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Fierros CH, Faucillion ML, Hahn BL, Anderson P, Bonde M, Kessler JR, Surdel MC, Crawford KS, Gao Y, Zhu J, Bergström S, Coburn J. Borrelia burgdorferi tolerates alteration to P66 porin function in a murine infectivity model. Front Cell Infect Microbiol 2025; 14:1528456. [PMID: 39906208 PMCID: PMC11790652 DOI: 10.3389/fcimb.2024.1528456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2024] [Accepted: 12/26/2024] [Indexed: 02/06/2025] Open
Abstract
Borrelia burgdorferi exists in a complex enzootic life cycle requiring differential gene regulation. P66, a porin and adhesin, is upregulated and essential during mammalian infection, but is not produced or required within the tick vector. We sought to determine whether the porin function of P66 is essential for infection. Vancomycin treatment of B. burgdorferi cultures was used to screen for P66 porin function and found to generate spontaneous mutations in p66 (bb0603). Three novel, spontaneous, missense P66 mutants (G175V, T176M, and G584R) were re-created by site-directed mutagenesis in an infectious strain background and tested for infectivity in mice by ID50 experiments. Two of the three mutants retained infectivity comparable to the isogenic control, suggesting that B. burgdorferi can tolerate alteration to P66 porin function during infection. The third mutant exhibited highly attenuated infectivity and produced low levels of P66 protein. Interestingly, four isolates that were recovered for p66 sequencing from mouse tissues revealed novel secondary point mutations in genomic p66. However, these secondary mutations did not rescue P66 porin function. New structural modeling of P66 is presented and consistent with these experimental results. This is the first work to assess the contribution of P66 porin function to B. burgdorferi pathogenesis.
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Affiliation(s)
- Christa H. Fierros
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States
| | | | - Beth L. Hahn
- Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Phillip Anderson
- Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Mari Bonde
- Department of Molecular Biology, Umeå University, Umea, Sweden
| | - Julie R. Kessler
- Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Matthew C. Surdel
- Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Kyler S. Crawford
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Yan Gao
- Division of Biostatistics, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Jieqing Zhu
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States
- Department of Biochemistry, Medical College of Wisconsin, Versiti Blood Research Institute, Milwaukee, WI, United States
| | - Sven Bergström
- Department of Molecular Biology, Umeå University, Umea, Sweden
| | - Jenifer Coburn
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States
- Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, United States
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He J, Lin X, Zhang D, Hu H, Chen X, Xu F, Zhou M. Wake biofilm up to enhance suicidal uptake of gallium for chronic lung infection treatment. Biomaterials 2024; 310:122619. [PMID: 38805955 DOI: 10.1016/j.biomaterials.2024.122619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 05/05/2024] [Accepted: 05/16/2024] [Indexed: 05/30/2024]
Abstract
The hypometabolic and nutrient-limiting condition of dormant bacteria inside biofilms reduces their susceptibility to antibacterial agents, making the treatment of biofilm-dominating chronic infections difficult. Herein, we demonstrate an intratracheal aerosolized maltohexaose-modified catalase-gallium integrated nanosystem that can 'wake up' dormant Pseudomonas aeruginosa biofilm to increase the metabolism and nutritional iron demand by reconciling the oxygen gradient. The activated bacteria then enhance suicidal gallium uptake since gallium acts as a 'Trojan horse' to mimic iron. The internalized gallium ions disrupt biofilms by interfering with the physiological processes of iron ion acquisition and utilization, biofilm formation, and quorum sensing. Furthermore, aerosol microsprayer administration and bacteria-specific maltohexaose modification enable accumulation at biofilm-infected lung and targeted release of gallium into bacteria to improve the therapeutic effect. This work provides a potential strategy for treating infection by reversing the dormant biofilm's resistance condition.
