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Hintzen JCJ, Abujubara H, Tietze D, Tietze AA. The Complete Assessment of Small Molecule and Peptidomimetic Inhibitors of Sortase A Towards Antivirulence Treatment. Chemistry 2024; 30:e202401103. [PMID: 38716707 DOI: 10.1002/chem.202401103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Indexed: 06/20/2024]
Abstract
This review covers the most recent advances in the development of inhibitors for the bacterial enzyme sortase A (SrtA). Sortase A (SrtA) is a critical virulence factor, present ubiquitously in Gram-positive bacteria of which many are pathogenic. Sortases are key enzymes regulating bacterial adherence to host cells, by anchoring extracellular matrix-binding proteins to the bacterial outer cell wall. By targeting virulence factors, effective treatment can be achieved, without inducing antibiotic resistance to the treatment. This is a potentially more sustainable, long-term approach to treating bacterial infections, including ones that display multiple resistance to current therapeutics. There are many promising approaches available for SrtA inhibition, some of which have the potential to advance into further clinical development, with peptidomimetic and in vivo active small molecules being among the most promising. There are currently no approved drugs on the market targeting SrtA, despite its promise, adding to the relevance of this review article, as it extends to the pharmaceutical industry additionally to academic researchers.
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Affiliation(s)
- Jordi C J Hintzen
- University of Gothenburg, Department of Chemistry and Molecular Biology, Wallenberg Centre for Molecular and Translational Medicine, Kemigården 4, 412 96, Göteborg, Sweden
| | - Helal Abujubara
- University of Gothenburg, Department of Chemistry and Molecular Biology, Wallenberg Centre for Molecular and Translational Medicine, Kemigården 4, 412 96, Göteborg, Sweden
| | - Daniel Tietze
- University of Gothenburg, Department of Chemistry and Molecular Biology, Wallenberg Centre for Molecular and Translational Medicine, Kemigården 4, 412 96, Göteborg, Sweden
| | - Alesia A Tietze
- University of Gothenburg, Department of Chemistry and Molecular Biology, Wallenberg Centre for Molecular and Translational Medicine, Kemigården 4, 412 96, Göteborg, Sweden
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2
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Amacher JF, Antos JM. Sortases: structure, mechanism, and implications for protein engineering. Trends Biochem Sci 2024; 49:596-610. [PMID: 38692993 DOI: 10.1016/j.tibs.2024.04.003] [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: 11/06/2023] [Revised: 03/22/2024] [Accepted: 04/15/2024] [Indexed: 05/03/2024]
Abstract
Sortase enzymes are critical cysteine transpeptidases on the surface of bacteria that attach proteins to the cell wall and are involved in the construction of bacterial pili. Due to their ability to recognize specific substrates and covalently ligate a range of reaction partners, sortases are widely used in protein engineering applications via sortase-mediated ligation (SML) strategies. In this review, we discuss recent structural studies elucidating key aspects of sortase specificity and the catalytic mechanism. We also highlight select recent applications of SML, including examples where fundamental studies of sortase structure and function have informed the continued development of these enzymes as tools for protein engineering.
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Affiliation(s)
- Jeanine F Amacher
- Department of Chemistry, Western Washington University, Bellingham, WA 98225, USA.
| | - John M Antos
- Department of Chemistry, Western Washington University, Bellingham, WA 98225, USA.
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3
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Vogel BA, Blount JM, Kodama HM, Goodwin-Rice NJ, Andaluz DJ, Jackson SN, Antos JM, Amacher JF. A unique binding mode of P1' Leu-containing target sequences for Streptococcus pyogenes sortase A results in alternative cleavage. RSC Chem Biol 2024; 5:30-40. [PMID: 38179192 PMCID: PMC10763551 DOI: 10.1039/d3cb00129f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Accepted: 09/26/2023] [Indexed: 01/06/2024] Open
Abstract
Sortase enzymes are cysteine transpeptidases that attach environmental sensors, toxins, and other proteins to the cell surface in Gram-positive bacteria. The recognition motif for many sortases is the cell wall sorting signal (CWSS), LPXTG, where X = any amino acid. Recent work from ourselves and others has described recognition of additional amino acids at a number of positions in the CWSS, specifically at the Thr (or P1) and Gly (or P1') positions. In addition, although standard cleavage occurs between these two residues (P1/P1'), we previously observed that the SrtA enzyme from Streptococcus pneumoniae will cleave after the P1' position when its identity is a Leu or Phe. The stereochemical basis of this alternative cleavage is not known, although homologs, e.g., SrtA from Listeria monocytogenes or Staphylococcus aureus do not show alternative cleavage to a significant extent. Here, we use protein biochemistry, structural biology, and computational biochemistry to predict an alternative binding mode that facilitates alternative cleavage. We use Streptococcus pyogenes SrtA (spySrtA) as our model enzyme, first confirming that it shows similar standard/alternative cleavage ratios for LPATL, LPATF, and LPATY sequences. Molecular dynamics simulations suggest that when P1' is Leu, this amino acid binds in the canonical S1 pocket, pushing the P1 Thr towards solvent. The P4 Leu (L̲PATL) binds as it does in standard binding, resulting in a puckered binding conformation. We use P1 Glu-containing peptides to support our hypotheses, and present the complex structure of spySrtA-LPALA to confirm favorable accommodation of Leu in the S1 pocket. Overall, we structurally characterize an alternative binding mode for spySrtA and specific target sequences, expanding the potential protein engineering possibilities in sortase-mediated ligation applications.
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Affiliation(s)
- Brandon A Vogel
- Department of Chemistry, Western Washington University, 516 High St - MS9150 Bellingham WA 98225 USA +1-360-650-2826 +1-360-650-2271 +1-360-650-4397
| | - Jadon M Blount
- Department of Chemistry, Western Washington University, 516 High St - MS9150 Bellingham WA 98225 USA +1-360-650-2826 +1-360-650-2271 +1-360-650-4397
| | - Hanna M Kodama
- Department of Chemistry, Western Washington University, 516 High St - MS9150 Bellingham WA 98225 USA +1-360-650-2826 +1-360-650-2271 +1-360-650-4397
| | - Noah J Goodwin-Rice
- Department of Chemistry, Western Washington University, 516 High St - MS9150 Bellingham WA 98225 USA +1-360-650-2826 +1-360-650-2271 +1-360-650-4397
| | - Devin J Andaluz
- Department of Chemistry, Western Washington University, 516 High St - MS9150 Bellingham WA 98225 USA +1-360-650-2826 +1-360-650-2271 +1-360-650-4397
| | - Sophie N Jackson
- Department of Chemistry, Western Washington University, 516 High St - MS9150 Bellingham WA 98225 USA +1-360-650-2826 +1-360-650-2271 +1-360-650-4397
| | - John M Antos
- