1
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Khan F, Jeong MC, Park SK, Kim SK, Kim YM. Contribution of chitooligosaccharides to biofilm formation, antibiotics resistance and disinfectants tolerance of Listeria monocytogenes. Microb Pathog 2019; 136:103673. [PMID: 31437576 DOI: 10.1016/j.micpath.2019.103673] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 08/16/2019] [Accepted: 08/19/2019] [Indexed: 01/31/2023]
Abstract
Listeria monocytogenes is a food-borne pathogen present in various environmental reservoirs. It exhibits resistance and tolerance to antibiotics and sanitizing agents used in several food processing industries. It has been reported that L. monocytogenes chitinase can catalyze hydrolysis of chitin polymeric carbohydrate present in the environment and act as a virulence factor that support its survival in mammalian host cells. By taking advantage of chitinase, L. monocytogenes has both saprophytic and pathogenic lifestyles in the soil and the living host, respectively. The objective of the present study was to determine the involvement of chitin degradation products such as chitooligosaccharides (COS) in biofilm formation of L. monocytogenes. Results showed that different concentrations of COS with various molecular weight enhanced biofilm formation of L. monocytogenes. Such enhancement in biofilm formation contributed to the development of antibiotics resistance and disinfectants tolerance of cells present in the biofilm. The present article also described diverse roles of chitin, chitinase, and degradation of chitin and chitin-like substrates in saprophytic and pathogenic lifestyles of L. monocytogenes. This study offers a new direction for further exploration of the mechanisms of pathogenesis caused by L. monocytogenes.
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Affiliation(s)
- Fazlurrahman Khan
- Marine-Integrated Bionics Research Center, Pukyong National University, Busan, 48513, South Korea
| | - Min-Chul Jeong
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, South Korea
| | - Seul-Ki Park
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, South Korea
| | - Shin-Kwon Kim
- Aquaculture Research Division, National Institute of Fisheries Science, Busan, 46083, South Korea
| | - Young-Mog Kim
- Marine-Integrated Bionics Research Center, Pukyong National University, Busan, 48513, South Korea; Department of Food Science and Technology, Pukyong National University, Busan, 48513, South Korea.
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2
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Shen Y, Boulos S, Sumrall E, Gerber B, Julian-Rodero A, Eugster MR, Fieseler L, Nyström L, Ebert MO, Loessner MJ. Structural and functional diversity in Listeria cell wall teichoic acids. J Biol Chem 2017; 292:17832-17844. [PMID: 28912268 DOI: 10.1074/jbc.m117.813964] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Indexed: 11/06/2022] Open
Abstract
Wall teichoic acids (WTAs) are the most abundant glycopolymers found on the cell wall of many Gram-positive bacteria, whose diverse surface structures play key roles in multiple biological processes. Despite recent technological advances in glycan analysis, structural elucidation of WTAs remains challenging due to their complex nature. Here, we employed a combination of ultra-performance liquid chromatography-coupled electrospray ionization tandem-MS/MS and NMR to determine the structural complexity of WTAs from Listeria species. We unveiled more than 10 different types of WTA polymers that vary in their linkage and repeating units. Disparity in GlcNAc to ribitol connectivity, as well as variable O-acetylation and glycosylation of GlcNAc contribute to the structural diversity of WTAs. Notably, SPR analysis indicated that constitution of WTA determines the recognition by bacteriophage endolysins. Collectively, these findings provide detailed insight into Listeria cell wall-associated carbohydrates, and will guide further studies on the structure-function relationship of WTAs.
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Affiliation(s)
- Yang Shen
- From the Laboratory of Food Microbiology, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, CH-8092 Zurich,
| | - Samy Boulos
- the Laboratory of Food Biochemistry, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, CH-8092 Zurich
| | - Eric Sumrall
- From the Laboratory of Food Microbiology, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, CH-8092 Zurich
| | - Benjamin Gerber
- From the Laboratory of Food Microbiology, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, CH-8092 Zurich
| | - Alicia Julian-Rodero
- From the Laboratory of Food Microbiology, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, CH-8092 Zurich
| | - Marcel R Eugster
- From the Laboratory of Food Microbiology, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, CH-8092 Zurich
| | - Lars Fieseler
- the ZHAW School of Life Sciences and Facility Management, Einsiedlerstrasse 31, CH-8820 Wädenswil, and
| | - Laura Nyström
- the Laboratory of Food Biochemistry, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, CH-8092 Zurich
| | - Marc-Olivier Ebert
- the Laboratory of Organic Chemistry, ETH Zurich, Vladmimir-Prelog-Weg 3, CH-8093 Zurich, Switzerland
| | - Martin J Loessner
- From the Laboratory of Food Microbiology, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, CH-8092 Zurich
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3
