LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 16

Search options

  1. Article ; Online: The Staphylococcus aureus CamS lipoprotein is a repressor of toxin production that shapes host-pathogen interaction.

    Schilcher, Katrin / Severn, Morgan M / Jenul, Christian / Avina, Young-Saeng C / Keogh, Rebecca A / Horswill, Alexander R

    PLoS biology

    2024  Volume 22, Issue 1, Page(s) e3002451

    Abstract: Lipoproteins of the opportunistic pathogen Staphylococcus aureus play a crucial role in various cellular processes and host interactions. Consisting of a protein and a lipid moiety, they support nutrient acquisition and anchor the protein to the ... ...

    Abstract Lipoproteins of the opportunistic pathogen Staphylococcus aureus play a crucial role in various cellular processes and host interactions. Consisting of a protein and a lipid moiety, they support nutrient acquisition and anchor the protein to the bacterial membrane. Recently, we identified several processed and secreted small linear peptides that derive from the secretion signal sequence of S. aureus lipoproteins. Here, we show, for the first time, that the protein moiety of the S. aureus lipoprotein CamS has a biological role that is distinct from its associated linear peptide staph-cAM373. The small peptide was shown to be involved in interspecies horizontal gene transfer, the primary mechanism for the dissemination of antibiotic resistance among bacteria. We provide evidence that the CamS protein moiety is a potent repressor of cytotoxins, such as α-toxin and leukocidins. The CamS-mediated suppression of toxin transcription was reflected by altered disease severity in in vivo infection models involving skin and soft tissue, as well as bloodstream infections. Collectively, we have uncovered the role of the protein moiety of the staphylococcal lipoprotein CamS as a previously uncharacterized repressor of S. aureus toxin production, which consequently regulates virulence and disease outcomes. Notably, the camS gene is conserved in S. aureus, and we also demonstrated the muted transcriptional response of cytotoxins in 2 different S. aureus lineages. Our findings provide the first evidence of distinct biological functions of the protein moiety and its associated linear peptide for a specific lipoprotein. Therefore, lipoproteins in S. aureus consist of 3 functional components: a lipid moiety, a protein moiety, and a small linear peptide, with putative different biological roles that might not only determine the outcome of host-pathogen interactions but also drive the acquisition of antibiotic resistance determinants.
    MeSH term(s) Humans ; Staphylococcus aureus/genetics ; Lipoproteins/genetics ; Staphylococcal Infections ; Host-Pathogen Interactions ; Cell Adhesion Molecules ; Cytotoxins ; Peptides
    Chemical Substances Lipoproteins ; Cell Adhesion Molecules ; Cytotoxins ; Peptides
    Language English
    Publishing date 2024-01-05
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2126776-5
    ISSN 1545-7885 ; 1544-9173
    ISSN (online) 1545-7885
    ISSN 1544-9173
    DOI 10.1371/journal.pbio.3002451
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article ; Online: Regulation of

    Jenul, Christian / Horswill, Alexander R

    Microbiology spectrum

    2019  Volume 7, Issue 2

    Abstract: Staphylococcus ... ...

    Abstract Staphylococcus aureus
    MeSH term(s) Adhesins, Bacterial/genetics ; Adhesins, Bacterial/metabolism ; Animals ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Bacterial Toxins/genetics ; Bacterial Toxins/metabolism ; Humans ; Staphylococcal Infections/microbiology ; Staphylococcus aureus/genetics ; Staphylococcus aureus/metabolism ; Staphylococcus aureus/pathogenicity ; Virulence ; Virulence Factors/genetics ; Virulence Factors/metabolism
    Chemical Substances Adhesins, Bacterial ; Bacterial Proteins ; Bacterial Toxins ; Virulence Factors
    Language English
    Publishing date 2019-04-05
    Publishing country United States
    Document type Journal Article ; Review
    ISSN 2165-0497
    ISSN (online) 2165-0497
    DOI 10.1128/microbiolspec.GPP3-0031-2018
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  3. Article ; Online: Biosynthesis and Structure-Activity Relationship Investigations of the Diazeniumdiolate Antifungal Agent Fragin.

