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Pena MM, Martins TZ, Teper D, Zamuner C, Alves HA, Ferreira H, Wang N, Ferro MIT, Ferro JA. EnvC Homolog Encoded by Xanthomonas citri subsp. citri Is Necessary for Cell Division and Virulence. Microorganisms 2024; 12:691. [PMID: 38674634 PMCID: PMC11051873 DOI: 10.3390/microorganisms12040691] [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: 10/09/2023] [Revised: 03/16/2024] [Accepted: 03/21/2024] [Indexed: 04/28/2024] Open
Abstract
Peptidoglycan hydrolases are enzymes responsible for breaking the peptidoglycan present in the bacterial cell wall, facilitating cell growth, cell division and peptidoglycan turnover. Xanthomonas citri subsp. citri (X. citri), the causal agent of citrus canker, encodes an Escherichia coli M23 peptidase EnvC homolog. EnvC is a LytM factor essential for cleaving the septal peptidoglycan, thereby facilitating the separation of daughter cells. In this study, the investigation focused on EnvC contribution to the virulence and cell separation of X. citri. It was observed that disruption of the X. citri envC gene (ΔenvC) led to a reduction in virulence. Upon inoculation into leaves of Rangpur lime (Citrus limonia Osbeck), the X. citri ΔenvC exhibited a delayed onset of citrus canker symptoms compared with the wild-type X. citri. Mutant complementation restored the wild-type phenotype. Sub-cellular localization confirmed that X. citri EnvC is a periplasmic protein. Moreover, the X. citri ΔenvC mutant exhibited elongated cells, indicating a defect in cell division. These findings support the role of EnvC in the regulation of cell wall organization, cell division, and they clarify the role of this peptidase in X. citri virulence.
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Affiliation(s)
- Michelle M. Pena
- Agricultural and Livestock Microbiology Graduation Program, School of Agricultural and Veterinarian Sciences, São Paulo State University (UNESP), Jaboticabal 14884-900, SP, Brazil; (M.M.P.); (T.Z.M.)
| | - Thaisa Z. Martins
- Agricultural and Livestock Microbiology Graduation Program, School of Agricultural and Veterinarian Sciences, São Paulo State University (UNESP), Jaboticabal 14884-900, SP, Brazil; (M.M.P.); (T.Z.M.)
| | - Doron Teper
- Department of Plant Pathology and Weed Research, Institute of Plant Protection Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel;
| | - Caio Zamuner
- Biochemistry Building, Institute of Biosciences, São Paulo State University (UNESP), Rio Claro 13506-900, SP, Brazil; (C.Z.); (H.F.)
| | - Helen A. Alves
- Department of Agricultural, Livestock and Environmental Biotechnology, School of Agricultural and Veterinary Sciences, São Paulo State University (UNESP), Jaboticabal 14884-900, SP, Brazil; (H.A.A.); (M.I.T.F.)
| | - Henrique Ferreira
- Biochemistry Building, Institute of Biosciences, São Paulo State University (UNESP), Rio Claro 13506-900, SP, Brazil; (C.Z.); (H.F.)
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850, USA;
| | - Maria Inês T. Ferro
- Department of Agricultural, Livestock and Environmental Biotechnology, School of Agricultural and Veterinary Sciences, São Paulo State University (UNESP), Jaboticabal 14884-900, SP, Brazil; (H.A.A.); (M.I.T.F.)
| | - Jesus A. Ferro
- Department of Agricultural, Livestock and Environmental Biotechnology, School of Agricultural and Veterinary Sciences, São Paulo State University (UNESP), Jaboticabal 14884-900, SP, Brazil; (H.A.A.); (M.I.T.F.)