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Suppressor Mutations Linking gpsB with the First Committed Step of Peptidoglycan Biosynthesis in Listeria monocytogenes. J Bacteriol 2016; 199:JB.00393-16. [PMID: 27795316 DOI: 10.1128/jb.00393-16] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 10/16/2016] [Indexed: 02/07/2023] Open
Abstract
The cell division protein GpsB is a regulator of the penicillin binding protein A1 (PBP A1) in the Gram-positive human pathogen Listeria monocytogenes Penicillin binding proteins mediate the last two steps of peptidoglycan biosynthesis as they polymerize and cross-link peptidoglycan strands, the main components of the bacterial cell wall. It is not known what other processes are controlled by GpsB. L. monocytogenes gpsB mutants are unable to grow at 42°C, but we observed that spontaneous suppressors correcting this defect arise on agar plates with high frequency. We here describe a first set of gpsB suppressors that mapped to the clpC and murZ genes. While ClpC is the ATPase component of the Clp protease, MurZ is a paralogue of the listerial UDP-N-acetylglucosamine (UDP-GlcNAc) 1-carboxyvinyltransferase MurA. Both enzymes catalyze the enolpyruvyl transfer from phosphoenolpyruvate to UDP-GlcNAc, representing the first committed step of peptidoglycan biosynthesis. We confirmed that clean deletion of the clpC or murZ gene suppressed the ΔgpsB phenotype. It turned out that the absence of either gene leads to accumulation of MurA, and we show that artificial overexpression of MurA alone was sufficient for suppression. Inactivation of other UDP-GlcNAc-consuming pathways also suppressed the heat-sensitive growth of the ΔgpsB mutant, suggesting that an increased influx of precursor molecules into peptidoglycan biosynthesis can compensate for the lack of GpsB. Our results support a model according to which PBP A1 becomes misregulated and thus toxic in the absence of GpsB due to unproductive consumption of cell wall precursor molecules. IMPORTANCE The late cell division protein GpsB is important for cell wall biosynthesis in Gram-positive bacteria. GpsB of the human pathogen L. monocytogenes interacts with one of the key enzymes of this pathway, penicillin binding protein A1 (PBP A1), and influences its activity. PBP A1 catalyzes the last two steps of cell wall biosynthesis, but it is unknown how GpsB controls PBP A1. We observed that a L. monocytogenes gpsB mutant forms spontaneous suppressors and have mapped their mutations to genes mediating and influencing the first step of cell wall biosynthesis, likely stimulating the influx of metabolites into this pathway. We assume that GpsB is important to ensure productive incorporation of cell wall precursors into the peptidoglycan sacculus by PBP A1.
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4
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Brauge T, Sadovskaya I, Faille C, Benezech T, Maes E, Guerardel Y, Midelet-Bourdin G. Teichoic acid is the major polysaccharide present in theListeria monocytogenesbiofilm matrix. FEMS Microbiol Lett 2015; 363:fnv229. [DOI: 10.1093/femsle/fnv229] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/25/2015] [Indexed: 12/30/2022] Open
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5
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Zhang L, Muthana MM, Yu H, McArthur JB, Qu J, Chen X. Characterizing non-hydrolyzing Neisseria meningitidis serogroup A UDP-N-acetylglucosamine (UDP-GlcNAc) 2-epimerase using UDP-N-acetylmannosamine (UDP-ManNAc) and derivatives. Carbohydr Res 2015; 419:18-28. [PMID: 26598987 DOI: 10.1016/j.carres.2015.10.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2015] [Revised: 10/26/2015] [Accepted: 10/29/2015] [Indexed: 11/28/2022]
Abstract
Neisseria meningitidis serogroup A non-hydrolyzing uridine 5'-diphosphate-N-acetylglucosamine (UDP-GlcNAc) 2-epimerase (NmSacA) catalyzes the interconversion between UDP-GlcNAc and uridine 5'-diphosphate-N-acetylmannosamine (UDP-ManNAc). It is a key enzyme involved in the biosynthesis of the capsular polysaccharide [-6ManNAcα1-phosphate-]n of N. meningitidis serogroup A, one of the six serogroups (A, B, C, W-135, X, and Y) that account for most cases of N. meningitidis-caused bacterial septicemia and meningitis. N. meningitidis serogroup A is responsible for large epidemics in the developing world, especially in Africa. Here we report that UDP-ManNAc could be used as a substrate for C-terminal His6-tagged recombinant NmSacA (NmSacA-His6) in the absence of UDP-GlcNAc. NmSacA-His6 was activated by UDP-GlcNAc and inhibited by 2-acetamidoglucal and UDP. Substrate specificity study showed that NmSacA-His6 could tolerate several chemoenzymatically synthesized UDP-ManNAc derivatives as substrates although its activity was much lower than non-modified UDP-ManNAc. Homology modeling and molecular docking revealed likely structural determinants of NmSacA substrate specificity. This is the first detailed study of N. meningitidis serogroup A UDP-GlcNAc 2-epimerase.
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Affiliation(s)
- Lei Zhang
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Musleh M Muthana
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Hai Yu
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
| | - John B McArthur
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Jingyao Qu
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Xi Chen
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA.
