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Singh S, Kumar S, Dhanasingh I. OVEREXPRESSION, PURIFICATION AND BIOCHEMICAL STUDIES OF SORTASE A FROM Enterococcus faecalis (Ef) AND ITS INHIBITION STUIDES WITH ALOENIN. Acta Trop 2024:107419. [PMID: 39353540 DOI: 10.1016/j.actatropica.2024.107419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2024] [Revised: 09/13/2024] [Accepted: 09/28/2024] [Indexed: 10/04/2024]
Abstract
Sortase A (SrtA) is a bacterial transpeptidase that garnishes the bacterial surface by adding various virulent factors or proteins by cleaving the LPXTG-specific motif between T and G amino acids. These virulence factors assist in the attachment of host cells, which are essential for bacterial virulence. Enterococcus species are among the multidrug-resistant bacteria that cause nosocomial infections; they have drawn a lot of attention recently. SrtA from E. faecalis (Ef) plays a critical role in pathogenesis, making it a suitable target for the development of antibacterial agents. Since SrtA is not involved in bacterial growth and is present on the surface of bacteria, the probability of antibiotic resistance developing is minimal. In this work, we have done cloning, expression and purification of Ef-SrtA using IMAC (Immobilised Metal Affinity Chromatography) followed by Gel filtration chromatography. Purified Ef-SrtA showed maximum activity at pH-8 and temperature between 45-55°C. The fluorescent assay for kinetic studies of Ef-SrtA showed Vmax 3.852 µM.min-1 and kcat 7.7 × 10-2s-1 for the hydrolysis of substrate using Abz-LPETG-K(Dnp)-NH2. We have selected fifteen aloe vera extracted compounds and performed virtual screening and docking experiments to identify potential inhibitors against Ef-SrtA. Among fifteen molecules, Aloenin-a which was bound to the active site with a binding energy of -6.1 kcal/mol, interacted with the active site residues, Arg139, Pro105, Leu39, Ala46, and Cys126. Aloenin-ashowed a significant inhibitory effect against Ef-SrtA, with an IC50 value of 20.68 μM. Aloenin-a inhibits biofilm formation at concentrations of 20-250 µg/mL. The fibrinogen assay showed adherence to fibrinogen was reduced in the presence of Aloenin-a for E. faecalis. The results demonstrated that aloe vera extracts containing Aloenin-a can be a significant antagonist of Ef-SrtA.
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Affiliation(s)
- Suraj Singh
- Centre for Bio-Separation and Technology (CBST), Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India
| | - Sanjit Kumar
- Centre for Bio-Separation and Technology (CBST), Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India; Department of Biotechnology School of Interdisciplinary Education and Research Guru Ghasidas Vishwavidyalaya, Bilaspur, Chhattisgarh, 495009.
| | - Immanuel Dhanasingh
- Centre for Bio-Separation and Technology (CBST), Vellore Institute of Technology, Vellore, 632014, Tamil Nadu, India.
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2
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Jiang F, Cai C, Wang X, Han S. A dual biomarker-targeting probe enables signal-on surface labeling of Staphylococcus aureus. Bioorg Med Chem Lett 2023; 93:129428. [PMID: 37541632 DOI: 10.1016/j.bmcl.2023.129428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 07/13/2023] [Accepted: 07/30/2023] [Indexed: 08/06/2023]
Abstract
Imaging or killing of a specific pathogen is of significance for precise therapy. Staphylococcus aureus (S. aureus) is an infectious gram-positive bacteria relying on Sortase A (SrtA) to anchor cell surface protein on peptidoglycan. We herein report signal-on labeling of S. aureus with self-quenched optical probes featuring vancomycin-conjugated SrtA substrate that is flanked by a dabcyl moiety paired with either fluorescein or eosine photosensizer (PS). SrtA-mediated cleavage of the substrate motif releases the dabcyl quencher, leading to covalent labeling of peptidoglycan with fluorescein or PS of restored photophysical property. The dual biomarked-enabled peptidoglycan labeling enables signal-on imaging and effective photodynamic destruction of S. aureus, suggesting a protheranostic approch activatable to SrtA-positive bacteria engaged in myriad diseases.