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2
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Izquierdo-Martinez A, Billini M, Miguel-Ruano V, Hernández-Tamayo R, Richter P, Biboy J, Batuecas MT, Glatter T, Vollmer W, Graumann PL, Hermoso JA, Thanbichler M. DipM controls multiple autolysins and mediates a regulatory feedback loop promoting cell constriction in Caulobacter crescentus. Nat Commun 2023; 14:4095. [PMID: 37433794 DOI: 10.1038/s41467-023-39783-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 06/22/2023] [Indexed: 07/13/2023] Open
Abstract
Proteins with a catalytically inactive LytM-type endopeptidase domain are important regulators of cell wall-degrading enzymes in bacteria. Here, we study their representative DipM, a factor promoting cell division in Caulobacter crescentus. We show that the LytM domain of DipM interacts with multiple autolysins, including the soluble lytic transglycosylases SdpA and SdpB, the amidase AmiC and the putative carboxypeptidase CrbA, and stimulates the activities of SdpA and AmiC. Its crystal structure reveals a conserved groove, which is predicted to represent the docking site for autolysins by modeling studies. Mutations in this groove indeed abolish the function of DipM in vivo and its interaction with AmiC and SdpA in vitro. Notably, DipM and its targets SdpA and SdpB stimulate each other's recruitment to midcell, establishing a self-reinforcing cycle that gradually increases autolytic activity as cytokinesis progresses. DipM thus coordinates different peptidoglycan-remodeling pathways to ensure proper cell constriction and daughter cell separation.
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Affiliation(s)
- Adrian Izquierdo-Martinez
- Department of Biology, University of Marburg, Marburg, Germany
- Max Planck Fellow Group Bacterial Cell Biology, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
- Bacterial Cell Biology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Maria Billini
- Department of Biology, University of Marburg, Marburg, Germany
| | - Vega Miguel-Ruano
- Department of Crystallography and Structural Biology, Instituto de Química-Física "Rocasolano", Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Rogelio Hernández-Tamayo
- Department of Chemistry, University of Marburg, Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Pia Richter
- Department of Biology, University of Marburg, Marburg, Germany
| | - Jacob Biboy
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - María T Batuecas
- Department of Crystallography and Structural Biology, Instituto de Química-Física "Rocasolano", Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Timo Glatter
- Mass Spectrometry and Proteomics Facility, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia
| | - Peter L Graumann
- Department of Chemistry, University of Marburg, Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Juan A Hermoso
- Department of Crystallography and Structural Biology, Instituto de Química-Física "Rocasolano", Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Martin Thanbichler
- Department of Biology, University of Marburg, Marburg, Germany.
- Max Planck Fellow Group Bacterial Cell Biology, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany.
- Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany.
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3
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Revealing novel synergistic defense and acid tolerant performance of Escherichia coli in response to organic acid stimulation. Appl Microbiol Biotechnol 2022; 106:7577-7594. [DOI: 10.1007/s00253-022-12241-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 10/04/2022] [Accepted: 10/12/2022] [Indexed: 11/06/2022]
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4
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Thompson C, George S, White ML, Eswara PJ, Ouyang Z. BB0761, a MepM homolog, contributes to Borrelia burgdorferi cell division and mammalian infectivity. Mol Microbiol 2022; 117:1405-1418. [PMID: 35510701 PMCID: PMC9794411 DOI: 10.1111/mmi.14916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 05/01/2022] [Accepted: 05/02/2022] [Indexed: 12/30/2022]
Abstract
M23 family endopeptidases play important roles in cell division and separation in a wide variety of bacteria. Recent studies have suggested that these proteins also contribute to bacterial virulence. However, the biological function of M23 peptidases in pathogenic spirochetes remains unexplored. Here, we describe Borrelia burgdorferi, the bacterial pathogen causing Lyme disease, requires a putative M23 family homolog, BB0761, for spirochete morphology and cell division. Indeed, the inactivation of bb0761 led to an aberrant filamentous phenotype as well as the impairment of B. burgdorferi growth in vitro. These phenotypes were complemented not only with B. burgdorferi bb0761, but also with the mepM gene from E. coli. Moreover, the bb0761 mutant showed a complete loss of infectivity in a murine model of Lyme borreliosis. Resistance of the mutant to osmotic and oxidative stresses was markedly reduced. Our combined results indicate that BB0761 contributes to B. burgdorferi cell division and virulence.