    Sieber, Simon / Daeppen, Christophe / Jenul, Christian / Mannancherril, Vidya / Eberl, Leo / Gademann, Karl

    Chembiochem : a European journal of chemical biology

    2020  Volume 21, Issue 11, Page(s) 1587–1592

    Abstract: Only a few natural products incorporating a diazeniumdiolate moiety have been isolated, and these compounds usually display a broad range of biological activities. Only recently has the first diazeniumdiolate natural product biosynthetic gene cluster ... ...

    Abstract Only a few natural products incorporating a diazeniumdiolate moiety have been isolated, and these compounds usually display a broad range of biological activities. Only recently has the first diazeniumdiolate natural product biosynthetic gene cluster been identified in Burkholderia cenocepacia H111, which produces the fungicide (-)-fragin and the signal molecule rac-valdiazen. In this study, l-valine was identified as the initial substrate of (-)-fragin biosynthesis with the aid of feeding experiments using isotopically labelled amino acid. The formation of the diazeniumdiolate was chemically studied with several proposed intermediates. Our results indicate that the functional group is formed during an early stage of the biosynthesis. Furthermore, an oxime compound was identified as a degradation product of (-)-fragin and was also observed in the crude extract of the wild-type strain. Moreover, a structure-activity relationship analysis revealed that each moiety of (-)-fragin is essential for its biological activity.
    MeSH term(s) Antifungal Agents/chemistry ; Antifungal Agents/metabolism ; Antifungal Agents/pharmacology ; Azo Compounds/chemistry ; Azo Compounds/metabolism ; Azo Compounds/pharmacology ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Biological Products/chemistry ; Biological Products/metabolism ; Biological Products/pharmacology ; Burkholderia cenocepacia/enzymology ; Burkholderia cenocepacia/genetics ; Genome, Bacterial ; Gram-Negative Bacteria/drug effects ; Gram-Negative Bacteria/growth & development ; Gram-Positive Bacteria/drug effects ; Gram-Positive Bacteria/growth & development ; Microbial Sensitivity Tests ; Multigene Family ; Oxidoreductases/genetics ; Oxidoreductases/metabolism ; Structure-Activity Relationship ; Substrate Specificity ; Valine/chemistry ; Valine/metabolism
    Chemical Substances Antifungal Agents ; Azo Compounds ; Bacterial Proteins ; Biological Products ; diazeniumdiolate ; Oxidoreductases (EC 1.-) ; Valine (HG18B9YRS7)
    Language English
    Publishing date 2020-03-04
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2020469-3
    ISSN 1439-7633 ; 1439-4227
    ISSN (online) 1439-7633
    ISSN 1439-4227
    DOI 10.1002/cbic.201900755
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  4. Article ; Online: Pyochelin biotransformation by Staphylococcus aureus shapes bacterial competition with Pseudomonas aeruginosa in polymicrobial infections.

    Jenul, Christian / Keim, Klara C / Jens, Justin N / Zeiler, Michael J / Schilcher, Katrin / Schurr, Michael J / Melander, Christian / Phelan, Vanessa V / Horswill, Alexander R

    Cell reports

    2023  Volume 42, Issue 6, Page(s) 112540

    Abstract: Pseudomonas aeruginosa and Staphylococcus aureus are among the most frequently isolated bacterial species from polymicrobial infections of patients with cystic fibrosis and chronic wounds. We apply mass spectrometry guided interaction studies to ... ...

