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Zhang D, Wang Z, Yamamoto N, Wang M, Yi X, Li P, Lin R, Nasimi Z, Okada K, Mochida K, Noutoshi Y, Zheng A. Secreted Glycosyltransferase RsIA_GT of Rhizoctonia solani AG-1 IA Inhibits Defense Responses in Nicotiana benthamiana. Pathogens 2022; 11:pathogens11091026. [PMID: 36145458 PMCID: PMC9501517 DOI: 10.3390/pathogens11091026] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 08/31/2022] [Accepted: 09/03/2022] [Indexed: 11/16/2022] Open
Abstract
Anastomosis group AG-1 IA of Rhizoctonia solani Khün has a wide host range and threatens crop production. Various glycosyltransferases secreted by phytopathogenic fungi play an essential role in pathogenicity. Previously, we identified a glycosyltransferase RsIA_GT (AG11A_09161) as a secreted protein-encoding gene of R. solani AG-1 IA, whose expression levels increased during infection in rice. In this study, we further characterized the virulence function of RsIA_GT. It is conserved not only in Basidiomycota, including multiple anastomosis groups of R. solani, but also in other primary fungal taxonomic categories. RsIA_GT possesses a signal peptide (SP) for protein secretion, and its functionality was proven using yeast and Nicotiana benthamiana. The SP-truncated form of RsIA_GT (RsIA_GT(ΔS)) expressed in Escherichia coli-induced lesion-like phenotype in rice leaves when applied to punched leaves. However, Agrobacterium-mediated transient expressions of both the full-length RsIA_GT and RsIA_GT(ΔS) did not induce cell death in N. benthamiana leaves. Instead, only RsIA_GT(ΔS) suppressed the cell death induced by two reference cell death factors BAX and INF1 in N.benthamiana. RsIA_GT(ΔS)R154A D168A D170A, a mutant RsIA_GT(ΔS) for the glycosyltransferase catalytic domain, still suppressed the BAX- or INF1-induced cell death, suggesting that the cell death suppression activity of RsIA_GT(ΔS) would be independent from its enzymatic activity. RsIA_GT(ΔS) also suppressed the H2O2 production and callose deposition and showed an effect on the induction of defense genes associated with the expression of BAX and INF1. The transient expression of RsIA_GT(ΔS) in N. benthamiana enhanced the lesion area caused by R. solani AG-1 IA. The secreted glycosyltransferase, RsIA_GT, of R. solani AG-1 IA is likely to have a dual role in virulence inside and outside of host cells.
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Affiliation(s)
- Danhua Zhang
- College of Agronomy, Sichuan Agricultural University, Chengdu 611130, China
| | - Zhaoyilin Wang
- Rice Research Institute, Sichuan Agricultural University, Chengdu 611130, China
| | - Naoki Yamamoto
- College of Agronomy, Sichuan Agricultural University, Chengdu 611130, China
| | - Mingyue Wang
- College of Agronomy, Sichuan Agricultural University, Chengdu 611130, China
| | - Xiaoqun Yi
- College of Agronomy, Sichuan Agricultural University, Chengdu 611130, China
| | - Ping Li
- Rice Research Institute, Sichuan Agricultural University, Chengdu 611130, China
| | - Runmao Lin
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Zohreh Nasimi
- College of Agronomy, Sichuan Agricultural University, Chengdu 611130, China
| | - Kazunori Okada
- Agro-Biotechnology Research Center, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Keiichi Mochida
- Bioproductivity Informatics Research Team, RIKEN Center for Sustainable Resource Science, Yokohama 2300045, Japan
- Microalgae Production Control Technology Laboratory, RIKEN Baton Zone Program, RIKEN Cluster for Science, Technology and Innovation Hub, Yokohama 2300045, Japan
- Kihara Institute for Biological Research, Yokohama City University, Yokohama 2440813, Japan
- School of Information and Data Sciences, Nagasaki University, Nagasaki 852-8521, Japan
| | - Yoshiteru Noutoshi
- Graduate School of Environmental and Life Science, Okayama University, Okayama 700-8530, Japan
| | - Aiping Zheng
- College of Agronomy, Sichuan Agricultural University, Chengdu 611130, China
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu 611130, China
- Correspondence:
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Reprogramming of Cell Death Pathways by Bacterial Effectors as a Widespread Virulence Strategy. Infect Immun 2022; 90:e0061421. [PMID: 35467397 DOI: 10.1128/iai.00614-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The modulation of programmed cell death (PCD) processes during bacterial infections is an evolving arms race between pathogens and their hosts. The initiation of apoptosis, necroptosis, and pyroptosis pathways are essential to immunity against many intracellular and extracellular bacteria. These cellular self-destructive mechanisms are used by the infected host to restrict and eliminate bacterial pathogens. Without a tight regulatory control, host cell death can become a double-edged sword. Inflammatory PCDs contribute to an effective immune response against pathogens, but unregulated inflammation aggravates the damage caused by bacterial infections. Thus, fine-tuning of these pathways is required to resolve infection while preserving the host immune homeostasis. In turn, bacterial pathogens have evolved secreted virulence factors or effector proteins that manipulate PCD pathways to promote infection. In this review, we discuss the importance of controlled cell death in immunity to bacterial infection. We also detail the mechanisms employed by type 3 secreted bacterial effectors to bypass these pathways and their importance in bacterial pathogenesis.