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Affiliation(s)
- Christina Thompson
- Department of Molecular Medicine, University of South Florida, Tampa, Florida, USA
| | - Sierra George
- Department of Molecular Medicine, University of South Florida, Tampa, Florida, USA
| | - Maria L. White
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, Florida, USA
| | - Prahathees J. Eswara
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, Florida, USA
| | - Zhiming Ouyang
- Department of Molecular Medicine, University of South Florida, Tampa, Florida, USA
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5
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Abstract
Peptidoglycan is a major constituent of the bacterial cell wall and an important determinant for providing protection to cells. In addition to peptidoglycan, many bacteria synthesize other glycans that become part of the cell wall. Streptomycetes grow apically, where they synthesize a glycan that is exposed at the outer surface, but how it gets there is unknown. Here, we show that deposition of the apical glycan at the cell surface of Streptomyces coelicolor depends on two key enzymes, the glucanase CslZ and the lytic polysaccharide monooxygenase LpmP. Activity of these enzymes allows localized remodeling and degradation of the peptidoglycan, and we propose that this facilitates passage of the glycan. The absence of both enzymes not only prevents morphological development but also sensitizes strains to lysozyme. Given that lytic polysaccharide monooxygenases are commonly found in microbes, this newly identified biological role in cell wall remodeling may be widespread.
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Mandela E, Stubenrauch CJ, Ryoo D, Hwang H, Cohen EJ, Torres VVL, Deo P, Webb CT, Huang C, Schittenhelm RB, Beeby M, Gumbart JC, Lithgow T, Hay ID. Adaptation of the periplasm to maintain spatial constraints essential for cell envelope processes and cell viability. eLife 2022; 11:73516. [PMID: 35084330 PMCID: PMC8824477 DOI: 10.7554/elife.73516] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 01/21/2022] [Indexed: 11/17/2022] Open
Abstract
The cell envelope of Gram-negative bacteria consists of two membranes surrounding a periplasm and peptidoglycan layer. Molecular machines spanning the cell envelope depend on spatial constraints and load-bearing forces across the cell envelope and surface. The mechanisms dictating spatial constraints across the cell envelope remain incompletely defined. In Escherichia coli, the coiled-coil lipoprotein Lpp contributes the only covalent linkage between the outer membrane and the underlying peptidoglycan layer. Using proteomics, molecular dynamics, and a synthetic lethal screen, we show that lengthening Lpp to the upper limit does not change the spatial constraint but is accommodated by other factors which thereby become essential for viability. Our findings demonstrate E. coli expressing elongated Lpp does not simply enlarge the periplasm in response, but the bacteria accommodate by a combination of tilting Lpp and reducing the amount of the covalent bridge. By genetic screening, we identified all of the genes in E. coli that become essential in order to enact this adaptation, and by quantitative proteomics discovered that very few proteins need to be up- or down-regulated in steady-state levels in order to accommodate the longer Lpp. We observed increased levels of factors determining cell stiffness, a decrease in membrane integrity, an increased membrane vesiculation and a dependance on otherwise non-essential tethers to maintain lipid transport and peptidoglycan biosynthesis. Further this has implications for understanding how spatial constraint across the envelope controls processes such as flagellum-driven motility, cellular signaling, and protein translocation
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Affiliation(s)
- Eric Mandela
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | | | - David Ryoo
- Interdisciplinary Bioengineering Graduate Program, Georgia Institute of Technology, Atlanta, United States
| | - Hyea Hwang
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States
| | - Eli J Cohen
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | | | - Pankaj Deo
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Chaille T Webb
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Cheng Huang
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Ralf B Schittenhelm
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Morgan Beeby
- Department of Life Sciencesa, Imperial College London, London, United Kingdom
| | - James C Gumbart
- School of Physics, Georgia Institute of Technology, Atlanta, United States
| | - Trevor Lithgow
- Department of Microbiology, Monash University, Melbourne, Australia
| | - Iain D Hay