    Abstract Pseudomonas aeruginosa and Staphylococcus aureus are among the most frequently isolated bacterial species from polymicrobial infections of patients with cystic fibrosis and chronic wounds. We apply mass spectrometry guided interaction studies to determine how chemical interaction shapes the fitness and community structure during co-infection of these two pathogens. We demonstrate that S. aureus is equipped with an elegant mechanism to inactivate pyochelin via the yet uncharacterized methyltransferase Spm (staphylococcal pyochelin methyltransferase). Methylation of pyochelin abolishes the siderophore activity of pyochelin and significantly lowers pyochelin-mediated intracellular reactive oxygen species (ROS) production in S. aureus. In a murine wound co-infection model, an S. aureus mutant unable to methylate pyochelin shows significantly lower fitness compared with its parental strain. Thus, Spm-mediated pyochelin methylation is a mechanism to increase S. aureus survival during in vivo competition with P. aeruginosa.
    MeSH term(s) Humans ; Mice ; Animals ; Staphylococcus aureus/physiology ; Pseudomonas aeruginosa/metabolism ; Coinfection/microbiology ; Staphylococcal Infections/microbiology
    Chemical Substances pyochelin (69772-54-9)
    Language English
    Publishing date 2023-05-24
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 2649101-1
    ISSN 2211-1247 ; 2211-1247
    ISSN (online) 2211-1247
    ISSN 2211-1247
    DOI 10.1016/j.celrep.2023.112540
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  5. Article ; Online: Targeted and untargeted analysis of secondary metabolites to monitor growth and quorum sensing inhibition for methicillin-resistant Staphylococcus aureus (MRSA).

    Jones, Derick D / Caesar, Lindsay K / Pelzer, Chantal V / Crandall, William J / Jenul, Christian / Todd, Daniel A / Horswill, Alexander R / Cech, Nadja B

    Journal of microbiological methods

    2020  Volume 176, Page(s) 106000

    Abstract: Drug resistant infections are an increasing problem world-wide, responsible for an estimated 700,000 annual mortalities. The use of antibiotics to treat such infections has resulted in the development of resistant bacterial pathogens such as methicillin- ... ...

    Abstract Drug resistant infections are an increasing problem world-wide, responsible for an estimated 700,000 annual mortalities. The use of antibiotics to treat such infections has resulted in the development of resistant bacterial pathogens such as methicillin-resistant Staphylococcus aureus (MRSA). One potential alternative strategy for treating drug resistant bacterial infections is to inhibit the production of toxins, thereby making the bacteria less harmful to the host, a so called "anti-virulence" approach. In MRSA, the agr quorum sensing system is one of the major regulators of toxin production, and quorum sensing inhibitors that target this system are a promising anti-virulence strategy. With this study, we developed a method that enables the activity of quorum sensing inhibitors to be measured using ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-MS). This method is an improvement over existing methods because it can be employed to distinguish antimicrobial activity from quorum sensing inhibition activity based on the UPLC-MS data. This is possible by simultaneously tracking production of metabolites regulated by the agr quorum sensing system (AIP-I and formylated δ-toxin) and a metabolite that appears not to be agr regulated under the conditions of this study (aureusimine B). The newly developed method provides more nuanced indication of how metabolite production changes over time and in response to quorum sensing or growth inhibition than is possible with commonly employed spectroscopic methods.
    MeSH term(s) Bacterial Proteins/antagonists & inhibitors ; Chromatography, High Pressure Liquid ; Methicillin-Resistant Staphylococcus aureus/growth & development ; Methicillin-Resistant Staphylococcus aureus/metabolism ; Pyrazines/analysis ; Quorum Sensing ; Tandem Mass Spectrometry ; Trans-Activators/antagonists & inhibitors
    Chemical Substances Agr protein, Staphylococcus aureus ; Bacterial Proteins ; Pyrazines ; Trans-Activators ; phevalin
    Language English
    Publishing date 2020-07-07
    Publishing country Netherlands
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 604916-3
    ISSN 1872-8359 ; 0167-7012
    ISSN (online) 1872-8359
    ISSN 0167-7012
    DOI 10.1016/j.mimet.2020.106000
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  6. Article: Targeted and untargeted analysis of secondary metabolites to monitor growth and quorum sensing inhibition for methicillin-resistant Staphylococcus aureus (MRSA)

    Jones, Derick D / Caesar, Lindsay K / Pelzer, Chantal V / Crandall, William J / Jenul, Christian / Todd, Daniel A / Horswill, Alexander R / Cech, Nadja B

    Journal of microbiological methods. 2020 Sept., v. 176

    2020  

    Abstract: Drug resistant infections are an increasing problem world-wide, responsible for an estimated 700,000 annual mortalities. The use of antibiotics to treat such infections has resulted in the development of resistant bacterial pathogens such as methicillin- ... ...