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Affiliation(s)
- Jian He
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China; Institute of Translational Medicine, Zhejiang University, Hangzhou, 310029, China
| | - Xiuhui Lin
- Department of Infectious Diseases, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China
| | - Dongxiao Zhang
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China; Zhejiang University-University of Edinburgh Institute (ZJU-UoE Institute), Zhejiang University School of Medicine, Zhejiang University, Haining, 314400, China
| | - Huiqun Hu
- Department of Infectious Diseases, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China
| | - Xiaoyuan Chen
- Departments of Diagnostic Radiology, Surgery, Chemical and Biomolecular Engineering, and Biomedical Engineering, Yong Loo Lin School of Medicine and Faculty of Engineering, National University of Singapore, Singapore, 119074, Singapore; Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117599, Singapore; Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597, Singapore; Institute of Molecular and Cell Biology, Agency for Science, Technology, and Research (A*STAR), 61 Biopolis Drive, Proteos, Singapore, 138673, Singapore.
| | - Feng Xu
- Department of Infectious Diseases, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China.
| | - Min Zhou
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China; The National Key Laboratory of Biobased Transportation Fuel Technology, Zhejiang University, Hangzhou, 310027, China; Zhejiang University-University of Edinburgh Institute (ZJU-UoE Institute), Zhejiang University School of Medicine, Zhejiang University, Haining, 314400, China; Institute of Translational Medicine, Zhejiang University, Hangzhou, 310029, China.
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Maslova E, EisaianKhongi L, Rigole P, Coenye T, McCarthy RR. Carbon source competition within the wound microenvironment can significantly influence infection progression. NPJ Biofilms Microbiomes 2024; 10:52. [PMID: 38918415 PMCID: PMC11199515 DOI: 10.1038/s41522-024-00518-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 05/08/2024] [Indexed: 06/27/2024] Open
Abstract
It is becoming increasingly apparent that commensal skin bacteria have an important role in wound healing and infection progression. However, the precise mechanisms underpinning many of these probiotic interactions remain to be fully uncovered. In this work, we demonstrate that the common skin commensal Cutibacterium acnes can limit the pathogenicity of the prevalent wound pathogen Pseudomonas aeruginosa in vivo. We show that this impact on pathogenicity is independent of any effect on growth, but occurs through a significant downregulation of the Type Three Secretion System (T3SS), the primary toxin secretion system utilised by P. aeruginosa in eukaryotic infection. We also show a downregulation in glucose acquisition systems, a known regulator of the T3SS, suggesting that glucose availability in a wound can influence infection progression. C. acnes is well known as a glucose fermenting organism, and we demonstrate that topically supplementing a wound with glucose reverses the probiotic effects of C. acnes. This suggests that introducing carbon source competition within the wound microenvironment may be an effective way to prevent or limit wound infection.
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Affiliation(s)
- Evgenia Maslova
- Division of Biosciences, Department of Life Sciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UK
| | - Lara EisaianKhongi
- Division of Biosciences, Department of Life Sciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UK
| | - Petra Rigole
- Laboratory of Pharmaceutical Microbiology, Ghent University, 9000, Ghent, Belgium
| | - Tom Coenye
- Laboratory of Pharmaceutical Microbiology, Ghent University, 9000, Ghent, Belgium
| | - Ronan R McCarthy
- Division of Biosciences, Department of Life Sciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UK.
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4
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Ndugire W, Truong D, Hasitha Raviranga NG, Lao J, Ramström O, Yan M. Turning on the Antimicrobial Activity of Gold Nanoclusters Against Multidrug-Resistant Bacteria. Angew Chem Int Ed Engl 2023; 62:e202214086. [PMID: 36642692 PMCID: PMC10356176 DOI: 10.1002/anie.202214086] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 01/05/2023] [Accepted: 01/12/2023] [Indexed: 01/17/2023]
Abstract
In this work, we show that the addition of thiourea (TU) initiated broad-spectrum antimicrobial activity of otherwise inactive D-maltose-capped gold nanoclusters (AuNC-Mal). For example, AuNC-Mal/TU was effective against multidrug-resistant Pseudomonas aeruginosa with a minimum inhibitory concentration (MIC) of 1 μg mL-1 (2.5 μM [Au]) while having 30-60 times lower in vitro cytotoxicity against mammalian cells. The reaction of AuNC-Mal and TU generated the antimicrobial species of [Au(TU)2 ]+ and smaller AuNCs. TU increased the accumulation of Au in bacteria and helped maintain the oxidation state as AuI (vs. AuIII ). The modes of action included the inhibition of thioredoxin reductase, interference with the CuI regulation and depletion of ATP. Moreover, the antimicrobial activity did not change in the presence of colistin or carbonyl cyanide 3-chlorophenylhydrazone, suggesting that AuNC-Mal/TU was indifferent to the outer membrane barrier and to bacterial efflux pumps.