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand
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7
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Figueroa-Cuilan WM, Randich AM, Dunn CM, Santiago-Collazo G, Yowell A, Brown PJB. Diversification of LytM Protein Functions in Polar Elongation and Cell Division of Agrobacterium tumefaciens. Front Microbiol 2021; 12:729307. [PMID: 34489918 PMCID: PMC8416486 DOI: 10.3389/fmicb.2021.729307] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 07/26/2021] [Indexed: 12/05/2022] Open
Abstract
LytM-domain containing proteins are LAS peptidases (lysostaphin-type enzymes, D-Ala-D-Ala metallopeptidases, and sonic hedgehog) and are known to play diverse roles throughout the bacterial cell cycle through direct or indirect hydrolysis of the bacterial cell wall. A subset of the LytM factors are catalytically inactive but regulate the activity of other cell wall hydrolases and are classically described as cell separation factors NlpD and EnvC. Here, we explore the function of four LytM factors in the alphaproteobacterial plant pathogen Agrobacterium tumefaciens. An LmdC ortholog (Atu1832) and a MepM ortholog (Atu4178) are predicted to be catalytically active. While Atu1832 does not have an obvious function in cell growth or division, Atu4178 is essential for polar growth and likely functions as a space-making endopeptidase that cleaves amide bonds in the peptidoglycan cell wall during elongation. The remaining LytM factors are degenerate EnvC and NlpD orthologs. Absence of these proteins results in striking phenotypes indicative of misregulation of cell division and growth pole establishment. The deletion of an amidase, AmiC, closely phenocopies the deletion of envC suggesting that EnvC might regulate AmiC activity. The NlpD ortholog DipM is unprecedently essential for viability and depletion results in the misregulation of early stages of cell division, contrasting with the canonical view of DipM as a cell separation factor. Finally, we make the surprising observation that absence of AmiC relieves the toxicity induced by dipM overexpression. Together, these results suggest EnvC and DipM may function as regulatory hubs with multiple partners to promote proper cell division and establishment of polarity.
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Affiliation(s)
| | - Amelia M. Randich
- Department of Biology, University of Scranton, Scranton, PA, United States
| | - Caroline M. Dunn
- Division of Biological Sciences, University of Missouri, Columbia, MO, United States
| | - Gustavo Santiago-Collazo
- Division of Biological Sciences, University of Missouri, Columbia, MO, United States
- Molecular Pathogenesis and Therapeutics Graduate Program, University of Missouri, Columbia, MO, United States
| | - Andrew Yowell
- Division of Biological Sciences, University of Missouri, Columbia, MO, United States
| | - Pamela J. B. Brown
- Division of Biological Sciences, University of Missouri, Columbia, MO, United States
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8
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Gan YL, Yang LY, Yang LC, Li WL, Liang XL, Jiang W, Jiang GF, Hang XH, Yang M, Tang JL, Jiang BL. The C-terminal domain of the type III secretion chaperone HpaB contributes to dissociation of chaperone-effector complex in Xanthomonas campestris pv. campestris. PLoS One 2021; 16:e0246033. [PMID: 33507993 PMCID: PMC7842900 DOI: 10.1371/journal.pone.0246033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 01/12/2021] [Indexed: 12/01/2022] Open
Abstract
Many animal and plant pathogenic bacteria employ a type three secretion system (T3SS) to deliver type three effector proteins (T3Es) into host cells. Efficient secretion of many T3Es in the plant pathogen Xanthomonas campestris pv. campestris (Xcc) relies on the global chaperone HpaB. However, how the domain of HpaB itself affects effector translocation/secretion is poorly understood. Here, we used genetic and biochemical approaches to identify a novel domain at the C-terminal end of HpaB (amino acid residues 137-160) that contributes to virulence and hypersensitive response (HR). Both in vitro secretion assay and in planta translocation assay showed that the secretion and translocation of T3E proteins depend on the C-terminal region of HpaB. Deletion of the C-terminal region of HpaB did not affect binding to T3Es, self-association or interaction with T3SS components. However, the deletion of C-terminal region sharply reduced the mounts of free T3Es liberated from the complex of HpaB with the T3Es, a reaction catalyzed in an ATP-dependent manner by the T3SS-associated ATPase HrcN. Our findings demonstrate the C-terminal domain of HpaB contributes to disassembly of chaperone-effector complex and reveal a potential molecular mechanism underpinning the involvement of HpaB in secretion of T3Es in Xcc.