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Giogha C, Scott NE, Wong Fok Lung T, Pollock GL, Harper M, Goddard-Borger ED, Pearson JS, Hartland EL. NleB2 from enteropathogenic Escherichia coli is a novel arginine-glucose transferase effector. PLoS Pathog 2021; 17:e1009658. [PMID: 34133469 PMCID: PMC8238200 DOI: 10.1371/journal.ppat.1009658] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 06/28/2021] [Accepted: 05/20/2021] [Indexed: 12/12/2022] Open
Abstract
During infection, enteropathogenic Escherichia coli (EPEC) and enterohaemorrhagic E. coli (EHEC) directly manipulate various aspects of host cell function through the translocation of type III secretion system (T3SS) effector proteins directly into the host cell. Many T3SS effector proteins are enzymes that mediate post-translational modifications of host proteins, such as the glycosyltransferase NleB1, which transfers a single N-acetylglucosamine (GlcNAc) to arginine residues, creating an Arg-GlcNAc linkage. NleB1 glycosylates death-domain containing proteins including FADD, TRADD and RIPK1 to block host cell death. The NleB1 paralogue, NleB2, is found in many EPEC and EHEC strains but to date its enzymatic activity has not been described. Using in vitro glycosylation assays combined with mass spectrometry, we found that NleB2 can utilize multiple sugar donors including UDP-glucose, UDP-GlcNAc and UDP-galactose during glycosylation of the death domain protein, RIPK1. Sugar donor competition assays demonstrated that UDP-glucose was the preferred substrate of NleB2 and peptide sequencing identified the glycosylation site within RIPK1 as Arg603, indicating that NleB2 catalyses arginine glucosylation. We also confirmed that NleB2 catalysed arginine-hexose modification of Flag-RIPK1 during infection of HEK293T cells with EPEC E2348/69. Using site-directed mutagenesis and in vitro glycosylation assays, we identified that residue Ser252 in NleB2 contributes to the specificity of this distinct catalytic activity. Substitution of Ser252 in NleB2 to Gly, or substitution of the corresponding Gly255 in NleB1 to Ser switches sugar donor preference between UDP-GlcNAc and UDP-glucose. However, this switch did not affect the ability of the NleB variants to inhibit inflammatory or cell death signalling during HeLa cell transfection or EPEC infection. NleB2 is thus the first identified bacterial Arg-glucose transferase that, similar to the NleB1 Arg-GlcNAc transferase, inhibits host protein function by arginine glycosylation. Bacterial gut pathogens including enteropathogenic E. coli (EPEC) and enterohaemorrhagic E. coli (EHEC), manipulate host cell function by using a type III secretion system to inject ‘effector’ proteins directly into the host cell cytoplasm. We and others have shown that many of these effectors are novel enzymes, including NleB1, which transfers a single N-acetylglucosamine (GlcNAc) sugar to arginine residues, mediating Arg-GlcNAc glycosylation. Here, we found that a close homologue of NleB1 that is also present in EPEC and EHEC termed NleB2, uses a different sugar during glycosylation. We demonstrated that in contrast to NleB1, the preferred nucleotide-sugar substrate of NleB2 is UDP-glucose and we identified the amino acid residue within NleB2 that dictates this unique catalytic activity. Substitution of this residue in NleB2 and NleB1 switches the sugar donor usage of these enzymes but does not affect their ability to inhibit host cell signalling. Thus, NleB2 is the first identified bacterial arginine-glucose transferase, an activity which has previously only been described in plants and algae.