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Affiliation(s)
- William Ndugire
- Department of Chemistry, University of Massachusetts Lowell, One University Ave., Lowell, MA-01854, USA
| | - Dang Truong
- Department of Chemistry, University of Massachusetts Lowell, One University Ave., Lowell, MA-01854, USA
| | - N G Hasitha Raviranga
- Department of Chemistry, University of Massachusetts Lowell, One University Ave., Lowell, MA-01854, USA
| | - Jingzhe Lao
- Department of Chemistry, University of Massachusetts Lowell, One University Ave., Lowell, MA-01854, USA
| | - Olof Ramström
- Department of Chemistry, University of Massachusetts Lowell, One University Ave., Lowell, MA-01854, USA
- Department of Chemistry and Biomedical Sciences, Linnaeus University, 39182, Kalmar, Sweden
| | - Mingdi Yan
- Department of Chemistry, University of Massachusetts Lowell, One University Ave., Lowell, MA-01854, USA
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5
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Falchi FA, Borlotti G, Ferretti F, Pellegrino G, Raneri M, Schiavoni M, Caselli A, Briani F. Sanguinarine Inhibits the 2-Ketogluconate Pathway of Glucose Utilization in Pseudomonas aeruginosa. Front Microbiol 2021; 12:744458. [PMID: 34566945 PMCID: PMC8461315 DOI: 10.3389/fmicb.2021.744458] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 08/12/2021] [Indexed: 01/13/2023] Open
Abstract
Interfering with the ability of pathogenic bacteria to import glucose may represent a new promising antibacterial strategy, especially for the treatment of infections occurring in diabetic and other hyperglycemic patients. Such patients are particularly susceptible to infections caused by a variety of bacteria, among which opportunistic pathogens like Pseudomonas aeruginosa. In P. aeruginosa, glucose can be directly imported into the cytoplasm or after its periplasmic oxidation into gluconate and 2-ketogluconate (2-KG). We recently demonstrated that a P. aeruginosa mutant lacking the 2-KG transporter KguT is less virulent than its kguT+ parental strain in an insect infection model, pointing to 2-KG branch of glucose utilization as a possible target for anti-Pseudomonas drugs. In this work, we devised an experimental protocol to find specific inhibitors of the 2-KG pathway of P. aeruginosa glucose utilization and applied it to the screening of the Prestwick Chemical Library. By exploiting mutants lacking genes involved in the transport of glucose derivatives in the primary screening and in the secondary assays, we could identify sanguinarine as an inhibitor of 2-KG utilization. We also demonstrated that sanguinarine does not prevent 2-KG formation by gluconate oxidation or its transport, suggesting that either KguD or KguK is the target of sanguinarine in P. Aeruginosa.
