution is in good agreement with their predicted virion morphologies. Stx phage genomes are highly diverse with a vast number of 1,838 gene phamilies (phams) of related sequences (of which 677 are orphams i.e. unique genes) and, although having high mosaicism, they are generally organized into three major transcripts. While the mechanisms that guide lysis–lysogeny decision are complex, there is a strong selective pressure to maintain the stx genes location close to the lytic cassette composed of predicted SAR-endolysin and pin-holin lytic proteins. The evolution of STEC Stx phages seems to be strongly related to acquiring genetic material, probably from horizontal gene transfer events. Conclusions This work provides novel insights on the genetic structure of Stx phages, showing a high genetic diversity throughout the genomes, where the various lysis-lysogeny regulatory systems are in contrast with an uncommon, but conserved, lytic system always adjacent to stx genes. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07685-0.
Collapse
Affiliation(s)
- Graça Pinto
- CEB - Centre of Biological Engineering, University of Minho, 4710-057, Braga, Portugal.,INIAV, IP-National Institute for Agrarian and Veterinary Research, Rua dos Lagidos, Lugar da Madalena, Vairão, Vila do Conde, Portugal
| | - Marta Sampaio
- CEB - Centre of Biological Engineering, University of Minho, 4710-057, Braga, Portugal
| | - Oscar Dias
- CEB - Centre of Biological Engineering, University of Minho, 4710-057, Braga, Portugal
| | - Carina Almeida
- INIAV, IP-National Institute for Agrarian and Veterinary Research, Rua dos Lagidos, Lugar da Madalena, Vairão, Vila do Conde, Portugal
| | - Joana Azeredo
- CEB - Centre of Biological Engineering, University of Minho, 4710-057, Braga, Portugal.
| | - Hugo Oliveira
- CEB - Centre of Biological Engineering, University of Minho, 4710-057, Braga, Portugal.
| |
Collapse
|
18
|
Campbell DE, Ly LK, Ridlon JM, Hsiao A, Whitaker RJ, Degnan PH. Infection with Bacteroides Phage BV01 Alters the Host Transcriptome and Bile Acid Metabolism in a Common Human Gut Microbe. Cell Rep 2021; 32:108142. [PMID: 32937127 PMCID: PMC8354205 DOI: 10.1016/j.celrep.2020.108142] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 07/07/2020] [Accepted: 08/21/2020] [Indexed: 12/16/2022] Open
Abstract
Gut-associated phages are hypothesized to alter the abundance and activity of their bacterial hosts, contributing to human health and disease. Although temperate phages constitute a significant fraction of the gut virome, the effects of lysogenic infection are underexplored. We report that the temperate phage, Bacteroides phage BV01, broadly alters its host's transcriptome, the prominent human gut symbiont Bacteroides vulgatus. This alteration occurs through phage-induced repression of a tryptophan-rich sensory protein (TspO) and represses bile acid deconjugation. Because microbially modified bile acids are important signals for the mammalian host, this is a mechanism by which a phage may influence mammalian phenotypes. Furthermore, BV01 and its relatives in the proposed phage family Salyersviridae are ubiquitous in human gut metagenomes, infecting a broad range of Bacteroides hosts. These results demonstrate the complexity of phage-bacteria-mammal relationships and emphasize a need to better understand the role of temperate phages in the gut microbiome.
Collapse
Affiliation(s)
| | - Lindsey K Ly
- Division of Nutritional Sciences, University of Illinois, Urbana, IL 61801, USA; Department of Animal Sciences, University of Illinois, Urbana, IL 61801, USA
| | - Jason M Ridlon
- Division of Nutritional Sciences, University of Illinois, Urbana, IL 61801, USA; Department of Animal Sciences, University of Illinois, Urbana, IL 61801, USA; Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA
| | - Ansel Hsiao
- Department of Microbiology and Plant Pathology, University of California, Riverside, Riverside, CA 92521, USA
| | - Rachel J Whitaker
- Department of Microbiology, University of Illinois, Urbana, IL 61801, USA; Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA
| | - Patrick H Degnan
- Department of Microbiology and Plant Pathology, University of California, Riverside, Riverside, CA 92521, USA.