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Affiliation(s)
- Cristina Giogha
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
| | - Nichollas E. Scott
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Tania Wong Fok Lung
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Georgina L. Pollock
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
| | - Marina Harper
- Department of Microbiology, Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Ethan D. Goddard-Borger
- ACRF Chemical Biology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, Australia
| | - Jaclyn S. Pearson
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Elizabeth L. Hartland
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
- * E-mail:
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Koh E, Cho HS. NleB/SseKs ortholog effectors as a general bacterial monoglycosyltransferase for eukaryotic proteins. Curr Opin Struct Biol 2021; 68:215-223. [PMID: 33761453 DOI: 10.1016/j.sbi.2021.02.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 12/20/2022]
Abstract
Protein glycosylation is the most common post-translational modification as more than 50% of all human proteins are glycosylated. Pathogenic bacteria glycosylation allows adhesion to host cells and manipulates eukaryotic functions. A variety of acceptor proteins in bacterial glycosylation was recently discovered. Especially NleB/SseKs type III effectors unexpectedly glycosylate a poor nucleophile arginine. Other pathogenic toxins modify the unusual tyrosine, as well as canonical serine/threonine residues. And a huge diversity is found in target proteins; Rho/Ras families, death domains and moreover themselves for autoglycosylation. However, in spite of this acceptor diversity, all their sugar donors are only UDP-Glc/-GlcNAc and structural alignments as liganded show their catalytic cores are geometrically conserved, where DRY and DXD motives and W residues equally position to hold the sugar donors and to π-π bind with a uridine ring, respectively. Therefore, bacterial glycosyltransferases have a key for carbohydrate research problems concerning the sugar donors and target proteins recognition.
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Affiliation(s)
- Eunhee Koh
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Hyun-Soo Cho
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea.
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Riebisch AK, Mühlen S. Attaching and effacing pathogens: the effector ABC of immune subversion. Future Microbiol 2020; 15:945-958. [PMID: 32716209 DOI: 10.2217/fmb-2019-0274] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The innate immune response resembles an essential barrier to bacterial infection. Many bacterial pathogens have, therefore, evolved mechanisms to evade from or subvert the host immune response in order to colonize, survive and multiply. The attaching and effacing pathogens enteropathogenic Escherichia coli, enterohaemorrhagic E. coli, Escherichia albertii and Citrobacter rodentium are Gram-negative extracellular gastrointestinal pathogens. They use a type III secretion system to inject effector proteins into the host cell to manipulate a variety of cellular processes. Over the last decade, considerable progress was made in identifying and characterizing the effector proteins of attaching and effacing pathogens that are involved in the inhibition of innate immune signaling pathways, in determining their host cell targets and elucidating the mechanisms they employ. Their functions will be reviewed here.
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Affiliation(s)
- Anna Katharina Riebisch
- Systems-Oriented Immunology & Inflammation Research, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany.,Institute for Molecular & Clinical Immunology, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany.,Department of Molecular Immunology, Ruhr-University Bochum, 44801 Bochum, Germany
| | - Sabrina Mühlen
- Institute for Infectiology, University of Münster, 48149 Münster, Germany.,German Center for Infection Research (DZIF), Associated Site University of Münster, 48149 Münster, Germany
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Pan X, Luo J, Li S. Bacteria-Catalyzed Arginine Glycosylation in Pathogens and Host. Front Cell Infect Microbiol 2020; 10:185. [PMID: 32411621 PMCID: PMC7199390 DOI: 10.3389/fcimb.2020.00185] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 04/07/2020] [Indexed: 01/25/2023] Open
Abstract
In recent years, protein glycosylation in pathogenic bacteria has attracted more and more attention, and accumulating evidence indicated that this type of posttranslational modification is involved in many physiological processes. The NleB from several enteropathogenic bacteria species as well as SseK from Salmonella enterica are type III secretion system effectors, which have an atypical N-acetylglucosamine (N-GlcNAc) transferase activity that specifically modified a conserved arginine in TRADD, FADD, and RIPK1. NleB/SseKs GlcNAcylation of death domain proteins abrogates homotypic and heterotypic death receptors/adaptors interactions, thereby blocking an important antimicrobial host response. Interestingly, NleB/SseKs could also GlcNAcylate themselves, and self-GlcNAcylation of NleB, SseK1, and SseK3 are crucial for their biological activity during infection. In addition, EarP (EF-P specific arginine rhamnosyl transferase for Posttranslational activation) catalyzes arginine rhamnosylation of translation elongation factor P (EF-P). Importantly, this kind of N-linked protein glycosylation is not only important for EF-P dependent rescue of polyproline stalled ribosomes but also for pathogenicity in Pseudomonas aeruginosa and other clinically relevant bacteria. Glycosylation of arginine is unique because the guanidine group of arginine has a high acid dissociation constant value and representing an extremely poor nucleophile. Recently, the crystal structures of NleB, SseKs, EarP, arginine GlcNAcylated death domain-containing proteins, NleB/FADD-DD, and EarP/EF-P/dTDP-β-L-rhamnose were solved by our group and other groups, revealing the unique catalytic mechanisms. In this review, we provide detailed information about the currently known arginine glycosyltransferases and their potential catalytic mechanisms.