    Abstract Drug resistant infections are an increasing problem world-wide, responsible for an estimated 700,000 annual mortalities. The use of antibiotics to treat such infections has resulted in the development of resistant bacterial pathogens such as methicillin-resistant Staphylococcus aureus (MRSA). One potential alternative strategy for treating drug resistant bacterial infections is to inhibit the production of toxins, thereby making the bacteria less harmful to the host, a so called “anti-virulence” approach. In MRSA, the agr quorum sensing system is one of the major regulators of toxin production, and quorum sensing inhibitors that target this system are a promising anti-virulence strategy. With this study, we developed a method that enables the activity of quorum sensing inhibitors to be measured using ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-MS). This method is an improvement over existing methods because it can be employed to distinguish antimicrobial activity from quorum sensing inhibition activity based on the UPLC-MS data. This is possible by simultaneously tracking production of metabolites regulated by the agr quorum sensing system (AIP-I and formylated δ-toxin) and a metabolite that appears not to be agr regulated under the conditions of this study (aureusimine B). The newly developed method provides more nuanced indication of how metabolite production changes over time and in response to quorum sensing or growth inhibition than is possible with commonly employed spectroscopic methods.
    Keywords antimicrobial properties ; growth retardation ; mass spectrometry ; methicillin-resistant Staphylococcus aureus ; secondary metabolites ; toxins ; ultra-performance liquid chromatography
    Language English
    Dates of publication 2020-09
    Publishing place Elsevier B.V.
    Document type Article
    Note NAL-AP-2-clean
    ZDB-ID 604916-3
    ISSN 1872-8359 ; 0167-7012
    ISSN (online) 1872-8359
    ISSN 0167-7012
    DOI 10.1016/j.mimet.2020.106000
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  7. Article ; Online: The role of siderophores in metal homeostasis of members of the genus Burkholderia.

    Mathew, Anugraha / Jenul, Christian / Carlier, Aurelien L / Eberl, Leo

    Environmental microbiology reports

    2016  Volume 8, Issue 1, Page(s) 103–109

    Abstract: Although members of the genus Burkholderia can utilize a high-affinity iron uptake system to sustain growth under iron-limiting conditions, many strains also produce siderophores, suggesting that they may serve alternative functions. Here we demonstrate ... ...

    Abstract Although members of the genus Burkholderia can utilize a high-affinity iron uptake system to sustain growth under iron-limiting conditions, many strains also produce siderophores, suggesting that they may serve alternative functions. Here we demonstrate that the two Burkholderia siderophores pyochelin and ornibactin can protect the cells from metal toxicity and thus play an alternative role in metal homeostasis. We also demonstrate that metals such as copper and zinc induce the production of ornibactin.
    MeSH term(s) Burkholderia/drug effects ; Burkholderia/metabolism ; Homeostasis ; Metals/metabolism ; Metals/toxicity ; Phenols/metabolism ; Siderophores/metabolism ; Thiazoles/metabolism
    Chemical Substances Metals ; Phenols ; Siderophores ; Thiazoles ; pyochelin (69772-54-9)
    Language English
    Publishing date 2016-02
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1758-2229
    ISSN (online) 1758-2229
    DOI 10.1111/1758-2229.12357
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  8. Article ; Online: Mitigation of

    Sieber, Simon / Mathew, Anugraha / Jenul, Christian / Kohler, Tobias / Bär, Max / Carrión, Víctor J / Cazorla, Francisco M / Stalder, Urs / Hsieh, Ya-Chu / Bigler, Laurent / Eberl, Leo / Gademann, Karl

    Science advances

    2021  Volume 7, Issue 37, Page(s) eabg2293

    Abstract: Pseudomonas ... ...

    Abstract Pseudomonas syringae
    Language English
    Publishing date 2021-09-08
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2810933-8
    ISSN 2375-2548 ; 2375-2548
    ISSN (online) 2375-2548
    ISSN 2375-2548
    DOI 10.1126/sciadv.abg2293
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  9. Article ; Online: The Staphylococcus aureus ArlRS two-component system regulates virulence factor expression through MgrA.