| |
Collapse
|
19
|
Rodríguez-Rubio L, Haarmann N, Schwidder M, Muniesa M, Schmidt H. Bacteriophages of Shiga Toxin-Producing Escherichia coli and Their Contribution to Pathogenicity. Pathogens 2021; 10:404. [PMID: 33805526 PMCID: PMC8065619 DOI: 10.3390/pathogens10040404] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/18/2021] [Accepted: 03/24/2021] [Indexed: 12/25/2022] Open
Abstract
Shiga toxins (Stx) of Shiga toxin-producing Escherichia coli (STEC) are generally encoded in the genome of lambdoid bacteriophages, which spend the most time of their life cycle integrated as prophages in specific sites of the bacterial chromosome. Upon spontaneous induction or induction by chemical or physical stimuli, the stx genes are co-transcribed together with the late phase genes of the prophages. After being assembled in the cytoplasm, and after host cell lysis, mature bacteriophage particles are released into the environment, together with Stx. As members of the group of lambdoid phages, Stx phages share many genetic features with the archetypical temperate phage Lambda, but are heterogeneous in their DNA sequences due to frequent recombination events. In addition to Stx phages, the genome of pathogenic STEC bacteria may contain numerous prophages, which are either cryptic or functional. These prophages may carry foreign genes, some of them related to virulence, besides those necessary for the phage life cycle. Since the production of one or more Stx is considered the major pathogenicity factor of STEC, we aim to highlight the new insights on the contribution of Stx phages and other STEC phages to pathogenicity.
Collapse
Affiliation(s)
- Lorena Rodríguez-Rubio
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Diagonal 643, 08028 Barcelona, Spain; (L.R.-R.); (M.M.)
| | - Nadja Haarmann
- Department of Food Microbiology and Hygiene, Institute of Food Science and Biotechnology, University of Hohenheim, 70599 Stuttgart, Germany; (N.H.); (M.S.)
| | - Maike Schwidder
- Department of Food Microbiology and Hygiene, Institute of Food Science and Biotechnology, University of Hohenheim, 70599 Stuttgart, Germany; (N.H.); (M.S.)
| | - Maite Muniesa
- Department of Genetics, Microbiology and Statistics, University of Barcelona, Diagonal 643, 08028 Barcelona, Spain; (L.R.-R.); (M.M.)
| | - Herbert Schmidt
- Department of Food Microbiology and Hygiene, Institute of Food Science and Biotechnology, University of Hohenheim, 70599 Stuttgart, Germany; (N.H.); (M.S.)
| |
Collapse
|
20
|
A Toxic Environment: a Growing Understanding of How Microbial Communities Affect Escherichia coli O157:H7 Shiga Toxin Expression. Appl Environ Microbiol 2020; 86:AEM.00509-20. [PMID: 32358004 DOI: 10.1128/aem.00509-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) strains, including E. coli O157:H7, cause severe illness in humans due to the production of Shiga toxin (Stx) and other virulence factors. Because Stx is coregulated with lambdoid prophage induction, its expression is especially susceptible to environmental cues. Infections with Stx-producing E. coli can be difficult to model due to the wide range of disease outcomes: some infections are relatively mild, while others have serious complications. Probiotic organisms, members of the gut microbiome, and organic acids can depress Stx production, in many cases by inhibiting the growth of EHEC strains. On the other hand, the factors currently known to amplify Stx act via their effect on the stx-converting phage. Here, we characterize two interactive mechanisms that increase Stx production by O157:H7 strains: first, direct interactions with phage-susceptible E. coli, and second, indirect amplification by secreted factors. Infection of susceptible strains by the stx-converting phage can expand the Stx-producing population in a human or animal host, and phage infection has been shown to modulate virulence in vitro and in vivo Acellular factors, particularly colicins and microcins, can kill O157:H7 cells but may also trigger Stx expression in the process. Colicins, microcins, and other bacteriocins have diverse cellular targets, and many such molecules remain uncharacterized. The identification of additional Stx-amplifying microbial interactions will improve our understanding of E. coli O157:H7 infections and help elucidate the intricate regulation of pathogenicity in EHEC strains.