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Affiliation(s)
- Xing Pan
- Institute of Infection and Immunity, Taihe Hospital, Hubei University of Medicine, Shiyan, China.,College of Biomedicine and Health, Huazhong Agricultural University, Wuhan, China.,College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jie Luo
- Institute of Infection and Immunity, Taihe Hospital, Hubei University of Medicine, Shiyan, China
| | - Shan Li
- Institute of Infection and Immunity, Taihe Hospital, Hubei University of Medicine, Shiyan, China.,College of Biomedicine and Health, Huazhong Agricultural University, Wuhan, China.,College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
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7
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Type III Secretion Effectors with Arginine N-Glycosyltransferase Activity. Microorganisms 2020; 8:microorganisms8030357. [PMID: 32131463 PMCID: PMC7142665 DOI: 10.3390/microorganisms8030357] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 02/27/2020] [Accepted: 02/29/2020] [Indexed: 01/31/2023] Open
Abstract
Type III secretion systems are used by many Gram-negative bacterial pathogens to inject proteins, known as effectors, into the cytosol of host cells. These virulence factors interfere with a diverse array of host signal transduction pathways and cellular processes. Many effectors have catalytic activities to promote post-translational modifications of host proteins. This review focuses on a family of effectors with glycosyltransferase activity that catalyze addition of N-acetyl-d-glucosamine to specific arginine residues in target proteins, leading to reduced NF-κB pathway activation and impaired host cell death. This family includes NleB from Citrobacter rodentium, NleB1 and NleB2 from enteropathogenic and enterohemorrhagic Escherichia coli, and SseK1, SseK2, and SseK3 from Salmonella enterica. First, we place these effectors in the general framework of the glycosyltransferase superfamily and in the particular context of the role of glycosylation in bacterial pathogenesis. Then, we provide detailed information about currently known members of this family, their role in virulence, and their targets.
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Lassak J, Koller F, Krafczyk R, Volkwein W. Exceptionally versatile – arginine in bacterial post-translational protein modifications. Biol Chem 2019; 400:1397-1427. [DOI: 10.1515/hsz-2019-0182] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 06/01/2019] [Indexed: 12/24/2022]
Abstract
Abstract
Post-translational modifications (PTM) are the evolutionary solution to challenge and extend the boundaries of genetically predetermined proteomic diversity. As PTMs are highly dynamic, they also hold an enormous regulatory potential. It is therefore not surprising that out of the 20 proteinogenic amino acids, 15 can be post-translationally modified. Even the relatively inert guanidino group of arginine is subject to a multitude of mostly enzyme mediated chemical changes. The resulting alterations can have a major influence on protein function. In this review, we will discuss how bacteria control their cellular processes and develop pathogenicity based on post-translational protein-arginine modifications.
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Affiliation(s)
- Jürgen Lassak
- Center for Integrated Protein Science Munich (CiPSM), Department of Biology I, Microbiology , Ludwig-Maximilians-Universität München , Grosshaderner Strasse 2-4 , D-82152 Planegg , Germany
| | - Franziska Koller
- Center for Integrated Protein Science Munich (CiPSM), Department of Biology I, Microbiology , Ludwig-Maximilians-Universität München , Grosshaderner Strasse 2-4 , D-82152 Planegg , Germany
| | - Ralph Krafczyk
- Center for Integrated Protein Science Munich (CiPSM), Department of Biology I, Microbiology , Ludwig-Maximilians-Universität München , Grosshaderner Strasse 2-4 , D-82152 Planegg , Germany
| | - Wolfram Volkwein
- Center for Integrated Protein Science Munich (CiPSM), Department of Biology I, Microbiology , Ludwig-Maximilians-Universität München , Grosshaderner Strasse 2-4 , D-82152 Planegg , Germany
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9
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Newson JPM, Scott NE, Yeuk Wah Chung I, Wong Fok Lung T, Giogha C, Gan J, Wang N, Strugnell RA, Brown NF, Cygler M, Pearson JS, Hartland EL. Salmonella Effectors SseK1 and SseK3 Target Death Domain Proteins in the TNF and TRAIL Signaling Pathways. Mol Cell Proteomics 2019; 18:1138-1156. [PMID: 30902834 PMCID: PMC6553940 DOI: 10.1074/mcp.ra118.001093] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 02/13/2019] [Indexed: 01/09/2023] Open
Abstract
Strains of Salmonella utilize two distinct type three secretion systems to deliver effector proteins directly into host cells. The Salmonella effectors SseK1 and SseK3 are arginine glycosyltransferases that modify mammalian death domain containing proteins with N-acetyl glucosamine (GlcNAc) when overexpressed ectopically or as recombinant protein fusions. Here, we combined Arg-GlcNAc glycopeptide immunoprecipitation and mass spectrometry to identify host proteins GlcNAcylated by endogenous levels of SseK1 and SseK3 during Salmonella infection. We observed that SseK1 modified the mammalian signaling protein TRADD, but not FADD as previously reported. Overexpression of SseK1 greatly broadened substrate specificity, whereas ectopic co-expression of SseK1 and TRADD increased the range of modified arginine residues within the death domain of TRADD. In contrast, endogenous levels of SseK3 resulted in modification of the death domains of receptors of the mammalian TNF superfamily, TNFR1 and TRAILR, at residues Arg376 and Arg293 respectively. Structural studies on SseK3 showed that the enzyme displays a classic GT-A glycosyltransferase fold and binds UDP-GlcNAc in a narrow and deep cleft with the GlcNAc facing the surface. Together our data suggest that salmonellae carrying sseK1 and sseK3 employ the glycosyltransferase effectors to antagonise different components of death receptor signaling.