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Affiliation(s)
- Federica A Falchi
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milan, Italy
| | - Giorgia Borlotti
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milan, Italy
| | | | | | - Matteo Raneri
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milan, Italy
| | - Marco Schiavoni
- Dipartimento di Chimica, Università degli Studi di Milano, Milan, Italy
| | | | - Federica Briani
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milan, Italy
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Transcriptomic Analysis of Pseudomonas aeruginosa Response to Pine Honey via RNA Sequencing Indicates Multiple Mechanisms of Antibacterial Activity. Foods 2021; 10:foods10050936. [PMID: 33923242 PMCID: PMC8145095 DOI: 10.3390/foods10050936] [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: 04/05/2021] [Revised: 04/19/2021] [Accepted: 04/22/2021] [Indexed: 12/12/2022] Open
Abstract
Pine honey is a unique type of honeydew honey produced exclusively in Eastern Mediterranean countries like Greece and Turkey. Although the antioxidant and anti-inflammatory properties of pine honey are well documented, few studies have investigated so far its antibacterial activity. This study investigates the antibacterial effects of pine honey against P. aeruginosa PA14 at the molecular level using a global transcriptome approach via RNA-sequencing. Pine honey treatment was applied at sub-inhibitory concentration and short exposure time (0.5× of minimum inhibitory concentration –MIC- for 45 min). Pine honey induced the differential expression (>two-fold change and p ≤ 0.05) of 463 genes, with 274 of them being down-regulated and 189 being up-regulated. Gene ontology (GO) analysis revealed that pine honey affected a wide range of biological processes (BP). The most affected down-regulated BP GO terms were oxidation-reduction process, transmembrane transport, proteolysis, signal transduction, biosynthetic process, phenazine biosynthetic process, bacterial chemotaxis, and antibiotic biosynthetic process. The up-regulated BP terms, affected by pine honey treatment, were those related to the regulation of DNA-templated transcription, siderophore transport, and phosphorylation. Pathway analysis revealed that pine honey treatment significantly affected two-component regulatory systems, ABC transporter systems, quorum sensing, bacterial chemotaxis, biofilm formation and SOS response. These data collectively indicate that multiple mechanisms of action are implicated in antibacterial activity exerted by pine honey against P. aeruginosa.
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7
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Raneri M, Pinatel E, Peano C, Rampioni G, Leoni L, Bianconi I, Jousson O, Dalmasio C, Ferrante P, Briani F. Pseudomonas aeruginosa mutants defective in glucose uptake have pleiotropic phenotype and altered virulence in non-mammal infection models. Sci Rep 2018; 8:16912. [PMID: 30442901 PMCID: PMC6237876 DOI: 10.1038/s41598-018-35087-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 10/30/2018] [Indexed: 01/09/2023] Open
Abstract
Pseudomonas spp. are endowed with a complex pathway for glucose uptake that relies on multiple transporters. In this work we report the construction and characterization of Pseudomonas aeruginosa single and multiple mutants with unmarked deletions of genes encoding outer membrane (OM) and inner membrane (IM) proteins involved in glucose uptake. We found that a triple ΔgltKGF ΔgntP ΔkguT mutant lacking all known IM transporters (named GUN for Glucose Uptake Null) is unable to grow on glucose as unique carbon source. More than 500 genes controlling both metabolic functions and virulence traits show differential expression in GUN relative to the parental strain. Consistent with transcriptomic data, the GUN mutant displays a pleiotropic phenotype. Notably, the genome-wide transcriptional profile and most phenotypic traits differ between the GUN mutant and the wild type strain irrespective of the presence of glucose, suggesting that the investigated genes may have additional roles besides glucose transport. Finally, mutants carrying single or multiple deletions in the glucose uptake genes showed attenuated virulence relative to the wild type strain in Galleria mellonella, but not in Caenorhabditis elegans infection model, supporting the notion that metabolic functions may deeply impact P. aeruginosa adaptation to specific environments found inside the host.
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Affiliation(s)
- Matteo Raneri
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy
| | - Eva Pinatel
- Istituto di Tecnologie Biomediche-CNR, Segrate, Italy
| | - Clelia Peano
- Istituto di Tecnologie Biomediche-CNR, Segrate, Italy
- Istituto Clinico Humanitas-CNR, Rozzano, Italy
| | - Giordano Rampioni
- Dipartimento di Scienze, Università degli Studi Roma Tre, Roma, Italy
| | - Livia Leoni
- Dipartimento di Scienze, Università degli Studi Roma Tre, Roma, Italy
| | - Irene Bianconi
- Centre for Integrative Biology, Università degli Studi di Trento, Trento, Italy
| | - Olivier Jousson
- Centre for Integrative Biology, Università degli Studi di Trento, Trento, Italy
| | - Chiara Dalmasio
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy
| | - Palma Ferrante
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy
| | - Federica Briani
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milano, Italy.