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Affiliation(s)
- Yong-Liang Gan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Li-Yan Yang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Li-Chao Yang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Wan-Lian Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Xue-Lian Liang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Wei Jiang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | | | - Xiao-Hong Hang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Mei Yang
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning, China
| | - Ji-Liang Tang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Bo-Le Jiang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
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9
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Stable inheritance of Sinorhizobium meliloti cell growth polarity requires an FtsN-like protein and an amidase. Nat Commun 2021; 12:545. [PMID: 33483499 PMCID: PMC7822825 DOI: 10.1038/s41467-020-20739-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 12/17/2020] [Indexed: 12/12/2022] Open
Abstract
In Rhizobiales bacteria, such as Sinorhizobium meliloti, cell elongation takes place only at new cell poles, generated by cell division. Here, we show that the role of the FtsN-like protein RgsS in S. meliloti extends beyond cell division. RgsS contains a conserved SPOR domain known to bind amidase-processed peptidoglycan. This part of RgsS and peptidoglycan amidase AmiC are crucial for reliable selection of the new cell pole as cell elongation zone. Absence of these components increases mobility of RgsS molecules, as well as abnormal RgsS accumulation and positioning of the growth zone at the old cell pole in about one third of the cells. These cells with inverted growth polarity are able to complete the cell cycle but show partially impaired chromosome segregation. We propose that amidase-processed peptidoglycan provides a landmark for RgsS to generate cell polarity in unipolarly growing Rhizobiales. In Sinorhizobium bacteria, cell elongation takes place only at new cell poles, generated by cell division. Here, Krol et al. show that an FtsN-like protein and a peptidoglycan amidase are crucial for reliable selection of the new cell pole as cell elongation zone.
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10
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Ji X, Lu P, Xue J, Zhao N, Zhang Y, Dong L, Zhang X, Li P, Hu Y, Wang J, Zhang B, Liu J, Lv H, Wang S. The lipoprotein NlpD in Cronobacter sakazakii responds to acid stress and regulates macrophage resistance and virulence by maintaining membrane integrity. Virulence 2021; 12:415-429. [PMID: 33459158 PMCID: PMC7834084 DOI: 10.1080/21505594.2020.1870336] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Cronobacter sakazakii, an emerging opportunistic pathogen, is implicated in severe foodborne outbreak infections in premature and full-term infants. Generally, acid tolerance is vital for the pathogenesis of foodborne pathogens; however, its role in C. sakazakii virulence remains largely unknown. To screen out acid-tolerance determinants from transposon mutants, anovel counterselection method using gentamicin and acid was developed. Using the counterselection method and growth assay, we screened several acid-sensitive mutants and found that nlpD encodes an acid-resistance factor in C. sakazakii. Compared to the wild-type strain, the nlpD mutant exhibited attenuated virulence in a rat model. Using macrophage THP-1 cells and a pH probe, we verified that nlpD enables bacteria to resist macrophages by resisting acidification. Finally, we confirmed that nlpD maintains C. sakazakii membrane integrity in acid using propidium iodide permeabilization assays via flow cytometry. Our results confirm that nlpD is a novel virulence factor that permits C. sakazakii to survive under acid stress conditions. Considering that NlpD is a conserved lipoprotein located in the bacterial outer membrane, NlpD could be used as a target for drug development.
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Affiliation(s)
- Xuemeng Ji
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Ping Lu
- Institute of Radiation Medicine, Chinese Academy of Medical Science and Peking Union Medical Collage , Tianjin, China
| | - Juan Xue
- Institute of Infection and Immunity, Taihe Hospital, Hubei University of Medicine , Shiyan, China
| | - Ning Zhao
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Yan Zhang
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Lu Dong
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Xuejiao Zhang
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Ping Li
- Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology , Tianjin, China
| | - Yaozhong Hu
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Jin Wang
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Bowei Zhang
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Jingmin Liu
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Huan Lv
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
| | - Shuo Wang
- Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University , Tianjin, China
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11
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Orellana CA, Zaragoza NE, Licona-Cassani C, Palfreyman RW, Cowie N, Moonen G, Moutafis G, Power J, Nielsen LK, Marcellin E. Time-course transcriptomics reveals that amino acids catabolism plays a key role in toxinogenesis and morphology in Clostridium tetani. ACTA ACUST UNITED AC 2020; 47:1059-1073. [DOI: 10.1007/s10295-020-02330-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 11/02/2020] [Indexed: 10/23/2022]
Abstract
Abstract
Tetanus is a fatal disease caused by Clostridium tetani infections. To prevent infections, a toxoid vaccine, developed almost a century ago, is routinely used in humans and animals. The vaccine is listed in the World Health Organisation list of Essential Medicines and can be produced and administered very cheaply in the developing world for less than one US Dollar per dose. Recent developments in both analytical tools and frameworks for systems biology provide industry with an opportunity to gain a deeper understanding of the parameters that determine C. tetani virulence and physiological behaviour in bioreactors. Here, we compared a traditional fermentation process with a fermentation medium supplemented with five heavily consumed amino acids. The experiment demonstrated that amino acid catabolism plays a key role in the virulence of C. tetani. The addition of the five amino acids favoured growth, decreased toxin production and changed C. tetani morphology. Using time-course transcriptomics, we created a “fermentation map”, which shows that the tetanus toxin transcriptional regulator BotR, P21 and the tetanus toxin gene was downregulated. Moreover, this in-depth analysis revealed potential genes that might be involved in C. tetani virulence regulation. We observed differential expression of genes related to cell separation, surface/cell adhesion, pyrimidine biosynthesis and salvage, flagellar motility, and prophage genes. Overall, the fermentation map shows that, mediated by free amino acid concentrations, virulence in C. tetani is regulated at the transcriptional level and affects a plethora of metabolic functions.