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Affiliation(s)
- Feng Jiang
- Department of Chemical Biology, College of Chemistry and Chemical Engineering, the Key Laboratory for Chemical Biology of Fujian Province, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China
| | - Chengteng Cai
- Department of Chemical Biology, College of Chemistry and Chemical Engineering, the Key Laboratory for Chemical Biology of Fujian Province, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China
| | - Xiumin Wang
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361102, China.
| | - Shoufa Han
- Department of Chemical Biology, College of Chemistry and Chemical Engineering, the Key Laboratory for Chemical Biology of Fujian Province, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, China.
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3
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Hansenová Maňásková S, Nazmi K, Van't Hof W, van Belkum A, Kaman WE, Martin NI, Veerman ECI, Bikker FJ. Natural and Synthetic Sortase A Substrates Are Processed by Staphylococcus aureus via Different Pathways. Bioconjug Chem 2022; 33:555-559. [PMID: 35319881 PMCID: PMC9026250 DOI: 10.1021/acs.bioconjchem.2c00012] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
![]()
Endogenous Staphylococcus aureus sortase A (SrtA)
covalently incorporates cell wall anchored proteins equipped with
a SrtA recognition motif (LPXTG) via a lipid II-dependent pathway
into the staphylococcal peptidoglycan layer. Previously, we found
that the endogenous S. aureus SrtA
is able to recognize and process a variety of exogenously added synthetic
SrtA substrates, including K(FITC)LPMTG-amide and K(FITC)-K-vancomycin-LPMTG-amide.
These synthetic substrates are covalently incorporated into the bacterial
peptidoglycan (PG) of S. aureus with
varying efficiencies. In this study, we examined if native and synthetic
substrates are processed by SrtA via the same pathway. Therefore,
the effect of the lipid II inhibiting antibiotic bacitracin on the
incorporation of native and synthetic SrtA substrates was assessed.
Treatment of S. aureus with bacitracin
resulted in a decreased incorporation of protein A in the bacterial
cell wall, whereas incorporation of exogenous synthetic substrates
was increased. These results suggest that natural and exogenous synthetic
substrates are processed by S. aureus via different pathways.
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Affiliation(s)
- Silvie Hansenová Maňásková
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam, 1081 LA Amsterdam, The Netherlands.,Department of Radiotherapy, Erasmus MC Cancer Institute, 3015 CE Rotterdam, The Netherlands
| | - Kamran Nazmi
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam, 1081 LA Amsterdam, The Netherlands
| | - Wim Van't Hof
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam, 1081 LA Amsterdam, The Netherlands
| | | | - Wendy E Kaman
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam, 1081 LA Amsterdam, The Netherlands
| | - Nathaniel I Martin
- Biological Chemistry Group, Institute of Biology Leiden, Leiden University Sylviusweg 72, 2302 BH Leiden, The Netherlands
| | - Enno C I Veerman
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam, 1081 LA Amsterdam, The Netherlands
| | - Floris J Bikker
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam, 1081 LA Amsterdam, The Netherlands
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Kumari P, Bowmik S, Paul SK, Biswas B, Banerjee SK, Murty US, Ravichandiran V, Mohan U. Sortase A: A chemoenzymatic approach for the labeling of cell surfaces. Biotechnol Bioeng 2021; 118:4577-4589. [PMID: 34491580 DOI: 10.1002/bit.27935] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 06/20/2021] [Accepted: 08/27/2021] [Indexed: 01/31/2023]
Abstract
Sortase A, a transpeptidase enzyme is present in many Gram-positive bacteria and helps in the recruitment of the cell surface proteins. Over the last two decades, Sortase A has become an attractive tool for performing in vivo and in vitro ligations. Sortase A-mediated ligation has continuously been used for its specificity, robustness, and highly efficient nature. These properties make it a popular choice among protein engineers as well as researchers from different fields. In this review, we give an overview of Sortase A-mediated ligation of various molecules on the cell surfaces, which can have diverse applications in interdisciplinary fields.