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8
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Pandey S, Modak A, Phale PS, Bhaumik P. High Resolution Structures of Periplasmic Glucose-binding Protein of Pseudomonas putida CSV86 Reveal Structural Basis of Its Substrate Specificity. J Biol Chem 2016; 291:7844-57. [PMID: 26861882 DOI: 10.1074/jbc.m115.697268] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Indexed: 01/31/2023] Open
Abstract
Periplasmic substrate-binding proteins (SBPs) bind to the specific ligand with high affinity and mediate their transport into the cytoplasm via the cognate inner membrane ATP-binding cassette proteins. Because of low sequence identities, understanding the structural basis of substrate recognition by SBPs has remained very challenging. There are several structures available for the ligand-bound sugar SBPs, but very few unliganded structures are reported. No structural data are available for sugar SBPs fromPseudomonassp. to date. This study reports the first high resolution crystal structures of periplasmic glucose-binding protein fromPseudomonas putidaCSV86 (ppGBP) in unliganded form (2.5 Å) and complexed with glucose (1.25 Å) and galactose (1.8 Å). Asymmetric domain closure of ppGBP was observed upon substrate binding. The ppGBP was found to have an affinity of ∼ 0.3 μmfor glucose. The structural analysis showed that the sugars are bound to the protein mainly by hydrogen bonds, and the loss of two strong hydrogen bonds between ppGBP and galactose compared with glucose may be responsible for lowering its affinity toward galactose. The higher stability of ppGBP-glucose complex was also indicated by an 8 °C increase in the melting temperature compared with unliganded form and ppGBP-galactose complex. ppGBP binds to monosaccharide, but the structural features revealed it to have an oligosaccharide-binding protein fold, indicating that during evolution the sugar binding pocket may have undergone structural modulation to accommodate monosaccharide only.
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Affiliation(s)
- Suman Pandey
- From the Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Arnab Modak
- From the Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Prashant S Phale
- From the Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Prasenjit Bhaumik
- From the Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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Shetye GS, Singh N, Jia C, Nguyen CDK, Wang G, Luk YY. Specific Maltose Derivatives Modulate the Swarming Motility of Nonswarming Mutant and Inhibit Bacterial Adhesion and Biofilm Formation byPseudomonas aeruginosa. Chembiochem 2014; 15:1514-23. [DOI: 10.1002/cbic.201402093] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Indexed: 11/10/2022]
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10
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Shrivastava R, Basu B, Godbole A, Mathew MK, Apte SK, Phale PS. Repression of the glucose-inducible outer-membrane protein OprB during utilization of aromatic compounds and organic acids in Pseudomonas putida CSV86. MICROBIOLOGY-SGM 2011; 157:1531-1540. [PMID: 21330430 DOI: 10.1099/mic.0.047191-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Pseudomonas putida CSV86 shows preferential utilization of aromatic compounds over glucose. Protein analysis and [¹⁴C]glucose-binding studies of the outer membrane fraction of cells grown on different carbon sources revealed a 40 kDa protein that was transcriptionally induced by glucose and repressed by aromatics and succinate. Based on 2D gel electrophoresis and liquid chromatography-tandem mass spectrometry analysis, the 40 kDa protein closely resembled the porin B of P. putida KT2440 and carbohydrate-selective porin OprB of various Pseudomonas strains. The purified native protein (i) was estimated to be a homotrimer of 125 kDa with a subunit molecular mass of 40 kDa, (ii) displayed heat modifiability of electrophoretic mobility, (iii) showed channel conductance of 166 pS in 1 M KCl, (iv) permeated various sugars (mono-, di- and tri-saccharides), organic acids, amino acids and aromatic compounds, and (v) harboured a glucose-specific and saturable binding site with a dissociation constant of 1.3 µM. These results identify the glucose-inducible outer-membrane protein of P. putida CSV86 as a carbohydrate-selective protein OprB. Besides modulation of intracellular glucose-metabolizing enzymes and specific glucose-binding periplasmic space protein, the repression of OprB by aromatics and organic acids, even in the presence of glucose, also contributes significantly to the strain's ability to utilize aromatics and organic acids over glucose.