Collapse
|
21
|
Garriss G, Henriques-Normark B. Lysogeny in Streptococcus pneumoniae. Microorganisms 2020; 8:E1546. [PMID: 33036379 PMCID: PMC7600539 DOI: 10.3390/microorganisms8101546] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 10/05/2020] [Indexed: 12/31/2022] Open
Abstract
Bacterial viruses, or bacteriophages, are major contributors to the evolution, pathogenesis and overall biology of their host bacteria. During their life cycle, temperate bacteriophages form stable associations with their host by integrating into the chromosome, a process called lysogeny. Isolates of the human pathogen Streptococcus pneumoniae are frequently lysogenic, and genomic studies have allowed the classification of these phages into distinct phylogenetic groups. Here, we review the recent advances in the characterization of temperate pneumococcal phages, with a focus on their genetic features and chromosomal integration loci. We also discuss the contribution of phages, and specific phage-encoded features, to colonization and virulence. Finally, we discuss interesting research perspectives in this field.
Collapse
Affiliation(s)
- Geneviève Garriss
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Birgitta Henriques-Normark
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 77 Stockholm, Sweden
- Clinical Microbiology, Karolinska University Hospital, Bioclinicum, 171 76 Stockholm, Sweden
- Lee Kong Chian School of Medicine (LKC) and Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore 639798, Singapore
| |
Collapse
|
22
|
Menge C. The Role of Escherichia coli Shiga Toxins in STEC Colonization of Cattle. Toxins (Basel) 2020; 12:toxins12090607. [PMID: 32967277 PMCID: PMC7551371 DOI: 10.3390/toxins12090607] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/16/2020] [Accepted: 09/18/2020] [Indexed: 11/20/2022] Open
Abstract
Many cattle are persistently colonized with Shiga toxin-producing Escherichia coli (STEC) and represent a major source of human infections with human-pathogenic STEC strains (syn. enterohemorrhagic E. coli (EHEC)). Intervention strategies most effectively protecting humans best aim at the limitation of bovine STEC shedding. Mechanisms enabling STEC to persist in cattle are only partialy understood. Cattle were long believed to resist the detrimental effects of Shiga toxins (Stxs), potent cytotoxins acting as principal virulence factors in the pathogenesis of human EHEC-associated diseases. However, work by different groups, summarized in this review, has provided substantial evidence that different types of target cells for Stxs exist in cattle. Peripheral and intestinal lymphocytes express the Stx receptor globotriaosylceramide (Gb3syn. CD77) in vitro and in vivo in an activation-dependent fashion with Stx-binding isoforms expressed predominantly at early stages of the activation process. Subpopulations of colonic epithelial cells and macrophage-like cells, residing in the bovine mucosa in proximity to STEC colonies, are also targeted by Stxs. STEC-inoculated calves are depressed in mounting appropriate cellular immune responses which can be overcome by vaccination of the animals against Stxs early in life before encountering STEC. Considering Stx target cells and the resulting effects of Stxs in cattle, which significantly differ from effects implicated in human disease, may open promising opportunities to improve existing yet insufficient measures to limit STEC carriage and shedding by the principal reservoir host.
Collapse
Affiliation(s)
- Christian Menge
- Friedrich-Loeffler-Institut/Federal Research Institute for Animal Health, Institute of Molecular Pathogenesis, D-07743 Jena, Germany
| |
Collapse
|
23
|
Yu X, Xu J, Gu Y, Zhang R, Zhu Y, Liu X. Molecular Characterization and Comparative Genomic Analysis of vB_PaeP_YA3, a Novel Temperate Bacteriophage of Pseudomonas aeruginosa. Front Microbiol 2020; 11:947. [PMID: 32655502 PMCID: PMC7326022 DOI: 10.3389/fmicb.2020.00947] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 04/20/2020] [Indexed: 01/21/2023] Open
Abstract
It is well known that bacteriophages play crucial roles in many aspects, such as controlling the number and the diversity of bacteria and participating in horizontal gene transfer, which is a key process in the evolution of bacteria. However, so far, the number of temperate bacteriophages is still limited, and their life processes are severely unknown, except for members of the lambdoid family of coliphages. In this study, a novel temperate phage of Pseudomonas aeruginosa, YA3 (vB_PaeP_YA3), was isolated from waste water. The morphology of YA3 suggested that it is a Podoviridae. The YA3 genome is a circular double-stranded DNA of 45,253 bp, with an average G + C content of 57.2%. A total of 65 open reading frames (ORFs) were predicted according to the sequence of YA3’s genome, of which only 32 (49.2%) ORFs were assigned with putative functions and 13 ORFs were confirmed by the structural proteome. Genome and proteome analyses confirmed the lysogenic nature of this phage, which encodes the typical lysogen-related proteins integrase, CI, Cro, and Q protein. The genome of YA3 is most closely related with that of temperate phage vB_PaeP_Tr60_Ab31, whereas the homology coverage is just 48%. There are many critical differences between their genomes, involving promoters, lysis pathways, and regulation patterns. YA3 is capable of stably lysogenizing its host P. aeruginosa PA14, targeting the integration site within the serine tRNA gene (PA14_RS20820), which is similar with phage vB_PaeP_Tr60_Ab31. The phylogenetic analysis is more complicated than we thought. Based on phage terminase large subunit (TerL) and CI proteins, phage YA3 is related with phage lambda, while their genome coverage is extremely low (<1%). Therefore, phage YA3 is a considerably novel lambda-like temperate phage, and a further study of its genome may deepen our understanding of the interaction between lysogenic phages and their bacterial hosts.