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Affiliation(s)
- Joshua P M Newson
- From the ‡Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Nichollas E Scott
- From the ‡Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Ivy Yeuk Wah Chung
- §Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Tania Wong Fok Lung
- From the ‡Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Cristina Giogha
- ¶Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Jiyao Gan
- From the ‡Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
- ¶Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Nancy Wang
- From the ‡Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Richard A Strugnell
- From the ‡Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Nathaniel F Brown
- **Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
| | - Miroslaw Cygler
- §Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Jaclyn S Pearson
- ¶Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Elizabeth L Hartland
- From the ‡Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia;
- ¶Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- ‖Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
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Ding J, Pan X, Du L, Yao Q, Xue J, Yao H, Wang DC, Li S, Shao F. Structural and Functional Insights into Host Death Domains Inactivation by the Bacterial Arginine GlcNAcyltransferase Effector. Mol Cell 2019; 74:922-935.e6. [PMID: 30979585 DOI: 10.1016/j.molcel.2019.03.028] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 12/27/2018] [Accepted: 03/22/2019] [Indexed: 01/10/2023]
Abstract
Enteropathogenic E. coli NleB and related type III effectors catalyze arginine GlcNAcylation of death domain (DD) proteins to block host defense, but the underlying mechanism is unknown. Here we solve crystal structures of NleB alone and in complex with FADD-DD, UDP, and Mn2+ as well as NleB-GlcNAcylated DDs of TRADD and RIPK1. NleB adopts a GT-A fold with a unique helix-pair insertion to hold FADD-DD; the interface contacts explain the selectivity of NleB for certain DDs. The acceptor arginine is fixed into a cleft, in which Glu253 serves as a base to activate the guanidinium. Analyses of the enzyme-substrate complex and the product structures reveal an inverting sugar-transfer reaction and a detailed catalytic mechanism. These structural insights are validated by mutagenesis analyses of NleB-mediated GlcNAcylation in vitro and its function in mouse infection. Our study builds a structural framework for understanding of NleB-catalyzed arginine GlcNAcylation of host death domain.
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Affiliation(s)
- Jingjin Ding
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; National Institute of Biological Sciences, Beijing 102206, China.
| | - Xing Pan
- Bio-Medical Center, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China; Institute of Infection and Immunity, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, China
| | - Lijie Du
- Institute of Infection and Immunity, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, China
| | - Qing Yao
- National Institute of Biological Sciences, Beijing 102206, China
| | - Juan Xue
- Institute of Infection and Immunity, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, China
| | - Hongwei Yao
- College of Chemistry and Chemical Engineering, High-Field Nuclear Magnetic Resonance Center, Xiamen University, Xiamen, Fujian 361005, China
| | - Da-Cheng Wang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Shan Li
- Bio-Medical Center, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China; Institute of Infection and Immunity, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, China.
| | - Feng Shao
- National Institute of Biological Sciences, Beijing 102206, China; Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing 102206, China.
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11
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Esposito D, Günster RA, Martino L, El Omari K, Wagner A, Thurston TLM, Rittinger K. Structural basis for the glycosyltransferase activity of the Salmonella effector SseK3. J Biol Chem 2018; 293:5064-5078. [PMID: 29449376 PMCID: PMC5892559 DOI: 10.1074/jbc.ra118.001796] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 01/31/2018] [Indexed: 01/03/2023] Open
Abstract
The Salmonella-secreted effector SseK3 translocates into host cells, targeting innate immune responses, including NF-κB activation. SseK3 is a glycosyltransferase that transfers an N-acetylglucosamine (GlcNAc) moiety onto the guanidino group of a target arginine, modulating host cell function. However, a lack of structural information has precluded elucidation of the molecular mechanisms in arginine and GlcNAc selection. We report here the crystal structure of SseK3 in its apo form and in complex with hydrolyzed UDP-GlcNAc. SseK3 possesses the typical glycosyltransferase type-A (GT-A)-family fold and the metal-coordinating DXD motif essential for ligand binding and enzymatic activity. Several conserved residues were essential for arginine GlcNAcylation and SseK3-mediated inhibition of NF-κB activation. Isothermal titration calorimetry revealed SseK3's preference for manganese coordination. The pattern of interactions in the substrate-bound SseK3 structure explained the selection of the primary ligand. Structural rearrangement of the C-terminal residues upon ligand binding was crucial for SseK3's catalytic activity, and NMR analysis indicated that SseK3 has limited UDP-GlcNAc hydrolysis activity. The release of free N-acetyl α-d-glucosamine, and the presence of the same molecule in the SseK3 active site, classified it as a retaining glycosyltransferase. A glutamate residue in the active site suggested a double-inversion mechanism for the arginine N-glycosylation reaction. Homology models of SseK1, SseK2, and the Escherichia coli orthologue NleB1 reveal differences in the surface electrostatic charge distribution, possibly accounting for their diverse activities. This first structure of a retaining GT-A arginine N-glycosyltransferase provides an important step toward a better understanding of this enzyme class and their roles as bacterial effectors.