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Affiliation(s)
- Rahul Shrivastava
- Department of Biosciences and Bioengineering, Indian Institute of Technology-Bombay, Powai, Mumbai 400 076, India
| | - Bhakti Basu
- Molecular Biology Division, Bhabha Atomic Research Center, Trombay, Mumbai 400 085, India
| | - Ashwini Godbole
- National Center for Biological Sciences, Bangalore 560 065, India
| | - M K Mathew
- National Center for Biological Sciences, Bangalore 560 065, India
| | - Shree K Apte
- Molecular Biology Division, Bhabha Atomic Research Center, Trombay, Mumbai 400 085, India
| | - Prashant S Phale
- Department of Biosciences and Bioengineering, Indian Institute of Technology-Bombay, Powai, Mumbai 400 076, India
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Tremblay J, Déziel E. Gene expression in Pseudomonas aeruginosa swarming motility. BMC Genomics 2010; 11:587. [PMID: 20961425 PMCID: PMC3091734 DOI: 10.1186/1471-2164-11-587] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Accepted: 10/20/2010] [Indexed: 12/25/2022] Open
Abstract
Background The bacterium Pseudomonas aeruginosa is capable of three types of motilities: swimming, twitching and swarming. The latter is characterized by a fast and coordinated group movement over a semi-solid surface resulting from intercellular interactions and morphological differentiation. A striking feature of swarming motility is the complex fractal-like patterns displayed by migrating bacteria while they move away from their inoculation point. This type of group behaviour is still poorly understood and its characterization provides important information on bacterial structured communities such as biofilms. Using GeneChip® Affymetrix microarrays, we obtained the transcriptomic profiles of both bacterial populations located at the tip of migrating tendrils and swarm center of swarming colonies and compared these profiles to that of a bacterial control population grown on the same media but solidified to not allow swarming motility. Results Microarray raw data were corrected for background noise with the RMA algorithm and quantile normalized. Differentially expressed genes between the three conditions were selected using a threshold of 1.5 log2-fold, which gave a total of 378 selected genes (6.3% of the predicted open reading frames of strain PA14). Major shifts in gene expression patterns are observed in each growth conditions, highlighting the presence of distinct bacterial subpopulations within a swarming colony (tendril tips vs. swarm center). Unexpectedly, microarrays expression data reveal that a minority of genes are up-regulated in tendril tip populations. Among them, we found energy metabolism, ribosomal protein and transport of small molecules related genes. On the other hand, many well-known virulence factors genes were globally repressed in tendril tip cells. Swarm center cells are distinct and appear to be under oxidative and copper stress responses. Conclusions Results reported in this study show that, as opposed to swarm center cells, tendril tip populations of a swarming colony displays general down-regulation of genes associated with virulence and up-regulation of genes involved in energy metabolism. These results allow us to propose a model where tendril tip cells function as «scouts» whose main purpose is to rapidly spread on uncolonized surfaces while swarm center population are in a state allowing a permanent settlement of the colonized area (biofilm-like).
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Affiliation(s)
- Julien Tremblay
- INRS-Institut Armand-Frappier, Laval (Québec), H7V 1B7, Canada
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12
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Basu A, Shrivastava R, Basu B, Apte SK, Phale PS. Modulation of glucose transport causes preferential utilization of aromatic compounds in Pseudomonas putida CSV86. J Bacteriol 2007; 189:7556-62. [PMID: 17827293 PMCID: PMC2168731 DOI: 10.1128/jb.01235-07] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas putida CSV86 utilizes aromatic compounds in preference to glucose and coutilizes aromatics and organic acids. Protein analysis of cells grown on different carbon sources, either alone or in combination, revealed that a 43-kDa periplasmic-space protein was induced by glucose and repressed by aromatics and succinate. Two-dimensional gel electrophoresis and liquid chromatography-tandem mass spectrometry analysis identified this protein as closely resembling the sugar ABC transporter of Pseudomonas putida KT2440. A partially purified 43-kDa protein showed glucose binding activity and was specific for glucose. The results demonstrate that the aromatic- and organic acid-mediated repression of a periplasmic-space glucose binding protein and consequent inhibition of glucose transport are responsible for this strain's ability to utilize aromatics and organic acids in preference to glucose.