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Affiliation(s)
- Poonam Kumari
- Department of Biotechnology, National Institute of Pharmaceutical Education & Research (NIPER), Guwahati, Assam, India
| | - Sujoy Bowmik
- Department of Biotechnology, National Institute of Pharmaceutical Education & Research (NIPER), Guwahati, Assam, India
| | - Sudipto Kumar Paul
- Department of Biotechnology, National Institute of Pharmaceutical Education & Research (NIPER), Guwahati, Assam, India
| | - Bidisha Biswas
- Department of Biotechnology, National Institute of Pharmaceutical Education & Research (NIPER), Guwahati, Assam, India
| | - Sanjay K Banerjee
- Department of Biotechnology, National Institute of Pharmaceutical Education & Research (NIPER), Guwahati, Assam, India
| | | | - Velayutham Ravichandiran
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education & Research (NIPER), Kolkata, West Bengal, India
| | - Utpal Mohan
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education & Research (NIPER), Kolkata, West Bengal, India
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5
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Artim CM, Kunala M, O'Leary MK, Alabi CA. PEGylated Oligothioetheramide Prodrugs Activated by Host Serum Proteases. Chembiochem 2021; 22:2697-2702. [PMID: 34227209 PMCID: PMC8497000 DOI: 10.1002/cbic.202100146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 07/03/2021] [Indexed: 11/08/2022]
Abstract
Due to the increasing prominence of antibiotic resistance, novel drug discovery and delivery approaches targeting bacteria are essential. In this work we evaluate a prodrug design to improve the cytotoxic profile of polycationic oligothioetheramides (oligoTEAs), which are promising antimicrobials. Herein we chemically modify the oligoTEA, PDT-4G, with a polyethylene glycol (PEG) and show that 1, 2, and 5 kDa PEGs mitigate cytotoxicity. As PEGylation reduces antibacterial activity, we evaluate two peptide linkers which, unlike oligoTEAs, are susceptible to proteolytic cleavage in serum. To gain insight into the prodrug reactivation, two linkers were tested, the 5-residue peptide sequence LMPTG, and the dipeptide sequence VC-PABC. In the presence of 20 % serum, prodrugs made with the VC-PABC linker successfully inhibited bacterial growth. Overall, we observed reactivation of oligoTEAs facilitated by serum protease cleavage of the peptide linkers. This work opens the door to the future design of antimicrobial prodrugs with tunable release profiles.
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Affiliation(s)
- Christine M Artim
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, 120 Olin Hall, Ithaca, NY 14853, USA
| | - Manisha Kunala
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, 120 Olin Hall, Ithaca, NY 14853, USA
| | - Meghan K O'Leary
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, 120 Olin Hall, Ithaca, NY 14853, USA
| | - Christopher A Alabi
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, 120 Olin Hall, Ithaca, NY 14853, USA
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6
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Binzel DW, Li X, Burns N, Khan E, Lee WJ, Chen LC, Ellipilli S, Miles W, Ho YS, Guo P. Thermostability, Tunability, and Tenacity of RNA as Rubbery Anionic Polymeric Materials in Nanotechnology and Nanomedicine-Specific Cancer Targeting with Undetectable Toxicity. Chem Rev 2021; 121:7398-7467. [PMID: 34038115 PMCID: PMC8312718 DOI: 10.1021/acs.chemrev.1c00009] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
RNA nanotechnology is the bottom-up self-assembly of nanometer-scale architectures, resembling LEGOs, composed mainly of RNA. The ideal building material should be (1) versatile and controllable in shape and stoichiometry, (2) spontaneously self-assemble, and (3) thermodynamically, chemically, and enzymatically stable with a long shelf life. RNA building blocks exhibit each of the above. RNA is a polynucleic acid, making it a polymer, and its negative-charge prevents nonspecific binding to negatively charged cell membranes. The thermostability makes it suitable for logic gates, resistive memory, sensor set-ups, and NEM devices. RNA can be designed and manipulated with a level of simplicity of DNA while displaying versatile structure and enzyme activity of proteins. RNA can fold into single-stranded loops or bulges to serve as mounting dovetails for intermolecular or domain interactions without external linking dowels. RNA nanoparticles display rubber- and amoeba-like properties and are stretchable and shrinkable through multiple repeats, leading to enhanced tumor targeting and fast renal excretion to reduce toxicities. It was predicted in 2014 that RNA would be the third milestone in pharmaceutical drug development. The recent approval of several RNA drugs and COVID-19 mRNA vaccines by FDA suggests that this milestone is being realized. Here, we review the unique properties of RNA nanotechnology, summarize its recent advancements, describe its distinct attributes inside or outside the body and discuss potential applications in nanotechnology, medicine, and material science.