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Affiliation(s)
- Camila A Orellana
- grid.1003.2 0000 0000 9320 7537 Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland 4072 Brisbane QLD Australia
- grid.7870.8 0000 0001 2157 0406 Department of Chemical and Bioprocess Engineering, School of Engineering Pontificia Universidad Católica de Chile Santiago Chile
| | - Nicolas E Zaragoza
- grid.1003.2 0000 0000 9320 7537 Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland 4072 Brisbane QLD Australia
| | - Cuauhtemoc Licona-Cassani
- grid.1003.2 0000 0000 9320 7537 Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland 4072 Brisbane QLD Australia
- grid.419886.a 0000 0001 2203 4701 Centro de Biotecnología FEMSA Tecnológico de Monterrey Nuevo León Mexico
| | - Robin W Palfreyman
- grid.1003.2 0000 0000 9320 7537 Metabolomics Australia The University of Queensland 4072 Brisbane QLD Australia
| | - Nicholas Cowie
- grid.1003.2 0000 0000 9320 7537 Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland 4072 Brisbane QLD Australia
| | - Glenn Moonen
- Zoetis. 45 Poplar Road 3052 Parkville VIC Australia
| | | | - John Power
- Zoetis. 45 Poplar Road 3052 Parkville VIC Australia
| | - Lars K Nielsen
- grid.1003.2 0000 0000 9320 7537 Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland 4072 Brisbane QLD Australia
- grid.1003.2 0000 0000 9320 7537 Metabolomics Australia The University of Queensland 4072 Brisbane QLD Australia
- grid.5170.3 0000 0001 2181 8870 The Novo Nordisk Foundation Centre for Biosustainability Technical University of Denmark Kgs. Lyngby Denmark
| | - Esteban Marcellin
- grid.1003.2 0000 0000 9320 7537 Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland 4072 Brisbane QLD Australia
- grid.1003.2 0000 0000 9320 7537 Metabolomics Australia The University of Queensland 4072 Brisbane QLD Australia
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12
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A Peptidoglycan Amidase Activator Impacts Salmonella enterica Serovar Typhimurium Gut Infection. Infect Immun 2020; 88:IAI.00187-20. [PMID: 32284369 DOI: 10.1128/iai.00187-20] [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] [Received: 03/30/2020] [Accepted: 04/05/2020] [Indexed: 12/12/2022] Open
Abstract
Salmonella enterica serovar Typhimurium is an important foodborne pathogen that causes diarrhea. S. Typhimurium elicits inflammatory responses and colonizes the gut lumen by outcompeting the microbiota. Although evidence is accumulating with regard to the underlying mechanism, the infectious stage has not been adequately defined. Peptidoglycan amidases are widely distributed among bacteria and play a prominent role in peptidoglycan maintenance by hydrolyzing peptidoglycans. Amidase activation is required for the regulation of at least one of two cognate activators, NlpD or EnvC (also called YibP). Recent studies established that the peptidoglycan amidase AmiC-mediated cell division specifically confers a fitness advantage on S Typhimurium in the inflamed gut. However, it remains unknown which cognate activators are involved in the amidase activation and how the activators influence Salmonella sp. pathogenesis. Here, we characterize the role of two activators, NlpD and EnvC, in S Typhimurium cell division and gut infection. EnvC was found to contribute to cell division of S Typhimurium cells through the activation of AmiA and AmiC. The envC mutant exhibited impairments in gut infection, including a gut colonization defect and reduced ability to elicit inflammatory responses. Importantly, the colonization defect of the envC mutant was unrelated to the microbiota but was conferred by attenuated motility and chemotaxis of S Typhimurium cells, which were not observed in the amiA amiC mutant. Furthermore, the envC mutant was impaired in its induction of mucosal inflammation and sustained gut colonization. Collectively, our findings provide a novel insight into the peptidoglycan amidase/cognate activator circuits and their dependent pathogenesis.