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Affiliation(s)
- Aditya Basu
- Biotechnology Group, School of Biosciences and Bioengineering, Indian Institute of Technology-Bombay, Powai, Mumbai 400 076, India
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13
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Baker EH, Wood DM, Brennan AL, Clark N, Baines DL, Philips BJ. Hyperglycaemia and pulmonary infection. Proc Nutr Soc 2007; 65:227-35. [PMID: 16923307 DOI: 10.1079/pns2006499] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Pathophysiological stress from acute illness causes metabolic disturbance, including altered hepatic glucose metabolism, increased peripheral insulin resistance and hyperglycaemia. Acute hyperglycaemia is associated with increased morbidity and mortality in patients in intensive care units and patients with acute respiratory disease. The present review will consider mechanisms underlying this association. In normal lungs the glucose concentration of airway secretions is approximately 10-fold lower than that of plasma. Low airway glucose concentrations are maintained against a concentration gradient by active glucose transport. Airway glucose concentrations become elevated if normal homeostasis is disrupted by a rise in blood glucose concentrations or inflammation of the airway epithelium. Elevated airway glucose concentrations are associated with and precede increased isolation of respiratory pathogens, particularly methicillin-resistant Staphylococcus aureus, from bronchial aspirates of patients intubated on intensive care. Markers of elevated airway glucose are associated with similar patterns of respiratory infection in patients admitted with acute exacerbations of chronic obstructive pulmonary disease. Glucose at airway concentrations stimulates the growth of respiratory pathogens, over and above the effect of other nutrients. Elevated airway glucose concentrations may also worsen respiratory disease by promoting local inflammation. Hyperglycaemia may thus promote pulmonary infection, at least in part, by an effect on airway glucose concentrations. Therapeutic options, including systemic control of blood glucose and local manipulation of airway glucose homeostasis, will be considered.
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Affiliation(s)
- Emma H Baker
- Glucose and Pulmonary Infection Group, Cardiac and Vascular Sciences (Respiratory), St George's, University of London, Cranmer Terrace, London SW17 0RE, UK.
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Cuneo MJ, Changela A, Warren JJ, Beese LS, Hellinga HW. The crystal structure of a thermophilic glucose binding protein reveals adaptations that interconvert mono and di-saccharide binding sites. J Mol Biol 2006; 362:259-70. [PMID: 16904687 DOI: 10.1016/j.jmb.2006.06.084] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2006] [Revised: 06/20/2006] [Accepted: 06/27/2006] [Indexed: 11/19/2022]
Abstract
Periplasmic binding proteins (PBPs) comprise a protein superfamily that is involved in prokaryotic solute transport and chemotaxis. These proteins have been used to engineer reagentless biosensors to detect natural or non-natural ligands. There is considerable interest in obtaining very stable members of this superfamily from thermophilic bacteria to use as robust engineerable parts in biosensor development. Analysis of the recently determined genome sequence of Thermus thermophilus revealed the presence of more than 30 putative PBPs in this thermophile. One of these is annotated as a glucose binding protein (GBP) based on its genetic linkage to genes that are homologous to an ATP-binding cassette glucose transport system, although the PBP sequence is homologous to periplasmic maltose binding proteins (MBPs). Here we present the cloning, over-expression, characterization of cognate ligands, and determination of the X-ray crystal structure of this gene product. We find that it is a very stable (apo-protein Tm value is 100(+/- 2) degrees C; complexes 106(+/- 3) degrees C and 111(+/- 1) degrees C for glucose and galactose, respectively) glucose (Kd value is 0.08(+/- 0.03) microM) and galactose (Kd value is 0.94(+/- 0.04) microM) binding protein. Determination of the X-ray crystal structure revealed that this T. thermophilus glucose binding protein (ttGBP) is structurally homologous to MBPs rather than other GBPs. The di or tri-saccharide ligands in MBPs are accommodated in long relatively shallow grooves. In the ttGBP binding site, this groove is partially filled by two loops and an alpha-helix, which create a buried binding site that allows binding of only monosaccharides. Comparison of ttGBP and MBP provides a clear example of structural adaptations by which the size of ligand binding sites can be controlled in the PBP super family.