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6
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Denes T, den Bakker HC, Tokman JI, Guldimann C, Wiedmann M. Selection and Characterization of Phage-Resistant Mutant Strains of Listeria monocytogenes Reveal Host Genes Linked to Phage Adsorption. Appl Environ Microbiol 2015; 81:4295-305. [PMID: 25888172 PMCID: PMC4475870 DOI: 10.1128/aem.00087-15] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 04/12/2015] [Indexed: 02/06/2023] Open
Abstract
Listeria-infecting phages are readily isolated from Listeria-containing environments, yet little is known about the selective forces they exert on their host. Here, we identified that two virulent phages, LP-048 and LP-125, adsorb to the surface of Listeria monocytogenes strain 10403S through different mechanisms. We isolated and sequenced, using whole-genome sequencing, 69 spontaneous mutant strains of 10403S that were resistant to either one or both phages. Mutations from 56 phage-resistant mutant strains with only a single mutation mapped to 10 genes representing five loci on the 10403S chromosome. An additional 12 mutant strains showed two mutations, and one mutant strain showed three mutations. Two of the loci, containing seven of the genes, accumulated the majority (n = 64) of the mutations. A representative mutant strain for each of the 10 genes was shown to resist phage infection through mechanisms of adsorption inhibition. Complementation of mutant strains with the associated wild-type allele was able to rescue phage susceptibility for 6 out of the 10 representative mutant strains. Wheat germ agglutinin, which specifically binds to N-acetylglucosamine, bound to 10403S and mutant strains resistant to LP-048 but did not bind to mutant strains resistant to only LP-125. We conclude that mutant strains resistant to only LP-125 lack terminal N-acetylglucosamine in their wall teichoic acid (WTA), whereas mutant strains resistant to both phages have disruptive mutations in their rhamnose biosynthesis operon but still possess N-acetylglucosamine in their WTA.
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Affiliation(s)
- Thomas Denes
- Department of Food Science, Cornell University, Ithaca, New York, USA
| | - Henk C den Bakker
- Department of Food Science, Cornell University, Ithaca, New York, USA
| | - Jeffrey I Tokman
- Department of Food Science, Cornell University, Ithaca, New York, USA
| | - Claudia Guldimann
- Department of Food Science, Cornell University, Ithaca, New York, USA
| | - Martin Wiedmann
- Department of Food Science, Cornell University, Ithaca, New York, USA
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7
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Casey A, Fox EM, Schmitz-Esser S, Coffey A, McAuliffe O, Jordan K. Transcriptome analysis of Listeria monocytogenes exposed to biocide stress reveals a multi-system response involving cell wall synthesis, sugar uptake, and motility. Front Microbiol 2014; 5:68. [PMID: 24616718 PMCID: PMC3937556 DOI: 10.3389/fmicb.2014.00068] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 02/07/2014] [Indexed: 12/02/2022] Open
Abstract
Listeria monocytogenes is a virulent food-borne pathogen most often associated with the consumption of “ready-to-eat” foods. The organism is a common contaminant of food processing plants where it may persist for extended periods of time. A commonly used approach for the control of Listeria monocytogenes in the processing environment is the application of biocides such as quaternary ammonium compounds. In this study, the transcriptomic response of a persistent strain of L. monocytogenes (strain 6179) on exposure to a sub-lethal concentration of the quaternary ammonium compound benzethonium chloride (BZT) was assessed. Using RNA-Seq, gene expression levels were quantified by sequencing the transcriptome of L. monocytogenes 6179 in the presence (4 ppm) and absence of BZT, and mapping each data set to the sequenced genome of strain 6179. Hundreds of differentially expressed genes were identified, and subsequent analysis suggested that many biological processes such as peptidoglycan biosynthesis, bacterial chemotaxis and motility, and carbohydrate uptake, were involved in the response of L. monocyotogenes to the presence of BZT. The information generated in this study further contributes to our understanding of the response of bacteria to environmental stress. In addition, this study demonstrates the importance of using the bacterium's own genome as a reference when analysing RNA-Seq data.
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Affiliation(s)
- Aidan Casey
- Teagasc Food Research Centre Fermoy, Ireland
| | - Edward M Fox
- CSIRO Animal Food and Health Sciences Werribee, VIC, Australia
| | - Stephan Schmitz-Esser
- Department of Farm Animals and Veterinary Public Health, Institute of Milk Hygiene, University of Veterinary Medicine Vienna, Austria
| | - Aidan Coffey
- Department of Biological Sciences, Cork Institute of Technology Cork, Ireland
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8
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Eugster MR, Loessner MJ. The Listeria cell wall and associated carbohydrate polymers. Methods Mol Biol 2014; 1157:129-40. [PMID: 24792554 DOI: 10.1007/978-1-4939-0703-8_11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Understanding molecular interactions of bacteria with their environment requires the purification and characterization of cell wall components. Here, we describe detailed experimental methods for the extraction, purification, and analysis of wall teichoic acids (WTA), which assume important roles as major constituents of Gram-positive cell walls, such as mediating interaction with cell wall-associated proteins, eukaryotic host cells, and bacteriophages. Specifically, we present a procedure for compositional WTA characterization to study large diversity of carbohydrate substitution on Listeria monocytogenes WTA. This protocol may also be used and adapted to analyze WTA from other bacteria.