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Affiliation(s)
- Daniel W Binzel
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Xin Li
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Nicolas Burns
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Eshan Khan
- Department of Cancer Biology and Genetics, The Ohio State University Comprehensive Cancer Center, College of Medicine, Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, United States
| | - Wen-Jui Lee
- TMU Research Center of Cancer Translational Medicine, School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Department of Laboratory Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan
| | - Li-Ching Chen
- TMU Research Center of Cancer Translational Medicine, School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Department of Laboratory Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan
| | - Satheesh Ellipilli
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Wayne Miles
- Department of Cancer Biology and Genetics, The Ohio State University Comprehensive Cancer Center, College of Medicine, Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, United States
| | - Yuan Soon Ho
- TMU Research Center of Cancer Translational Medicine, School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Department of Laboratory Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan
| | - Peixuan Guo
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
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7
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Park J, Lee S, Kim Y, Yoo TH. Methods to generate site-specific conjugates of antibody and protein. Bioorg Med Chem 2021; 30:115946. [DOI: 10.1016/j.bmc.2020.115946] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 12/07/2020] [Accepted: 12/09/2020] [Indexed: 02/07/2023]
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8
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Kumari P, Nath Y, Murty US, Ravichandiran V, Mohan U. Sortase A Mediated Bioconjugation of Common Epitopes Decreases Biofilm Formation in Staphylococcus aureus. Front Microbiol 2020; 11:1702. [PMID: 32903711 PMCID: PMC7438799 DOI: 10.3389/fmicb.2020.01702] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 06/29/2020] [Indexed: 11/13/2022] Open
Abstract
Staphylococcus aureus is one of the most notorious pathogens and is frequently associated with nosocomial infections imposing serious risk to immune-compromised patients. This is in part due to its ability to colonize at the surface of indwelling medical devices and biofilm formation. Combating the biofilm formation with antibiotics has its own challenges like higher values of minimum inhibitory concentrations. Here, we describe a new approach to target biofilm formation by Gram positive bacteria. Sortase A is a transpeptidase enzyme which is responsible for tagging of around ∼22 cell surface proteins onto the outer surface. These proteins play a major role in the bacterial virulence. Sortase A recognizes its substrate through LPXTG motif. Here, we use this approach to install the synthetic peptide substrates onS. aureus. Sortase A substrate mimic, 6His-LPETG peptide was synthesized using solid phase peptide chemistry. Incorporation of the peptide on the cell surface was measured using ELISA. Effect of peptide incubation on Staphylococcus aureus biofilm was also studied. 71.1% biofilm inhibition was observed with 100 μM peptide while on silicon coated rubber latex catheter, 45.82% inhibition was observed. The present work demonstrates the inability of surface modified S. aureus to establish biofilm formation thereby presenting a novel method for attenuating its virulence.