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Affiliation(s)
- Matthew J Cuneo
- The Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
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15
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Location, formation and biosynthetic regulation of cellulases in the gliding bacteria Cytophaga hutchinsonii. Int J Mol Sci 2006. [DOI: 10.3390/i7010001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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16
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Llamas MA, Rodríguez-Herva JJ, Hancock REW, Bitter W, Tommassen J, Ramos JL. Role of Pseudomonas putida tol-oprL gene products in uptake of solutes through the cytoplasmic membrane. J Bacteriol 2003; 185:4707-16. [PMID: 12896989 PMCID: PMC166457 DOI: 10.1128/jb.185.16.4707-4716.2003] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Proteins of the Tol-Pal (Tol-OprL) system play a key role in the maintenance of outer membrane integrity and cell morphology in gram-negative bacteria. Here we describe an additional role for this system in the transport of various carbon sources across the cytoplasmic membrane. Growth of Pseudomonas putida tol-oprL mutant strains in minimal medium with glycerol, fructose, or arginine was impaired, and the growth rate with succinate, proline, or sucrose as the carbon source was lower than the growth rate of the parental strain. Assays with radiolabeled substrates revealed that the rates of uptake of these compounds by mutant cells were lower than the rates of uptake by the wild-type strain. The pattern and amount of outer membrane protein in the P. putida tol-oprL mutants were not changed, suggesting that the transport defect was not in the outer membrane. Consistently, the uptake of radiolabeled glucose and glycerol in spheroplasts was defective in the P. putida tol-oprL mutant strains, suggesting that there was a defect at the cytoplasmic membrane level. Generation of a proton motive force appeared to be unaffected in these mutants. To rule out the possibility that the uptake defect was due to a lack of specific transporter proteins, the PutP symporter was overproduced, but this overproduction did not enhance proline uptake in the tol-oprL mutants. These results suggest that the Tol-OprL system is necessary for appropriate functioning of certain uptake systems at the level of the cytoplasmic membrane.
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Affiliation(s)
- María A Llamas
- Department of Biochemistry and Molecular and Cellular Biology of Plants, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain
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17
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DelVecchio VG, Kapatral V, Redkar RJ, Patra G, Mujer C, Los T, Ivanova N, Anderson I, Bhattacharyya A, Lykidis A, Reznik G, Jablonski L, Larsen N, D'Souza M, Bernal A, Mazur M, Goltsman E, Selkov E, Elzer PH, Hagius S, O'Callaghan D, Letesson JJ, Haselkorn R, Kyrpides N, Overbeek R. The genome sequence of the facultative intracellular pathogen Brucella melitensis. Proc Natl Acad Sci U S A 2002; 99:443-8. [PMID: 11756688 PMCID: PMC117579 DOI: 10.1073/pnas.221575398] [Citation(s) in RCA: 396] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Brucella melitensis is a facultative intracellular bacterial pathogen that causes abortion in goats and sheep and Malta fever in humans. The genome of B. melitensis strain 16M was sequenced and found to contain 3,294,935 bp distributed over two circular chromosomes of 2,117,144 bp and 1,177,787 bp encoding 3,197 ORFs. By using the bioinformatics suite ERGO, 2,487 (78%) ORFs were assigned functions. The origins of replication of the two chromosomes are similar to those of other alpha-proteobacteria. Housekeeping genes, including those involved in DNA replication, transcription, translation, core metabolism, and cell wall biosynthesis, are distributed on both chromosomes. Type I, II, and III secretion systems are absent, but genes encoding sec-dependent, sec-independent, and flagella-specific type III, type IV, and type V secretion systems as well as adhesins, invasins, and hemolysins were identified. Several features of the B. melitensis genome are similar to those of the symbiotic Sinorhizobium meliloti.
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Affiliation(s)
- Vito G DelVecchio
- Institute of Molecular Biology and Medicine, University of Scranton, Scranton, PA 18510, USA.
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