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Affiliation(s)
- Marcel R Eugster
- Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, CH-8092, Zurich, Switzerland
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9
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Krawczyk-Balska A, Lipiak M. Critical role of a ferritin-like protein in the control of Listeria monocytogenes cell envelope structure and stability under β-lactam pressure. PLoS One 2013; 8:e77808. [PMID: 24204978 PMCID: PMC3812014 DOI: 10.1371/journal.pone.0077808] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2013] [Accepted: 09/05/2013] [Indexed: 02/08/2023] Open
Abstract
The human pathogen Listeria monocytogenes is susceptible to the β-lactam antibiotics penicillin G and ampicillin, and these are the drugs of choice for the treatment of listerial infections. However, these antibiotics exert only a bacteriostatic effect on this bacterium and consequently, L. monocytogenes is regarded as β-lactam tolerant. It is widely accepted that the phenomenon of bacterial tolerance to β-lactams is due to the lack of adequate autolysin activity, but the mechanisms of L. monocytogenes tolerance to this class of antibiotics are poorly characterized. A ferritin-like protein (Fri) was recently identified as a mediator of β-lactam tolerance in L. monocytogenes, but its function in this process remains unknown. The present study was undertaken to improve our understanding of L. monocytogenes tolerance to β-lactams and to characterize the role of Fri in this phenomenon. A comparative physiological analysis of wild-type L. monocytogenes and a fri deletion mutant provided evidence of a multilevel mechanism controlling autolysin activity in cells grown under β-lactam pressure, which leads to a reduction in the level and/or activity of cell wall-associated autolysins. This is accompanied by increases in the amount of teichoic acids, cell wall thickness and cell envelope integrity of L. monocytogenes grown in the presence of penicillin G, and provides the basis for the innate β-lactam tolerance of this bacterium. Furthermore, this study revealed the inability of the L. monocytogenes Δ fri mutant to deplete autolysins from the cell wall, to adjust the content of teichoic acids and to maintain their D-alanylation at the correct level when treated with penicillin G, thus providing further evidence that Fri is involved in the control of L. monocytogenes cell envelope structure and stability under β-lactam pressure.
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Affiliation(s)
- Agata Krawczyk-Balska
- Department of Applied Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Magdalena Lipiak
- Department of Applied Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland
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10
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Use of a bacteriophage lysin to identify a novel target for antimicrobial development. PLoS One 2013; 8:e60754. [PMID: 23593301 PMCID: PMC3622686 DOI: 10.1371/journal.pone.0060754] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 03/02/2013] [Indexed: 11/19/2022] Open
Abstract
We identified an essential cell wall biosynthetic enzyme in Bacillus anthracis and an inhibitor thereof to which the organism did not spontaneously evolve measurable resistance. This work is based on the exquisite binding specificity of bacteriophage-encoded cell wall-hydrolytic lysins, which have evolved to recognize critical receptors within the bacterial cell wall. Focusing on the B. anthracis-specific PlyG lysin, we first identified its unique cell wall receptor and cognate biosynthetic pathway. Within this pathway, one biosynthetic enzyme, 2-epimerase, was required for both PlyG receptor expression and bacterial growth. The 2-epimerase was used to design a small-molecule inhibitor, epimerox. Epimerox prevented growth of several Gram-positive pathogens and rescued mice challenged with lethal doses of B. anthracis. Importantly, resistance to epimerox was not detected (<10(-11) frequency) in B. anthracis and S. aureus. These results describe the use of phage lysins to identify promising lead molecules with reduced resistance potential for antimicrobial development.
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11
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Wall teichoic acids restrict access of bacteriophage endolysin Ply118, Ply511, and PlyP40 cell wall binding domains to the Listeria monocytogenes peptidoglycan. J Bacteriol 2012; 194:6498-506. [PMID: 23002226 DOI: 10.1128/jb.00808-12] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The C-terminal cell wall binding domains (CBDs) of phage endolysins direct the enzymes to their binding ligands on the bacterial cell wall with high affinity and specificity. The Listeria monocytogenes Ply118, Ply511, and PlyP40 endolysins feature related CBDs which recognize the directly cross-linked peptidoglycan backbone structure of Listeria. However, decoration with fluorescently labeled CBDs primarily occurs at the poles and septal regions of the rod-shaped cells. To elucidate the potential role of secondary cell wall-associated carbohydrates such as the abundant wall teichoic acid (WTA) on this phenomenon, we investigated CBD binding using L. monocytogenes serovar 1/2 and 4 cells deficient in WTA. Mutants were obtained by deletion of two redundant tagO homologues, whose products catalyze synthesis of the WTA linkage unit. While inactivation of either tagO1 (EGDe lmo0959) or tagO2 (EGDe lmo2519) alone did not affect WTA content, removal of both alleles following conditional complementation yielded WTA-deficient Listeria cells. Substitution of tagO from an isopropyl-β-d-thiogalactopyranoside-inducible single-copy integration vector restored the original phenotype. Although WTA-deficient cells are viable, they featured severe growth inhibition and an unusual coccoid morphology. In contrast to CBDs from other Listeria phage endolysins which directly utilize WTA as binding ligand, the data presented here show that WTAs are not required for attachment of CBD118, CBD511, and CBDP40. Instead, lack of the cell wall polymers enables unrestricted spatial access of CBDs to the cell wall surface, indicating that the abundant WTA can negatively regulate sidewall localization of the cell wall binding domains.
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12
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Heuston S, Begley M, Davey MS, Eberl M, Casey PG, Hill C, Gahan CGM. HmgR, a key enzyme in the mevalonate pathway for isoprenoid biosynthesis, is essential for growth of Listeria monocytogenes EGDe. MICROBIOLOGY-SGM 2012; 158:1684-1693. [PMID: 22504435 DOI: 10.1099/mic.0.056069-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Isoprenoids may be synthesized via one of two pathways, the classical mevalonate pathway or the alternative 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway. While the majority of bacteria utilize a single pathway for isoprenoid biosynthesis, Listeria monocytogenes is unusual in possessing the complete set of genes for both pathways. Here, we utilized new molecular tools to create precise gene deletions in selected genes encoding enzymes of both pathways, gcpE, lytB (encoding proteins in the MEP pathway) and hmgR (encoding a protein in the mevalonate pathway). We demonstrate that the hmgR gene can only be deleted when the growth medium is supplemented with exogenous mevalonate. Furthermore, full growth of the mutant in the absence of mevalonate was only possible when the intact hmgR gene was supplied in trans using an IPTG-inducible expression system. Murine competitive index assays performed via the oral and intraperitoneal routes of infection revealed that the mevalonate hmgR mutant could not be recovered from livers and spleens 3 days post-infection. We propose that HmgR in L. monocytogenes EGDe is involved in essential metabolic functions and that an intact MEP pathway is not capable of sustaining growth.