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Zhu PC, Li YM, Yang X, Zou HF, Zhu XL, Niu XN, Xu LH, Jiang W, Huang S, Tang JL, He YQ. Type VI secretion system is not required for virulence on rice but for inter-bacterial competition in Xanthomonas oryzae pv. oryzicola. Res Microbiol 2019; 171:64-73. [PMID: 31676435 DOI: 10.1016/j.resmic.2019.10.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 10/17/2019] [Accepted: 10/17/2019] [Indexed: 11/28/2022]
Abstract
The type VI secretion system (T6SS), a multifunctional protein secretion device, plays very important roles in bacterial killing and/or virulence to eukaryotic cells. Although T6SS genes have been found in many Xanthomonas species, the biological function of T6SSs has not been elucidated in most xanthomonads. In this study, we identified two phylogenetically distinct T6SS clusters, T6SS1 and T6SS2, in a newly sequenced Chinese strain GX01 of Xanthomonas oryzea pv. oryzicola (Xoc) which causes bacterial leaf streak (BLS) of rice (Oryza sativa L.). Mutational assays demonstrated that T6SS1 and T6SS2 are not required for the virulence of Xoc GX01 on rice. Nevertheless, we found that T6SS2, but not T6SS1, played an important role in bacterial killing. Transcription and secretion analysis revealed that hcp2 gene is actively expressed and that Hcp2 protein is secreted via T6SS. Moreover, several candidate T6SS effectors were predicted by bioinformatics analysis that might play a role in the antibacterial activity of Xoc. This is the first report to investigate the type VI secretion system in Xanthomonas oryzae. We speculate that Xoc T6SS2 might play an important role in inter-bacterial competition, allowing this plant pathogen to gain niche advantage by killing other bacteria.
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Affiliation(s)
- Ping-Chuan Zhu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China
| | - Yi-Ming Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China
| | - Xia Yang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China
| | - Hai-Fan Zou
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China
| | - Xiao-Lin Zhu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China
| | - Xiang-Na Niu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China
| | - Ling-Hui Xu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China
| | - Wei Jiang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China
| | - Sheng Huang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China
| | - Ji-Liang Tang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China.
| | - Yong-Qiang He
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China; National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China.
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14
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Gallie J, Bertels F, Remigi P, Ferguson GC, Nestmann S, Rainey PB. Repeated Phenotypic Evolution by Different Genetic Routes in Pseudomonas fluorescens SBW25. Mol Biol Evol 2019; 36:1071-1085. [PMID: 30835268 PMCID: PMC6519391 DOI: 10.1093/molbev/msz040] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Repeated evolution of functionally similar phenotypes is observed throughout the tree of life. The extent to which the underlying genetics are conserved remains an area of considerable interest. Previously, we reported the evolution of colony switching in two independent lineages of Pseudomonas fluorescens SBW25. The phenotypic and genotypic bases of colony switching in the first lineage (Line 1) have been described elsewhere. Here, we deconstruct the evolution of colony switching in the second lineage (Line 6). We show that, as for Line 1, Line 6 colony switching results from an increase in the expression of a colanic acid-like polymer (CAP). At the genetic level, nine mutations occur in Line 6. Only one of these—a nonsynonymous point mutation in the housekeeping sigma factor rpoD—is required for colony switching. In contrast, the genetic basis of colony switching in Line 1 is a mutation in the metabolic gene carB. A molecular model has recently been proposed whereby the carB mutation increases capsulation by redressing the intracellular balance of positive (ribosomes) and negative (RsmAE/CsrA) regulators of a positive feedback loop in capsule expression. We show that Line 6 colony switching is consistent with this model; the rpoD mutation generates an increase in ribosomal gene expression, and ultimately an increase in CAP expression.
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Affiliation(s)
- Jenna Gallie
- Department of Evolutionary Theory, Max Planck Institute for Evolutionary Biology, Plön, Germany.,New Zealand Institute for Advanced Study, Massey University at Albany, Auckland, New Zealand
| | - Frederic Bertels
- New Zealand Institute for Advanced Study, Massey University at Albany, Auckland, New Zealand.,Department of Microbial Population Biology, Max Planck Institute for Evolutionary Biology, Plön, Germany
| | - Philippe Remigi
- New Zealand Institute for Advanced Study, Massey University at Albany, Auckland, New Zealand.,Laboratoire des Interactions Plantes-Microorganismes (LIPM), Université de Toulouse, INRA, CNRS, Castanet-Tolosan, France
| | - Gayle C Ferguson
- School of Natural and Computational Sciences, Massey University at Albany, Auckland, New Zealand
| | - Sylke Nestmann
- New Zealand Institute for Advanced Study, Massey University at Albany, Auckland, New Zealand
| | - Paul B Rainey
- New Zealand Institute for Advanced Study, Massey University at Albany, Auckland, New Zealand.,Department of Microbial Population Biology, Max Planck Institute for Evolutionary Biology, Plön, Germany.,Ecole Supérieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI ParisTech), CNRS UMR 8231, PSL Research University, Paris, France
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15
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Juan C, Torrens G, Barceló IM, Oliver A. Interplay between Peptidoglycan Biology and Virulence in Gram-Negative Pathogens. Microbiol Mol Biol Rev 2018; 82:e00033-18. [PMID: 30209071 PMCID: PMC6298613 DOI: 10.1128/mmbr.00033-18] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The clinical and epidemiological threat of the growing antimicrobial resistance in Gram-negative pathogens, particularly for β-lactams, the most frequently used and relevant antibiotics, urges research to find new therapeutic weapons to combat the infections caused by these microorganisms. An essential previous step in the development of these therapeutic solutions is to identify their potential targets in the biology of the pathogen. This is precisely what we sought to do in this review specifically regarding the barely exploited field analyzing the interplay among the biology of the peptidoglycan and related processes, such as β-lactamase regulation and virulence. Hence, here we gather, analyze, and integrate the knowledge derived from published works that provide information on the topic, starting with those dealing with the historically neglected essential role of the Gram-negative peptidoglycan in virulence, including structural, biogenesis, remodeling, and recycling aspects, in addition to proinflammatory and other interactions with the host. We also review the complex link between intrinsic β-lactamase production and peptidoglycan metabolism, as well as the biological costs potentially associated with the expression of horizontally acquired β-lactamases. Finally, we analyze the existing evidence from multiple perspectives to provide useful clues for identifying targets enabling the future development of therapeutic options attacking the peptidoglycan-virulence interconnection as a key weak point of the Gram-negative pathogens to be used, if not to kill the bacteria, to mitigate their capacity to produce severe infections.
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Affiliation(s)
- Carlos Juan
- Servicio de Microbiología and Unidad de Investigación, Hospital Son Espases, Instituto de Investigación Sanitaria de Baleares (IdISBa), Palma, Spain
| | - Gabriel Torrens
- Servicio de Microbiología and Unidad de Investigación, Hospital Son Espases, Instituto de Investigación Sanitaria de Baleares (IdISBa), Palma, Spain
| | - Isabel Maria Barceló
- Servicio de Microbiología and Unidad de Investigación, Hospital Son Espases, Instituto de Investigación Sanitaria de Baleares (IdISBa), Palma, Spain
| | - Antonio Oliver
- Servicio de Microbiología and Unidad de Investigación, Hospital Son Espases, Instituto de Investigación Sanitaria de Baleares (IdISBa), Palma, Spain
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