Collapse
Affiliation(s)
- Xinyan Yu
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Microbiology, Nanjing Medical University, Nanjing, China
| | - Jing Xu
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Microbiology, Nanjing Medical University, Nanjing, China
| | - Yu Gu
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Microbiology, Nanjing Medical University, Nanjing, China
| | - Ruiyang Zhang
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Microbiology, Nanjing Medical University, Nanjing, China
| | - Yefei Zhu
- Laboratory Medicine Center, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xiaoqiu Liu
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Microbiology, Nanjing Medical University, Nanjing, China
| |
Collapse
|
24
|
Bufe T, Hennig A, Klumpp J, Weiss A, Nieselt K, Schmidt H. Differential transcriptome analysis of enterohemorrhagic Escherichia coli strains reveals differences in response to plant-derived compounds. BMC Microbiol 2019; 19:212. [PMID: 31488056 PMCID: PMC6729007 DOI: 10.1186/s12866-019-1578-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 08/25/2019] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND Several serious vegetable-associated outbreaks of enterohemorrhagic Escherichia coli (EHEC) infections have occurred during the last decades. In this context, vegetables have been suggested to function as secondary reservoirs for EHEC strains. Increased knowledge about the interaction of EHEC with plants including gene expression patterns in response to plant-derived compounds is required. In the current study, EHEC O157:H7 strain Sakai, EHEC O157:H- strain 3072/96, and the EHEC/enteroaggregative E. coli (EAEC) hybrid O104:H4 strain C227-11φcu were grown in lamb's lettuce medium and in M9 minimal medium to study the differential transcriptional response of these strains to plant-derived compounds with RNA-Seq technology. RESULTS Many genes involved in carbohydrate degradation and peptide utilization were similarly upregulated in all three strains, suggesting that the lamb's lettuce medium provides sufficient nutrients for proliferation. In particular, the genes galET and rbsAC involved in galactose metabolism and D-ribose catabolism, respectively, were uniformly upregulated in the investigated strains. The most prominent differences in shared genome transcript levels were observed for genes involved in the expression of flagella. Transcripts of all three classes of the flagellar hierarchy were highly abundant in strain C227-11φcu. Strain Sakai expressed only genes encoding the basal flagellar structure. In addition, both strains showed increased motility in presence of lamb's lettuce extract. Moreover, strain 3072/96 showed increased transcription activity for genes encoding the type III secretion system (T3SS) including effectors, and was identified as a powerful biofilm-producer in M9 minimal medium. CONCLUSION The current study provides clear evidence that EHEC and EHEC/EAEC strains are able to adjust their gene expression patterns towards metabolization of plant-derived compounds, demonstrating that they may proliferate well in a plant-associated environment. Moreover, we propose that flagella and other surface structures play a fundamental role in the interaction of EHEC and EHEC/EAEC with plants.