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Affiliation(s)
- Diego Esposito
- From the Molecular Structure of Cell Signalling Laboratory, Francis Crick Institute, 1 Midland Road, London NW1 1AT, United Kingdom
| | - Regina A Günster
- the Section of Microbiology, Medical Research Council Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom, and
| | - Luigi Martino
- From the Molecular Structure of Cell Signalling Laboratory, Francis Crick Institute, 1 Midland Road, London NW1 1AT, United Kingdom
| | - Kamel El Omari
- the Diamond Light Source, Harwell Science and Innovation Campus, Chilton, Didcot OX11 0DE, United Kingdom
| | - Armin Wagner
- the Diamond Light Source, Harwell Science and Innovation Campus, Chilton, Didcot OX11 0DE, United Kingdom
| | - Teresa L M Thurston
- the Section of Microbiology, Medical Research Council Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom, and
| | - Katrin Rittinger
- From the Molecular Structure of Cell Signalling Laboratory, Francis Crick Institute, 1 Midland Road, London NW1 1AT, United Kingdom,
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12
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Cooperative Immune Suppression by Escherichia coli and Shigella Effector Proteins. Infect Immun 2018; 86:IAI.00560-17. [PMID: 29339461 DOI: 10.1128/iai.00560-17] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The enteric attaching and effacing (A/E) pathogens enterohemorrhagic Escherichia coli (EHEC) and enteropathogenic E. coli (EPEC) and the invasive pathogens enteroinvasive E. coli (EIEC) and Shigella encode type III secretion systems (T3SS) used to inject effector proteins into human host cells during infection. Among these are a group of effectors required for NF-κB-mediated host immune evasion. Recent studies have identified several effector proteins from A/E pathogens and EIEC/Shigella that are involved in suppression of NF-κB and have uncovered their cellular and molecular functions. A novel mechanism among these effectors from both groups of pathogens is to coordinate effector function during infection. This cooperativity among effector proteins explains how bacterial pathogens are able to effectively suppress innate immune defense mechanisms in response to diverse classes of immune receptor signaling complexes (RSCs) stimulated during infection.
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13
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Abstract
Glycosylation is a universal strategy to posttranslationally modify proteins. The recently discovered arginine rhamnosylation activates the polyproline-specific bacterial translation elongation factor EF-P. EF-P is rhamnosylated on arginine 32 by the glycosyltransferase EarP. However, the enzymatic mechanism remains elusive. In the present study, we solved the crystal structure of EarP from Pseudomonas putida. The enzyme is composed of two opposing domains with Rossmann folds, thus constituting a B pattern-type glycosyltransferase (GT-B). While dTDP-β-l-rhamnose is located within a highly conserved pocket of the C-domain, EarP recognizes the KOW-like N-domain of EF-P. Based on our data, we propose a structural model for arginine glycosylation by EarP. As EarP is essential for pathogenicity in P. aeruginosa, our study provides the basis for targeted inhibitor design. The structural and biochemical characterization of the EF-P-specific rhamnosyltransferase EarP not only provides the first molecular insights into arginine glycosylation but also lays the basis for targeted-inhibitor design against Pseudomonas aeruginosa infection.
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14
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Scott NE, Giogha C, Pollock GL, Kennedy CL, Webb AI, Williamson NA, Pearson JS, Hartland EL. The bacterial arginine glycosyltransferase effector NleB preferentially modifies Fas-associated death domain protein (FADD). J Biol Chem 2017; 292:17337-17350. [PMID: 28860194 DOI: 10.1074/jbc.m117.805036] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Revised: 08/28/2017] [Indexed: 01/01/2023] Open
Abstract
The inhibition of host innate immunity pathways is essential for the persistence of attaching and effacing pathogens such as enteropathogenic Escherichia coli (EPEC) and Citrobacter rodentium during mammalian infections. To subvert these pathways and suppress the antimicrobial response, attaching and effacing pathogens use type III secretion systems to introduce effectors targeting key signaling pathways in host cells. One such effector is the arginine glycosyltransferase NleB1 (NleBCR in C. rodentium) that modifies conserved arginine residues in death domain-containing host proteins with N-acetylglucosamine (GlcNAc), thereby blocking extrinsic apoptosis signaling. Ectopically expressed NleB1 modifies the host proteins Fas-associated via death domain (FADD), TNFRSF1A-associated via death domain (TRADD), and receptor-interacting serine/threonine protein kinase 1 (RIPK1). However, the full repertoire of arginine GlcNAcylation induced by pathogen-delivered NleB1 is unknown. Using an affinity proteomic approach for measuring arginine-GlcNAcylated glycopeptides, we assessed the global profile of arginine GlcNAcylation during ectopic expression of NleB1, EPEC infection in vitro, or C. rodentium infection in vivo NleB overexpression resulted in arginine GlcNAcylation of multiple host proteins. However, NleB delivery during EPEC and C. rodentium infection caused rapid and preferential modification of Arg117 in FADD. This FADD modification was extremely stable and insensitive to physiological temperatures, glycosidases, or host cell degradation. Despite its stability and effect on the inhibition of apoptosis, arginine GlcNAcylation did not elicit any proteomic changes, even in response to prolonged NleB1 expression. We conclude that, at normal levels of expression during bacterial infection, NleB1/NleBCR antagonizes death receptor-induced apoptosis of infected cells by modifying FADD in an irreversible manner.