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Affiliation(s)
- Sinead Heuston
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland.,Department of Microbiology, University College Cork, Cork, Ireland
| | - Máire Begley
- Department of Microbiology, University College Cork, Cork, Ireland
| | - Martin S Davey
- Department of Infection, Immunity and Biochemistry, School of Medicine, Cardiff University, Cardiff, UK
| | - Matthias Eberl
- Department of Infection, Immunity and Biochemistry, School of Medicine, Cardiff University, Cardiff, UK
| | - Pat G Casey
- Department of Microbiology, University College Cork, Cork, Ireland
| | - Colin Hill
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland.,Department of Microbiology, University College Cork, Cork, Ireland
| | - Cormac G M Gahan
- School of Pharmacy, University College Cork, Cork, Ireland.,Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland.,Department of Microbiology, University College Cork, Cork, Ireland
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13
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Popowska M, Osińska M, Rzeczkowska M. N-acetylglucosamine-6-phosphate deacetylase (NagA) of Listeria monocytogenes EGD, an essential enzyme for the metabolism and recycling of amino sugars. Arch Microbiol 2012; 194:255-68. [PMID: 21947170 PMCID: PMC3304070 DOI: 10.1007/s00203-011-0752-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2011] [Revised: 08/25/2011] [Accepted: 08/27/2011] [Indexed: 02/01/2023]
Abstract
The main aim of our study was to determine the physiological function of NagA enzyme in the Listeria monocytogenes cell. The primary structure of the murein of L. monocytogenes is very similar to that of Escherichia coli, the main differences being amidation of diaminopimelic acid and partial de-N-acetylation of glucosamine residues. NagA is needed for the deacetylation of N-acetyl-glucosamine-6 phosphate to glucosamine-6 phosphate and acetate. Analysis of the L. monocytogenes genome reveals the presence of two proteins with NagA domain, Lmo0956 and Lmo2108, which are cytoplasmic putative proteins. We introduced independent mutations into the structural genes for the two proteins. In-depth characterization of one of these mutants, MN1, deficient in protein Lmo0956 revealed strikingly altered cell morphology, strongly reduced cell wall murein content and decreased sensitivity to cell wall hydrolase, mutanolysin and peptide antibiotic, colistin. The gene products of operon 150, consisting of three genes: lmo0956, lmo0957, and lmo0958, are necessary for the cytosolic steps of the amino-sugar-recycling pathway. The cytoplasmic de-N-acetylase Lmo0956 of L. monocytogenes is required for cell wall peptidoglycan and teichoic acid biosynthesis and is also essential for bacterial cell growth, cell division, and sensitivity to cell wall hydrolases and peptide antibiotics.
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Affiliation(s)
- Magdalena Popowska
- Department of Applied Microbiology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Poland.
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14
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Davis R, Mauer LJ. Subtyping of Listeria monocytogenes at the haplotype level by Fourier transform infrared (FT-IR) spectroscopy and multivariate statistical analysis. Int J Food Microbiol 2011; 150:140-9. [DOI: 10.1016/j.ijfoodmicro.2011.07.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Revised: 06/24/2011] [Accepted: 07/23/2011] [Indexed: 10/17/2022]
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15
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Loepfe C, Raimann E, Stephan R, Tasara T. Reduced host cell invasiveness and oxidative stress tolerance in double and triple csp gene family deletion mutants of Listeria monocytogenes. Foodborne Pathog Dis 2010; 7:775-83. [PMID: 20184451 DOI: 10.1089/fpd.2009.0458] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The cold shock protein (Csp) family comprises small, highly conserved proteins that bind nucleic acids to modulate various bacterial gene expressions. In addition to cold adaptation functions, this group of proteins is thought to facilitate various cellular processes to promote normal growth and stress adaptation responses. Three proteins making up the Listeria monocytogenes Csp family (CspA, CspB, and CspD) promote both cold and osmotic stress adaptation functions in this bacterium. The contribution of these three Csps in the host cell invasion processes of L. monocytogenes was investigated based on human Caco-2 and murine macrophage in vitro cell infection models. The DeltacspB, DeltacspD, DeltacspAB, DeltacspAD, DeltacspBD, and DeltacspABD strains were all significantly impaired in Caco-2 cell invasion compared with the wild-type strain, whereas in the murine macrophage infection assay only, the double (DeltacspBD) and triple (DeltacspABD) csp mutants were also significantly impaired in cell invasion compared with the wild-type strain. The DeltacspBD and DeltacspABD mutants displayed the most severely impaired invasion phenotypes. The invasion ability of these two mutant strains was also further analyzed using cold-stress-exposed organisms. In both cell infection models a significant reduction in invasiveness was observed after cold stress exposure of Listeria organisms. The negative impact of cold stress on subsequent cell invasion ability was, however, more severe in cold-sensitive csp mutants (DeltacspBD and DeltacspABD) compared with the wild type. The impaired macrophage invasion and intracellular growth of DeltacspBD and DeltacspABD also led us to examine oxidative stress resistance capacity in these two mutant strains. Both strains also displayed higher oxidative stress sensitivity relative to the wild-type strain. Our data indicate that besides cold and osmotic stress adaptation roles, Csp family proteins also promote efficient host cell invasion and oxidative stress adaptation processes in L. monocytogenes.