Collapse
Affiliation(s)
- Thorsten Bufe
- Department of Food Microbiology and Hygiene, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 28, 70599 Stuttgart, Germany
| | - André Hennig
- Institute for Bioinformatics and Medical Informatics, University of Tübingen, Sand 14, 72076 Tübingen, Germany
| | - Jochen Klumpp
- Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich, Switzerland
| | - Agnes Weiss
- Department of Food Microbiology and Hygiene, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 28, 70599 Stuttgart, Germany
| | - Kay Nieselt
- Institute for Bioinformatics and Medical Informatics, University of Tübingen, Sand 14, 72076 Tübingen, Germany
| | - Herbert Schmidt
- Department of Food Microbiology and Hygiene, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 28, 70599 Stuttgart, Germany
| |
Collapse
|
25
|
Berger P, Kouzel IU, Berger M, Haarmann N, Dobrindt U, Koudelka GB, Mellmann A. Carriage of Shiga toxin phage profoundly affects Escherichia coli gene expression and carbon source utilization. BMC Genomics 2019; 20:504. [PMID: 31208335 PMCID: PMC6580645 DOI: 10.1186/s12864-019-5892-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 06/10/2019] [Indexed: 02/03/2023] Open
Abstract
Background Enterohemorrhagic Escherichia coli (E. coli) are intestinal pathogenic bacteria that cause life-threatening disease in humans. Their cardinal virulence factor is Shiga toxin (Stx), which is encoded on lambdoid phages integrated in the chromosome. Stx phages can infect and lysogenize susceptible bacteria, thus either increasing the virulence of already pathogenic bacterial hosts or transforming commensal strains into potential pathogens. There is increasing evidence that Stx phage-encoded factors adaptively regulate bacterial host gene expression. Here, we investigated the effects of Stx phage carriage in E. coli K-12 strain MG1655. We compared the transcriptome and phenotype of naive MG1655 and two lysogens carrying closely related Stx2a phages: ϕO104 from the exceptionally pathogenic 2011 E. coli O104:H4 outbreak strain and ϕPA8 from an E. coli O157:H7 isolate. Results Analysis of quantitative RNA sequencing results showed that, in comparison to naive MG1655, genes involved in mixed acid fermentation were upregulated, while genes encoding NADH dehydrogenase I, TCA cycle enzymes and proteins involved in the transport and assimilation of carbon sources were downregulated in MG1655::ϕO104 and MG1655::ϕPA8. The majority of the changes in gene expression were found associated with the corresponding phenotypes. Notably, the Stx2a phage lysogens displayed moderate to severe growth defects in minimal medium supplemented with single carbon sources, e.g. galactose, ribose, L-lactate. In addition, in phenotype microarray assays, the Stx2a phage lysogens were characterized by a significant decrease in the cell respiration with gluconeogenic substrates such as amino acids, nucleosides, carboxylic and dicarboxylic acids. In contrast, MG1655::ϕO104 and MG1655::ϕPA8 displayed enhanced respiration with several sugar components of the intestinal mucus, e.g. arabinose, fucose, N-acetyl-D-glucosamine. We also found that prophage-encoded factors distinct from CI and Cro were responsible for the carbon utilization phenotypes of the Stx2a phage lysogens. Conclusions Our study reveals a profound impact of the Stx phage carriage on E. coli carbon source utilization. The Stx2a prophage appears to reprogram the carbon metabolism of its bacterial host by turning down aerobic metabolism in favour of mixed acid fermentation. Electronic supplementary material The online version of this article (10.1186/s12864-019-5892-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Petya Berger
- Institute of Hygiene, University of Münster, Münster, Germany.