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Affiliation(s)
- Nichollas E Scott
- From the Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne 3000, Australia,
| | - Cristina Giogha
- From the Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne 3000, Australia
| | - Georgina L Pollock
- From the Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne 3000, Australia
| | - Catherine L Kennedy
- From the Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne 3000, Australia
| | - Andrew I Webb
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Melbourne, Australia.,the Department of Medical Biology, University of Melbourne, Parkville, Victoria 3050, Australia, and
| | - Nicholas A Williamson
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria 3010, Australia
| | - Jaclyn S Pearson
- From the Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne 3000, Australia
| | - Elizabeth L Hartland
- From the Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne 3000, Australia
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15
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El Qaidi S, Chen K, Halim A, Siukstaite L, Rueter C, Hurtado-Guerrero R, Clausen H, Hardwidge PR. NleB/SseK effectors from Citrobacter rodentium, Escherichia coli, and Salmonella enterica display distinct differences in host substrate specificity. J Biol Chem 2017; 292:11423-11430. [PMID: 28522607 DOI: 10.1074/jbc.m117.790675] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 05/09/2017] [Indexed: 01/05/2023] Open
Abstract
Many Gram-negative bacterial pathogens use a syringe-like apparatus called a type III secretion system to inject virulence factors into host cells. Some of these effectors are enzymes that modify host proteins to subvert their normal functions. NleB is a glycosyltransferase that modifies host proteins with N-acetyl-d-glucosamine to inhibit antibacterial and inflammatory host responses. NleB is conserved among the attaching/effacing pathogens enterohemorrhagic Escherichia coli (EHEC), enteropathogenic E. coli (EPEC), and Citrobacter rodentium Moreover, Salmonella enterica strains encode up to three NleB orthologs named SseK1, SseK2, and SseK3. However, there are conflicting reports regarding the activities and host protein targets among the NleB/SseK orthologs. Therefore, here we performed in vitro glycosylation assays and cell culture experiments to compare the activities and substrate specificities of these effectors. SseK1, SseK3, EHEC NleB1, EPEC NleB1, and Crodentium NleB blocked TNF-mediated NF-κB pathway activation, whereas SseK2 and NleB2 did not. C. rodentium NleB, EHEC NleB1, and SseK1 glycosylated host GAPDH. C. rodentium NleB, EHEC NleB1, EPEC NleB1, and SseK2 glycosylated the FADD (Fas-associated death domain protein). SseK3 and NleB2 were not active against either substrate. We also found that EHEC NleB1 glycosylated two GAPDH arginine residues, Arg197 and Arg200, and that these two residues were essential for GAPDH-mediated activation of TNF receptor-associated factor 2 ubiquitination. These results provide evidence that members of this highly conserved family of bacterial virulence effectors target different host protein substrates and exhibit distinct cellular modes of action to suppress host responses.