    Crosby, Heidi A / Tiwari, Nitija / Kwiecinski, Jakub M / Xu, Zhen / Dykstra, Allison / Jenul, Christian / Fuentes, Ernesto J / Horswill, Alexander R

    Molecular microbiology

    2019  Volume 113, Issue 1, Page(s) 103–122

    Abstract: The Gram-positive bacterium, Staphylococcus aureus, is a versatile pathogen that can sense and adapt to a wide variety of environments within the human host, in part through its 16 two-component regulatory systems. The ArlRS two-component system has been ...

    Abstract The Gram-positive bacterium, Staphylococcus aureus, is a versatile pathogen that can sense and adapt to a wide variety of environments within the human host, in part through its 16 two-component regulatory systems. The ArlRS two-component system has been shown to affect many cellular processes in S. aureus, including autolysis, biofilm formation, capsule synthesis and virulence. Yet the molecular details of this regulation remained largely unknown. We used RNA sequencing to identify the ArlRS regulon, and found 70% overlap with that of the global regulator MgrA. These genes included cell wall-anchored adhesins (ebh, sdrD), polysaccharide and capsule synthesis genes, cell wall remodeling genes (lytN, ddh), the urease operon, genes involved in metal transport (feoA, mntH, sirA), anaerobic metabolism genes (adhE, pflA, nrdDG) and a large number of virulence factors (lukSF, lukAB, nuc, gehB, norB, chs, scn and esxA). We show that ArlR directly activates expression of mgrA and identify a probable ArlR-binding site (TTTTCTCAT-N
    MeSH term(s) Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; DNA, Bacterial ; Gene Expression Regulation, Bacterial ; Protein Kinases/genetics ; Protein Kinases/metabolism ; Staphylococcus aureus/genetics ; Staphylococcus aureus/metabolism ; Staphylococcus aureus/pathogenicity ; Virulence ; Virulence Factors/genetics ; Virulence Factors/metabolism
    Chemical Substances ArlR protein, Staphylococcus aureus ; Bacterial Proteins ; DNA, Bacterial ; Virulence Factors ; Protein Kinases (EC 2.7.-) ; ArlS protein, Staphylococcus aureus (EC 2.7.3.-)
    Language English
    Publishing date 2019-11-06
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, N.I.H., Intramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 619315-8
    ISSN 1365-2958 ; 0950-382X
    ISSN (online) 1365-2958
    ISSN 0950-382X
    DOI 10.1111/mmi.14404
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  10. Article ; Online: Identification of Extracellular DNA-Binding Proteins in the Biofilm Matrix.

    Kavanaugh, Jeffrey S / Flack, Caralyn E / Lister, Jessica / Ricker, Erica B / Ibberson, Carolyn B / Jenul, Christian / Moormeier, Derek E / Delmain, Elizabeth A / Bayles, Kenneth W / Horswill, Alexander R

    mBio

    2019  Volume 10, Issue 3

    Abstract: We developed a new approach that couples Southwestern blotting and mass spectrometry to discover proteins that bind extracellular DNA (eDNA) in bacterial biofilms. ... ...

    Abstract We developed a new approach that couples Southwestern blotting and mass spectrometry to discover proteins that bind extracellular DNA (eDNA) in bacterial biofilms. Using
    MeSH term(s) Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Biofilms ; Blotting, Southwestern ; DNA, Bacterial/genetics ; DNA-Binding Proteins/genetics ; DNA-Binding Proteins/metabolism ; Extracellular Polymeric Substance Matrix/genetics ; Lipoproteins/genetics ; Lipoproteins/metabolism ; Mass Spectrometry ; Staphylococcus aureus/genetics ; Staphylococcus aureus/physiology ; Static Electricity
    Chemical Substances Bacterial Proteins ; DNA, Bacterial ; DNA-Binding Proteins ; Lipoproteins
    Language English
    Publishing date 2019-06-25
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2557172-2
    ISSN 2150-7511 ; 2161-2129
    ISSN (online) 2150-7511
    ISSN 2161-2129
    DOI 10.1128/mBio.01137-19
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

To top