| | - Ivan U Kouzel
- Institute of Hygiene, University of Münster, Münster, Germany.,Institute of Bioinformatics, University of Münster, Münster, Germany
| | - Michael Berger
- Institute of Hygiene, University of Münster, Münster, Germany
| | - Nadja Haarmann
- Institute of Hygiene, University of Münster, Münster, Germany
| | - Ulrich Dobrindt
- Institute of Hygiene, University of Münster, Münster, Germany
| | - Gerald B Koudelka
- Department of Biological Sciences, University at Buffalo, Buffalo, USA
| | | |
Collapse
|
26
|
Magaziner SJ, Zeng Z, Chen B, Salmond GPC. The Prophages of Citrobacter rodentium Represent a Conserved Family of Horizontally Acquired Mobile Genetic Elements Associated with Enteric Evolution towards Pathogenicity. J Bacteriol 2019; 201:e00638-18. [PMID: 30782635 PMCID: PMC6456863 DOI: 10.1128/jb.00638-18] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 01/23/2019] [Indexed: 01/08/2023] Open
Abstract
Prophage-mediated horizontal gene transfer (HGT) plays a key role in the evolution of bacteria, enabling access to new environmental niches, including pathogenicity. Citrobacter rodentium is a host-adapted intestinal mouse pathogen and important model organism for attaching and effacing (A/E) pathogens, including the clinically significant enterohaemorrhagic and enteropathogenic Escherichia coli (EHEC and EPEC, respectively). Even though C. rodentium contains 10 prophage genomic regions, including an active temperate phage, ΦNP, little was known regarding the nature of C. rodentium prophages in the bacterium's evolution toward pathogenicity. In this study, our characterization of ΦNP led to the discovery of a second, fully functional temperate phage, named ΦSM. We identify the bacterial host receptor for both phages as lipopolysaccharide (LPS). ΦNP and ΦSM are likely important mediators of HGT in C. rodentium Bioinformatic analysis of the 10 prophage regions reveals cargo genes encoding known virulence factors, including several type III secretion system (T3SS) effectors. C. rodentium prophages are conserved across a wide range of pathogenic enteric bacteria, including EPEC and EHEC as well as pathogenic strains of Salmonella enterica, Shigella boydii, and Klebsiella pneumoniae Phylogenetic analysis of core enteric backbone genes compared against prophage evolutionary models suggests that these prophages represent an important, conserved family of horizontally acquired enteric-bacterium-associated pathogenicity determinants. In addition to highlighting the transformative role of bacteriophage-mediated HGT in C. rodentium's evolution toward pathogenicity, these data suggest that the examination of conserved families of prophages in other pathogenic bacteria and disease outbreaks might provide deeper evolutionary and pathological insights otherwise obscured by more classical analysis.IMPORTANCE Bacteriophages are obligate intracellular parasites of bacteria. Some bacteriophages can confer novel bacterial phenotypes, including pathogenicity, through horizontal gene transfer (HGT). The pathogenic bacterium Citrobacter rodentium infects mice using mechanisms similar to those employed by human gastrointestinal pathogens, making it an important model organism. Here, we examined the 10 prophages of C. rodentium, investigating their roles in its evolution toward virulence. We characterized ΦNP and ΦSM, two endogenous active temperate bacteriophages likely important for HGT. We showed that the 10 prophages encode predicted virulence factors and are conserved within other intestinal pathogens. Phylogenetic analysis suggested that they represent a conserved family of horizontally acquired enteric-bacterium-associated pathogenic determinants. Consequently, similar analysis of prophage elements in other pathogens might further understanding of their evolution and pathology.
Collapse
Affiliation(s)
- Samuel J Magaziner
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Ziyue Zeng
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Bihe Chen
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - George P C Salmond
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| |
Collapse
|
27
|
Song S, Guo Y, Kim JS, Wang X, Wood TK. Phages Mediate Bacterial Self-Recognition. Cell Rep 2019; 27:737-749.e4. [DOI: 10.1016/j.celrep.2019.03.070] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 02/07/2019] [Accepted: 03/18/2019] [Indexed: 12/26/2022] Open
|
28
|
Mukhopadhya I, Segal JP, Carding SR, Hart AL, Hold GL. The gut virome: the 'missing link' between gut bacteria and host immunity? Therap Adv Gastroenterol 2019; 12:1756284819836620. [PMID: 30936943 PMCID: PMC6435874 DOI: 10.1177/1756284819836620] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Accepted: 02/14/2019] [Indexed: 02/04/2023] Open
Abstract
The human gut virome includes a diverse collection of viruses that infect our own cells as well as other commensal organisms, directly impacting on our well-being. Despite its predominance, the virome remains one of the least understood components of the gut microbiota, with appropriate analysis toolkits still in development. Based on its interconnectivity with all living cells, it is clear that the virome cannot be studied in isolation. Here we review the current understanding of the human gut virome, specifically in relation to other constituents of the microbiome, its evolution and life-long association with its host, and our current understanding in the context of inflammatory bowel disease and associated therapies. We propose that the gut virome and the gut bacterial microbiome share similar trajectories and interact in both health and disease and that future microbiota studies should in parallel characterize the gut virome to uncover its role in health and disease.