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Affiliation(s)
- Chantal Loepfe
- Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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Brunner J, Scheres N, El Idrissi NB, Deng DM, Laine ML, van Winkelhoff AJ, Crielaard W. The capsule of Porphyromonas gingivalis reduces the immune response of human gingival fibroblasts. BMC Microbiol 2010; 10:5. [PMID: 20064245 PMCID: PMC2817674 DOI: 10.1186/1471-2180-10-5] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Accepted: 01/11/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Periodontitis is a bacterial infection of the periodontal tissues. The Gram-negative anaerobic bacterium Porphyromonas gingivalis is considered a major causative agent. One of the virulence factors of P. gingivalis is capsular polysaccharide (CPS). Non-encapsulated strains have been shown to be less virulent in mouse models than encapsulated strains. RESULTS To examine the role of the CPS in host-pathogen interactions we constructed an insertional isogenic P. gingivalis knockout in the epimerase-coding gene epsC that is located at the end of the CPS biosynthesis locus. This mutant was subsequently shown to be non-encapsulated. K1 capsule biosynthesis could be restored by in trans expression of an intact epsC gene. We used the epsC mutant, the W83 wild type strain and the complemented mutant to challenge human gingival fibroblasts to examine the immune response by quantification of IL-1beta, IL-6 and IL-8 transcription levels. For each of the cytokines significantly higher expression levels were found when fibroblasts were challenged with the epsC mutant compared to those challenged with the W83 wild type, ranging from two times higher for IL-1beta to five times higher for IL-8. CONCLUSIONS These experiments provide the first evidence that P. gingivalis CPS acts as an interface between the pathogen and the host that may reduce the host's pro-inflammatory immune response. The higher virulence of encapsulated strains may be caused by this phenomenon which enables the bacteria to evade the immune system.
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Affiliation(s)
- Jorg Brunner
- Department of Oral Microbiology, Academic Centre for Dentistry Amsterdam, Universiteit van Amsterdam and Vrije Universiteit, Amsterdam, The Netherlands.
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Beganović J, Guillot A, van de Guchte M, Jouan A, Gitton C, Loux V, Roy K, Huet S, Monod H, Monnet V. Characterization of the Insoluble Proteome of Lactococcus lactis by SDS-PAGE LC-MS/MS Leads to the Identification of New Markers of Adaptation of the Bacteria to the Mouse Digestive Tract. J Proteome Res 2010; 9:677-88. [DOI: 10.1021/pr9000866] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Jasna Beganović
- INRA, PAPPSO (Plate-Forme d’Analyse Protéomique de Paris Sud-Ouest), UR895 Génétique Microbienne, UR341 Mathématique et Informatique Appliquées, UR477 Biochimie Bactérienne, UR1077 Mathématique, Informatique, Génome, Domaine de Vilvert, F-78352 Jouy en Josas, France
| | - Alain Guillot
- INRA, PAPPSO (Plate-Forme d’Analyse Protéomique de Paris Sud-Ouest), UR895 Génétique Microbienne, UR341 Mathématique et Informatique Appliquées, UR477 Biochimie Bactérienne, UR1077 Mathématique, Informatique, Génome, Domaine de Vilvert, F-78352 Jouy en Josas, France
| | - Maarten van de Guchte
- INRA, PAPPSO (Plate-Forme d’Analyse Protéomique de Paris Sud-Ouest), UR895 Génétique Microbienne, UR341 Mathématique et Informatique Appliquées, UR477 Biochimie Bactérienne, UR1077 Mathématique, Informatique, Génome, Domaine de Vilvert, F-78352 Jouy en Josas, France
| | - Anne Jouan
- INRA, PAPPSO (Plate-Forme d’Analyse Protéomique de Paris Sud-Ouest), UR895 Génétique Microbienne, UR341 Mathématique et Informatique Appliquées, UR477 Biochimie Bactérienne, UR1077 Mathématique, Informatique, Génome, Domaine de Vilvert, F-78352 Jouy en Josas, France
| | - Christophe Gitton
- INRA, PAPPSO (Plate-Forme d’Analyse Protéomique de Paris Sud-Ouest), UR895 Génétique Microbienne, UR341 Mathématique et Informatique Appliquées, UR477 Biochimie Bactérienne, UR1077 Mathématique, Informatique, Génome, Domaine de Vilvert, F-78352 Jouy en Josas, France
| | - Valentin Loux
- INRA, PAPPSO (Plate-Forme d’Analyse Protéomique de Paris Sud-Ouest), UR895 Génétique Microbienne, UR341 Mathématique et Informatique Appliquées, UR477 Biochimie Bactérienne, UR1077 Mathématique, Informatique, Génome, Domaine de Vilvert, F-78352 Jouy en Josas, France
| | - Karine Roy
- INRA, PAPPSO (Plate-Forme d’Analyse Protéomique de Paris Sud-Ouest), UR895 Génétique Microbienne, UR341 Mathématique et Informatique Appliquées, UR477 Biochimie Bactérienne, UR1077 Mathématique, Informatique, Génome, Domaine de Vilvert, F-78352 Jouy en Josas, France