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Affiliation(s)
- Poonam Kumari
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research, Guwahati, India
| | - Yutika Nath
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research, Guwahati, India
| | | | - Velayutham Ravichandiran
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Kolkata, India
| | - Utpal Mohan
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Kolkata, India
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9
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Barthels F, Marincola G, Marciniak T, Konhäuser M, Hammerschmidt S, Bierlmeier J, Distler U, Wich PR, Tenzer S, Schwarzer D, Ziebuhr W, Schirmeister T. Asymmetric Disulfanylbenzamides as Irreversible and Selective Inhibitors of Staphylococcus aureus Sortase A. ChemMedChem 2020; 15:839-850. [PMID: 32118357 PMCID: PMC7318353 DOI: 10.1002/cmdc.201900687] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 02/07/2020] [Indexed: 12/19/2022]
Abstract
Staphylococcus aureus is one of the most frequent causes of nosocomial and community-acquired infections, with drug-resistant strains being responsible for tens of thousands of deaths per year. S. aureus sortase A inhibitors are designed to interfere with virulence determinants. We have identified disulfanylbenzamides as a new class of potent inhibitors against sortase A that act by covalent modification of the active-site cysteine. A broad series of derivatives were synthesized to derive structure-activity relationships (SAR). In vitro and in silico methods allowed the experimentally observed binding affinities and selectivities to be rationalized. The most active compounds were found to have single-digit micromolar Ki values and caused up to a 66 % reduction of S. aureus fibrinogen attachment at an effective inhibitor concentration of 10 μM. This new molecule class exhibited minimal cytotoxicity, low bacterial growth inhibition and impaired sortase-mediated adherence of S. aureus cells.
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Affiliation(s)
- Fabian Barthels
- Institute for Pharmacy and BiochemistryJohannes-Gutenberg-University of MainzStaudinger Weg 555128MainzGermany
| | - Gabriella Marincola
- Institute for Molecular Infection BiologyJulius-Maximilians-University of WürzburgJosef-Schneider-Strasse 297080WürzburgGermany
| | - Tessa Marciniak
- Institute for Molecular Infection BiologyJulius-Maximilians-University of WürzburgJosef-Schneider-Strasse 297080WürzburgGermany
| | - Matthias Konhäuser
- Institute for Pharmacy and BiochemistryJohannes-Gutenberg-University of MainzStaudinger Weg 555128MainzGermany
| | - Stefan Hammerschmidt
- Institute for Pharmacy and BiochemistryJohannes-Gutenberg-University of MainzStaudinger Weg 555128MainzGermany
| | - Jan Bierlmeier
- Interfaculty Institute of BiochemistryEberhard-Karls-University of TübingenHoppe-Seyler-Strasse 472076TübingenGermany
| | - Ute Distler
- Institute for ImmunologyUniversity Medical CenterJohannes-Gutenberg-University of MainzLangenbeckstr. 155131MainzGermany
- Focus Program Translational Neuroscience (FTN)University Medical CenterLangenbeckstr. 155131MainzGermany
| | - Peter R. Wich
- Institute for Pharmacy and BiochemistryJohannes-Gutenberg-University of MainzStaudinger Weg 555128MainzGermany
- School of Chemical EngineeringUniversity of New South WalesScience and Engineering BuildingSydneyNSW 2052Australia
| | - Stefan Tenzer
- Institute for ImmunologyUniversity Medical CenterJohannes-Gutenberg-University of MainzLangenbeckstr. 155131MainzGermany
| | - Dirk Schwarzer
- Interfaculty Institute of BiochemistryEberhard-Karls-University of TübingenHoppe-Seyler-Strasse 472076TübingenGermany
| | - Wilma Ziebuhr
- Institute for Molecular Infection BiologyJulius-Maximilians-University of WürzburgJosef-Schneider-Strasse 297080WürzburgGermany
| | - Tanja Schirmeister
- Institute for Pharmacy and BiochemistryJohannes-Gutenberg-University of MainzStaudinger Weg 555128MainzGermany
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Sabulski MJ, Pidgeon SE, Pires MM. Immuno-targeting of Staphylococcus aureus via surface remodeling complexes. Chem Sci 2017; 8:6804-6809. [PMID: 29147504 PMCID: PMC5643955 DOI: 10.1039/c7sc02721d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 08/20/2017] [Indexed: 12/28/2022] Open
Abstract
Agents with novel mechanisms of action are needed to complement traditional antibiotics. Towards these goals, we have exploited the surface-homing properties of vancomycin to tag the surface of Gram-positive pathogens with immune cell attractants in two unique modes. First, vancomycin was conjugated to the small molecule hapten 2,4-dinitrophenol (DNP) to promote bacterial opsonization. Second, we built on these results by improving the tagging specificity and mechanism of incorporation by coupling it to a sortase A substrate peptide. We demonstrated, for the first time, that the surface of Staphylococcus aureus (S. aureus) can be metabolically labeled in live Caenorhabditis elegans hosts. These constructs represent a class of promising narrow-spectrum agents that target S. aureus for opsonization and establish a new surface labeling modality in live host organisms, which should be a powerful tool in dissecting features of host-pathogen interactions.