Collapse
Affiliation(s)
- Indrani Mukhopadhya
- Gastrointestinal Research Group, Division of Applied Medicine, University of Aberdeen, Foresterhill, Aberdeen, UK Gut Health Group, The Rowett Institute, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Jonathan P. Segal
- St. Mark’s Hospital, Watford Road, Harrow, UK Imperial College London, South Kensington Campus, Department of Surgery and Cancer, London, UK
| | - Simon R. Carding
- Gut Microbes and Health Research Programme, The Quadram Institute, Norwich Research Park, Norwich, Norfolk, UK Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, Norfolk, UK
| | - Ailsa L. Hart
- St. Mark’s Hospital, Watford Road, Harrow, UK Imperial College London, South Kensington Campus, Department of Surgery and Cancer, London, UK
| | | |
Collapse
|
29
|
Rowan-Nash AD, Korry BJ, Mylonakis E, Belenky P. Cross-Domain and Viral Interactions in the Microbiome. Microbiol Mol Biol Rev 2019; 83:e00044-18. [PMID: 30626617 PMCID: PMC6383444 DOI: 10.1128/mmbr.00044-18] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The importance of the microbiome to human health is increasingly recognized and has become a major focus of recent research. However, much of the work has focused on a few aspects, particularly the bacterial component of the microbiome, most frequently in the gastrointestinal tract. Yet humans and other animals can be colonized by a wide array of organisms spanning all domains of life, including bacteria and archaea, unicellular eukaryotes such as fungi, multicellular eukaryotes such as helminths, and viruses. As they share the same host niches, they can compete with, synergize with, and antagonize each other, with potential impacts on their host. Here, we discuss these major groups making up the human microbiome, with a focus on how they interact with each other and their multicellular host.
Collapse
Affiliation(s)
- Aislinn D Rowan-Nash
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
| | - Benjamin J Korry
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
| | - Eleftherios Mylonakis
- Infectious Diseases Division, Warren Alpert Medical School of Brown University, Rhode Island Hospital, Providence, Rhode Island, USA
| | - Peter Belenky
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
| |
Collapse
|
30
|
Balasubramanian S, Osburne MS, BrinJones H, Tai AK, Leong JM. Prophage induction, but not production of phage particles, is required for lethal disease in a microbiome-replete murine model of enterohemorrhagic E. coli infection. PLoS Pathog 2019; 15:e1007494. [PMID: 30629725 PMCID: PMC6328086 DOI: 10.1371/journal.ppat.1007494] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 12/01/2018] [Indexed: 12/12/2022] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) colonize intestinal epithelium by generating characteristic attaching and effacing (AE) lesions. They are lysogenized by prophage that encode Shiga toxin 2 (Stx2), which is responsible for severe clinical manifestations. As a lysogen, prophage genes leading to lytic growth and stx2 expression are repressed, whereas induction of the bacterial SOS response in response to DNA damage leads to lytic phage growth and Stx2 production both in vitro and in germ-free or streptomycin-treated mice. Some commensal bacteria diminish prophage induction and concomitant Stx2 production in vitro, whereas it has been proposed that phage-susceptible commensals may amplify Stx2 production by facilitating successive cycles of infection in vivo. We tested the role of phage induction in both Stx production and lethal disease in microbiome-replete mice, using our mouse model encompassing the murine pathogen Citrobacter rodentium lysogenized with the Stx2-encoding phage Φstx2dact. This strain generates EHEC-like AE lesions on the murine intestine and causes lethal Stx-mediated disease. We found that lethal mouse infection did not require that Φstx2dact infect or lysogenize commensal bacteria. In addition, we detected circularized phage genomes, potentially in the early stage of replication, in feces of infected mice, confirming that prophage induction occurs during infection of microbiota-replete mice. Further, C. rodentium (Φstx2dact) mutants that do not respond to DNA damage or express stx produced neither high levels of Stx2 in vitro or lethal infection in vivo, confirming that SOS induction and concomitant expression of phage-encoded stx genes are required for disease. In contrast, C. rodentium (Φstx2dact) mutants incapable of prophage genome excision or of packaging phage genomes retained the ability to produce Stx in vitro, as well as to cause lethal disease in mice. Thus, in a microbiome-replete EHEC infection model, lytic induction of Stx-encoding prophage is essential for lethal disease, but actual phage production is not.