| | - Sylvie Huet
- INRA, PAPPSO (Plate-Forme d’Analyse Protéomique de Paris Sud-Ouest), UR895 Génétique Microbienne, UR341 Mathématique et Informatique Appliquées, UR477 Biochimie Bactérienne, UR1077 Mathématique, Informatique, Génome, Domaine de Vilvert, F-78352 Jouy en Josas, France
| | - Hervé Monod
- INRA, PAPPSO (Plate-Forme d’Analyse Protéomique de Paris Sud-Ouest), UR895 Génétique Microbienne, UR341 Mathématique et Informatique Appliquées, UR477 Biochimie Bactérienne, UR1077 Mathématique, Informatique, Génome, Domaine de Vilvert, F-78352 Jouy en Josas, France
| | - Véronique Monnet
- INRA, PAPPSO (Plate-Forme d’Analyse Protéomique de Paris Sud-Ouest), UR895 Génétique Microbienne, UR341 Mathématique et Informatique Appliquées, UR477 Biochimie Bactérienne, UR1077 Mathématique, Informatique, Génome, Domaine de Vilvert, F-78352 Jouy en Josas, France
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Faith N, Kathariou S, Cheng Y, Promadej N, Neudeck BL, Zhang Q, Luchansky J, Czuprynski C. The role of L. monocytogenes serotype 4b gtcA in gastrointestinal listeriosis in A/J mice. Foodborne Pathog Dis 2010; 6:39-48. [PMID: 18991548 DOI: 10.1089/fpd.2008.0154] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Serotype 4b strains of Listeria monocytogenes have been responsible for most large outbreaks of listeriosis. In L. monocytogenes serotype 4b, gtcA and gltA have been implicated in serotype-specific glycosylation of the teichoic acid of the cell wall with galactose and glucose. In this study, we investigated the impact of mutations in gltA (resulting in absence of glucose on teichoic acid) and gtcA (resulting in absence of galactose, and markedly reduced glucose on teichoic acid) on virulence following intragastric infection of anesthetized A/J mice. The gltA mutant was not impaired in virulence in this model. In contrast, testing of gtcA mutants constructed in two different strains showed that the mutants were recovered in lower numbers than their respective parent strains from the spleen, liver, ceca, and gall bladders of intragastrically inoculated mice. Genetic complementation of the gtcA mutation partially restored gastrointestinal virulence. When mice were inoculated intravenously, the gtcA mutants were also recovered in lower numbers from the liver (for both mutant strains) and the spleen (for one mutant strain) than their respective parental strains. The mutants were also evaluated for invasion and intracellular multiplication in the Caco-2 human intestinal epithelial cell line. Inactivation of gltA did not affect invasion or intracellular growth of the bacteria. In contrast, gtcA mutants showed decreased invasion, but normal multiplication in Caco-2 cells. Overall, these data demonstrate a role for gtcA in the pathogenesis of gastrointestinal listeriosis in mice, and suggest that diminished ability of gtcA mutants to invade intestinal epithelial cells may be partly responsible for decreased gastrointestinal virulence.
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Affiliation(s)
- Nancy Faith
- School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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Xia G, Kohler T, Peschel A. The wall teichoic acid and lipoteichoic acid polymers of Staphylococcus aureus. Int J Med Microbiol 2009; 300:148-54. [PMID: 19896895 DOI: 10.1016/j.ijmm.2009.10.001] [Citation(s) in RCA: 168] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Staphylococci and most other Gram-positive bacteria incorporate complex teichoic acid (TA) polymers into their cell envelopes. Several crucial roles in Staphylococcus aureus fitness and cell wall maintenance have been assigned to these polymers, which are either covalently linked to peptidoglycan (wall teichoic acid, WTA) or to the cytoplasmic membrane (lipoteichoic acid, LTA). However, the exact TA structures, functions, and biosynthetic pathways are only superficially understood. Recently, most of the enzymes mediating TA biosynthesis have been identified and mutants lacking or with defined changes in WTA or LTA have become available. Their characterization has revealed crucial roles of TAs in protection against harmful molecules and environmental stresses; in control of enzymes directing cell division or morphogenesis and of cation homeostasis; and in interaction with host or bacteriophage receptors and biomaterials. Accordingly, several in vivo studies have demonstrated the importance of WTA and LTA in S. aureus colonization, infection, and immune evasion. TAs and enzymes required for TA biosynthesis represent attractive candidates for novel vaccines and antibiotics and are targeted by recently developed antibacterial therapeutics.