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Affiliation(s)
- Mary J Sabulski
- Department of Chemistry , Lehigh University , 6 E Packer Ave. , Bethlehem , PA 18015 , USA .
| | - Sean E Pidgeon
- Department of Chemistry , Lehigh University , 6 E Packer Ave. , Bethlehem , PA 18015 , USA .
| | - Marcos M Pires
- Department of Chemistry , Lehigh University , 6 E Packer Ave. , Bethlehem , PA 18015 , USA .
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11
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Streptococcus suis sortase A is Ca2+ independent and is inhibited by acteoside, isoquercitrin and baicalin. PLoS One 2017; 12:e0173767. [PMID: 28319184 PMCID: PMC5358767 DOI: 10.1371/journal.pone.0173767] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 02/27/2017] [Indexed: 11/30/2022] Open
Abstract
Sortase A (SrtA) has long been recognized as an ideal drug target for therapeutic agents against Gram-positive pathogens. However, the SrtA of Streptococcus suis (Ss-SrtA), an important zoonotic agent, has not been studied. In this study, the enzymatic properties of Ss-SrtA were investigated, and inhibition of Ss-SrtA by natural products was evaluated. Ss-SrtA was expressed and purified. The purified recombinant Ss-SrtA had maximal activity at pH 6.0–7.5, 45°C, and showed a Km of 6.7 μM for the hydrolysis of substrate abz-LPATG-dnp. Different from Staphylococcus aureus SrtA (Sa-SrtA) which is stimulated by Ca2+, Ss-SrtA was observed to be Ca2+ independent. Structural analysis showed that salt bridges formed between K111 and D180 in Ss-SrtA replaced the function of Ca2+ in Sa-SrtA to stabilize the substrate-binding cleft. Site-directed mutagenesis identified H126, C192 and R200 as the key residues of Ss-SrtA active site. To discover potential inhibitors, the percent inhibition of sortase activity by natural products was measured. Among these selected natural products, acteoside, isoquercitrin and baicalin were discovered as novel SrtA inhibitors, with IC50 values of 36.3 ± 1.3 μM, 100.0 ± 1.3 μM and 85.4 ± 1.5 μM, respectively. The inhibitory effects of these three natural products were further confirmed on endogenous Sa-SrtA. Using a previously established S. aureus model with a fluorescent-labeled Sa-SrtA substrate, acteoside, isoquercitrin, and baicalin showed 86%, 28% and 45% inhibition on endogenous Sa-SrtA activity, respectively. Overall, these findings shed new light on enzymatic properties, Ca2+-independent catalytic mechanism and potential inhibitors of Ss-SrtA.