Collapse
Affiliation(s)
- Sowmya Balasubramanian
- Department of Molecular Biology and Microbiology at Tufts University School of Medicine, Boston, MA, United States of America
| | - Marcia S. Osburne
- Department of Molecular Biology and Microbiology at Tufts University School of Medicine, Boston, MA, United States of America
| | - Haley BrinJones
- Department of Molecular Biology and Microbiology at Tufts University School of Medicine, Boston, MA, United States of America
| | - Albert K. Tai
- Department of Immunology at Tufts University School of Medicine, Boston, MA, United States of America
| | - John M. Leong
- Department of Molecular Biology and Microbiology at Tufts University School of Medicine, Boston, MA, United States of America
| |
Collapse
|
31
|
Control freaks-signals and cues governing the regulation of virulence in attaching and effacing pathogens. Biochem Soc Trans 2018; 47:229-238. [PMID: 30559275 PMCID: PMC6393859 DOI: 10.1042/bst20180546] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 11/08/2018] [Accepted: 11/13/2018] [Indexed: 02/07/2023]
Abstract
Enterohaemorrhagic Escherichia coli (EHEC) mediates disease using a type 3 secretion system (T3SS), which is encoded on the locus of enterocyte effacement (LEE) and is tightly controlled by master regulators. This system is further modulated by a number of signals that help to fine-tune virulence, including metabolic, environmental and chemical signals. Since the LEE and its master regulator, Ler, were established, there have been numerous scientific advancements in understanding the regulation and expression of virulence factors in EHEC. This review will discuss the recent advancements in this field since our previous review, with a focus on the transcriptional regulation of the LEE.
Collapse
|
32
|
Dextran Sulfate Sodium Colitis Facilitates Colonization with Shiga Toxin-Producing Escherichia coli: a Novel Murine Model for the Study of Shiga Toxicosis. Infect Immun 2018; 86:IAI.00530-18. [PMID: 30150257 DOI: 10.1128/iai.00530-18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 08/23/2018] [Indexed: 12/23/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) bacteria are globally important gastrointestinal pathogens causing hemorrhagic gastroenteritis with variable progression to potentially fatal Shiga toxicosis. Little is known about the potential effects of E. coli-derived Shiga-like toxins (STXs) on host gastrointestinal immune responses during infection, in part due to the lack of a reproducible immunocompetent-animal model of STEC infection without depleting the commensal microbiota. Here, we describe a novel and reproducible murine model utilizing dextran sulfate sodium (DSS) colitis to induce susceptibility to colonization with clinical-isolate STEC strains. After exposure to DSS and subsequent oral STEC challenge, all the mice were colonized, and 66% of STEC-infected mice required early euthanasia. Morbidity during STEC infection, but not infection with an isogenic STEC mutant with toxin deleted, was associated with increased renal transcripts of the injury markers KIM1 and NGAL, histological evidence of renal tubular injury, and increased renal interleukin 6 gene (IL-6) and CXCL1 inflammatory transcripts. Interestingly, the intestinal burden of STEC during infection was increased compared to its isogenic Shiga toxin deletion strain. Increased bacterial burdens during Shiga toxin production coincided with decreased induction of colonic IL-23 axis transcripts known to be critical for clearance of similar gastrointestinal pathogens in mice, suggesting a previously undescribed role for STEC Shiga toxins in suppressing host immune responses during STEC infection and survival. The DSS+STEC model establishes infection with clinical-isolate strains of STEC in immunocompetent mice without depleting the gastrointestinal microbiota, enabling characterization of the effects of STXs on the IL-23 axis and other gastrointestinal pathogen-host interactions.
Collapse
|
33
|
Haarmann N, Berger M, Kouzel IU, Mellmann A, Berger P. Comparative virulence characterization of the Shiga toxin phage-cured Escherichia coli O104:H4 and enteroaggregative Escherichia coli. Int J Med Microbiol 2018; 308:912-920. [DOI: 10.1016/j.ijmm.2018.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 06/04/2018] [Accepted: 06/16/2018] [Indexed: 12/26/2022] Open
|
34
|
|