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Affiliation(s)
- Samir El Qaidi
- From the College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506
| | - Kangming Chen
- From the College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506
| | - Adnan Halim
- the Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark.,the Laboratory of Cellular and Structural Biology, Rockefeller University, New York, New York 10065
| | - Lina Siukstaite
- the Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Christian Rueter
- the Institute of Infectiology, Center for Molecular Biology of Inflammation, University of Muenster, 48149 Muenster, Germany, and
| | - Ramon Hurtado-Guerrero
- the Fundacion ARAID, Edificio CEEI ARAGÓN and Institute of Biocomputation and Physics of Complex Systems, University of Zaragoza, Instituto de Quimica Fisica Rocasolano, Consejo Superior de Investigaciones Científicas Joint Unit, 500018 Zaragoza, Spain
| | - Henrik Clausen
- the Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Philip R Hardwidge
- From the College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506,
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16
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Distinct Roles of the Antiapoptotic Effectors NleB and NleF from Enteropathogenic Escherichia coli. Infect Immun 2017; 85:IAI.01071-16. [PMID: 28138023 DOI: 10.1128/iai.01071-16] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 01/25/2017] [Indexed: 11/20/2022] Open
Abstract
During infection, enteropathogenic Escherichia coli (EPEC) translocates effector proteins directly into the cytosol of infected enterocytes using a type III secretion system (T3SS). Once inside the host cell, these effector proteins subvert various immune signaling pathways, including death receptor-induced apoptosis. One such effector protein is the non-locus of enterocyte effacement (LEE)-encoded effector NleB1, which inhibits extrinsic apoptotic signaling via the FAS death receptor. NleB1 transfers a single N-acetylglucosamine (GlcNAc) residue to Arg117 in the death domain of Fas-associated protein with death domain (FADD) and inhibits FAS ligand (FasL)-stimulated caspase-8 cleavage. Another effector secreted by the T3SS is NleF. Previous studies have shown that NleF binds to and inhibits the activity of caspase-4, -8, and -9 in vitro Here, we investigated a role for NleF in the inhibition of FAS signaling and apoptosis during EPEC infection. We show that NleF prevents the cleavage of caspase-8, caspase-3, and receptor-interacting serine/threonine protein kinase 1 (RIPK1) in response to FasL stimulation. When translocated into host cells by the T3SS or expressed ectopically, NleF also blocked FasL-induced cell death. Using the EPEC-like mouse pathogen Citrobacter rodentium, we found that NleB but not NleF contributed to colonization of mice in the intestine. Hence, despite their shared ability to block FasL/FAS signaling, NleB and NleF have distinct roles during infection.
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17
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Pearson JS, Giogha C, Wong Fok Lung T, Hartland EL. The Genetics of EnteropathogenicEscherichia coliVirulence. Annu Rev Genet 2016; 50:493-513. [DOI: 10.1146/annurev-genet-120215-035138] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jaclyn S. Pearson
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3010, Australia; , , ,
| | - Cristina Giogha
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3010, Australia; , , ,
| | - Tania Wong Fok Lung
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3010, Australia; , , ,
| | - Elizabeth L. Hartland
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3010, Australia; , , ,
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18
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Gao X, Pham TH, Feuerbacher LA, Chen K, Hays MP, Singh G, Rueter C, Hurtado-Guerrero R, Hardwidge PR. Citrobacter rodentium NleB Protein Inhibits Tumor Necrosis Factor (TNF) Receptor-associated Factor 3 (TRAF3) Ubiquitination to Reduce Host Type I Interferon Production. J Biol Chem 2016; 291:18232-8. [PMID: 27387501 PMCID: PMC5000071 DOI: 10.1074/jbc.m116.738278] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 06/14/2016] [Indexed: 11/06/2022] Open
Abstract
Interferon signaling plays important roles in both intestinal homeostasis and in the host response to pathogen infection. The extent to which bacterial pathogens inhibit this host pathway is an understudied area of investigation. We characterized Citrobacter rodentium strains bearing deletions in individual type III secretion system effector genes to determine whether this pathogen inhibits the host type I IFN response and which effector is responsible. The NleB effector limited host IFN-β production by inhibiting Lys(63)-linked ubiquitination of TNF receptor-associated factor 3 (TRAF3). Inhibition was dependent on the glycosyltransferase activity of NleB. GAPDH, a target of NleB during infection, bound to TRAF3 and was required for maximal TRAF3 ubiquitination. NleB glycosyltransferase activity inhibited GAPDH-TRAF3 binding, resulting in reduced TRAF3 ubiquitination. Collectively, our data reveal important interplay between GAPDH and TRAF3 and suggest a mechanism by which the NleB effector inhibits type I IFN signaling.
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Affiliation(s)
- Xiaofei Gao
- From the Whitehead Institute, Cambridge, Massachusetts 02142
| | - Thanh H Pham
- Case Western Reserve University, Cleveland, Ohio 44106
| | - Leigh Ann Feuerbacher
- the College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506
| | - Kangming Chen
- the College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506
| | - Michael P Hays
- the College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506
| | - Gyanendra Singh
- the National Institute of Occupational Health, Meghani Nagar, Ahmedabad 380016, Gujarat, India
| | - Christian Rueter
- the Institute of Infectiology, University of Münster, D-48149 Münster, Germany, and
| | - Ramon Hurtado-Guerrero
- the Fundacion ARAID, Edificio CEEI ARAGÓN and Institute of Biocomputation and Physics of Complex Systems (BIFI), University of Zaragoza, BIFI-IQFR (CSIC) Joint Unit, Mariano Esquillor s/n, Campus Rio Ebro, Edificio I+D, 50018 Zaragoza, Spain
| | - Philip R Hardwidge
- the College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506,
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