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12
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Staphylococcus epidermidis ΔSortase A strain elicits protective immunity against Staphylococcus aureus infection. Antonie van Leeuwenhoek 2016; 110:133-143. [PMID: 27757703 DOI: 10.1007/s10482-016-0784-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 10/06/2016] [Indexed: 10/20/2022]
Abstract
Staphylococcus aureus and Staphylococcus epidermidis are two of the most significant opportunistic human pathogens, causing medical implant and nosocomial infections worldwide. These bacteria contain surface proteins that play crucial roles in multiple biological processes. It has become apparent that they have evolved a number of unique mechanisms by which they can immobilise proteins on their surface. Notably, a conserved cell membrane-anchored enzyme, sortase A (SrtA), can catalyse the covalent attachment of precursor bacterial cell wall-attached proteins to peptidoglycan. Considering its indispensable role in anchoring substrates to the cell wall and its effects on virulence, SrtA has attracted great attention. In this study, a 549-bp gene was cloned from a pathogenic S. epidermidis strain, YC-1, which shared high identity with srtA from other Staphylococcus spp. A mutant strain, YC-1ΔsrtA, was then constructed by allelic exchange mutagenesis. The direct survival rate assay suggested that YC-1ΔsrtA had a lower survival capacity in healthy mice blood compare with the wild-type strain, indicating that the deletion of srtA affects the virulence and infectious capacity of S. epidermidis YC-1. YC-1ΔsrtA was then administered via intraperitoneal injection and it provided a relative percent survival value of 72.7 % in mice against S. aureus TC-1 challenge. These findings demonstrate the possbility that YC-1ΔsrtA might be used as a live attenuated vaccine to produce cross-protection against S. aureus.
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Hansenová Maňásková S, Bikker FJ, Nazmi K, van Zuidam R, Slotman JA, van Cappellen WA, Houtsmuller AB, Veerman ECI, Kaman WE. Incorporation of a Valine-Leucine-Lysine-Containing Substrate in the Bacterial Cell Wall. Bioconjug Chem 2016; 27:2418-2423. [PMID: 27611478 DOI: 10.1021/acs.bioconjchem.6b00381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The emergence of antibiotic-resistant bacteria is a major public health threat, and therefore novel antimicrobial targets and strategies are urgently needed. In this regard, cell-wall-associated proteases are envisaged as interesting antimicrobial targets due to their role in cell wall remodeling. Here, we describe the discovery and characteristics of a protease substrate that is processed by a bacterial cell-wall-associated protease. Stationary-phase grown Gram-positive bacteria were incubated with fluorogenic protease substrates, and their cleavage and covalent incorporation into the cell wall was analyzed. Of all of the substrates used, only one substrate, containing a valine-leucine-lysine (VLK) motif, was covalently incorporated into the bacterial cell wall. Linkage of the VLK-peptide substrate appeared unrelated to sortase A and B activity, as both wild-type and sortase A and B knock out Staphylococcus aureus strains incorporated this substrate into their cell wall with comparable efficiency. Additionally, the VLK-peptide substrate showed significantly higher incorporation in the cell wall of VanA-positive Enterococcus faecium strains than in VanB- and vancomycin-susceptible isolates. In conclusion, the VLK-peptide substrate identified in this study shows promise as a vehicle for targeting antimicrobial compounds and diagnostic contrast agents to the bacterial cell wall.
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Affiliation(s)
- Silvie Hansenová Maňásková
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC , Wytemaweg 80, 3015 CE Rotterdam, The Netherlands.,Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam , Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands
| | - Floris J Bikker
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam , Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands
| | - Kamran Nazmi
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam , Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands
| | - Rianne van Zuidam
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC , Wytemaweg 80, 3015 CE Rotterdam, The Netherlands
| | - Johan A Slotman
- Optical Imaging Center, Department of Pathology, Josephine Nefkens Institute, Erasmus MC , Dr Molewaterplein 50, Rotterdam 3015 GE, The Netherlands
| | - Wiggert A van Cappellen
- Optical Imaging Center, Department of Pathology, Josephine Nefkens Institute, Erasmus MC , Dr Molewaterplein 50, Rotterdam 3015 GE, The Netherlands
| | - Adriaan B Houtsmuller
- Optical Imaging Center, Department of Pathology, Josephine Nefkens Institute, Erasmus MC , Dr Molewaterplein 50, Rotterdam 3015 GE, The Netherlands
| | - Enno C I Veerman
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam , Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands
| | - Wendy E Kaman
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC , Wytemaweg 80, 3015 CE Rotterdam, The Netherlands.,Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam , Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands
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