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Affiliation(s)
- Guoqing Xia
- Division of Cellular and Molecular Microbiology, Institute of Medical Microbiology and Hygiene, University of Tübingen, Elfriede-Aulhorn-Strasse 6, D-72076 Tübingen, Germany
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Abstract
We describe the development of genetic tools for regulated gene expression, the introduction of chromosomal mutations, and improved plasmid transfer by electroporation in the food-borne pathogen Listeria monocytogenes. pIMK, a kanamycin-resistant, site-specific, integrative listeriophage vector was constructed and then modified for overexpression (pIMK2) or for isopropyl-beta-d-thiogalactopyranoside (IPTG)-regulated expression (pIMK3 and pIMK4). The dynamic range of promoters was assessed by determining luciferase activity, P60 secretion, and internalin A-mediated invasion. These analyses demonstrated that pIMK4 and pIMK3 have a stringently controlled dynamic range of 540-fold. Stable gene overexpression was achieved with pIMK2, giving a range of expression for the three vectors of 1,350-fold. The lactococcal pORI280 system was optimized for the generation of chromosomal mutations and used to create five new prfA star mutants. The combination of pIMK4 and pORI280 allowed streamlined creation of "IPTG-dependent" mutants. This was exemplified by creation of a clean deletion mutant with deletion of the universally essential secA gene, and this mutant exhibited a rapid loss of viability upon withdrawal of IPTG. We also improved plasmid transfer by electroporation into three commonly used laboratory strains of L. monocytogenes. A 125-fold increase in transformation efficiency for EGDe compared with the widely used protocol of Park and Stewart (S. F. Park and G. S. Stewart, Gene 94:129-132, 1990) was observed. Maximal transformation efficiencies of 5.7 x 10(6) and 6.7 x 10(6) CFU per mug were achieved for EGDe and 10403S, respectively, with a replicating plasmid. An efficiency of 2 x 10(7) CFU per mug is the highest efficiency reported thus far for L. monocytogenes F2365.
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22
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A structural basis for the allosteric regulation of non-hydrolysing UDP-GlcNAc 2-epimerases. EMBO Rep 2008; 9:199-205. [PMID: 18188181 DOI: 10.1038/sj.embor.7401154] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2007] [Revised: 11/08/2007] [Accepted: 11/19/2007] [Indexed: 11/08/2022] Open
Abstract
The non-hydrolysing bacterial UDP-N-acetylglucosamine 2-epimerase (UDP-GlcNAc 2-epimerase) catalyses the conversion of UDP-GlcNAc into UDP-N-acetylmannosamine, an intermediate in the biosynthesis of several cell-surface polysaccharides. This enzyme is allosterically regulated by its substrate UDP-GlcNAc. The structure of the ternary complex between the Bacillus anthracis UDP-GlcNAc 2-epimerase, its substrate UDP-GlcNAc and the reaction intermediate UDP, showed direct interactions between UDP and its substrate, and between the complex and highly conserved enzyme residues, identifying the allosteric site of the enzyme. The binding of UDP-GlcNAc is associated with conformational changes in the active site of the enzyme. Kinetic data and mutagenesis of the highly conserved UDP-GlcNAc-interacting residues confirm their importance in the substrate binding and catalysis of the enzyme. This constitutes the first example to our knowledge, of an enzymatic allosteric activation by direct interaction between the substrate and the allosteric activator.
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Abstract
Multiple resistant staphylococci that cause significant morbidity and mortality are the leading cause of nosocomial infections. Meanwhile, methicillin-resistant Staphylococcus aureus (MRSA) also spreads in the community, where highly virulent strains infect children and young adults who have no predisposing risk factors. Although some treatment options remain, the search for new antibacterial targets and lead compounds is urgently required to ensure that staphylococcal infections can be effectively treated in the future. Promising targets for new antibacterials are gene products that are involved in essential cell functions. In addition to antibacterials, active and passive immunization strategies are being developed that target surface components of staphylococci such as cell wall-linked adhesins, teichoic acids and capsule or immunodominant antigens.
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Affiliation(s)
- Knut Ohlsen
- University of Würzburg, Institute for Molecular Infection Biology, Röntgenring 11, 97070 Würzburg, Germany
| | - Udo Lorenz
- University of Würzburg, Centre for Operative Medicine, Department of Surgery I, Oberdürrbacher Str. 6, 97080 Würzburg, Germany
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Liu D, Lawrence ML, Ainsworth AJ, Austin FW. Toward an improved laboratory definition of Listeria monocytogenes virulence. Int J Food Microbiol 2007; 118:101-15. [PMID: 17727992 DOI: 10.1016/j.ijfoodmicro.2007.07.045] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Revised: 04/07/2007] [Accepted: 07/28/2007] [Indexed: 11/23/2022]
Abstract
Listeria monocytogenes is an opportunistic foodborne pathogen that encompasses a diversity of strains with varied virulence. The ability to rapidly determine the pathogenic potential of L. monocytogenes strains is integral to the control and prevention campaign against listeriosis. Early methods for assessing L. monocytogenes virulence include in vivo bioassays and in vitro cell assays. While in vivo bioassays provide a measurement of all virulence determinants of L. monocytogenes, they are not applied routinely due to their reliance on experimental animals whose costs have become increasingly prohibitive. As a low cost alternative, in vitro cell assays are useful for estimating the virulence of L. monocytogenes strains. However, these assays are often slow, and at times variable. Prior attempts to ascertain L. monocytogenes virulence by targeting virulence-associated proteins and genes have been largely unsuccessful, since many of the assay targets are present in both virulent and avirulent strains. Recent identification of novel virulence-specific genes (particularly internalin gene inlJ) has opened a new avenue for rapid, sensitive, and precise differentiation of virulent L. monocytogenes strains from avirulent strains. The application of DNA sequencing technique also offers an additional tool for assessing L. monocytogenes virulence potential. By providing an update on the laboratory methods that have been reported for the determination of L. monocytogenes pathogenicity, this review discusses future research needs that may help achieve an improved laboratory definition of L. monocytogenes virulence.
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Affiliation(s)
- Dongyou Liu
- College of Veterinary Medicine, Mississippi State University, PO Box 6100, Mississippi State, MS 39762, USA.
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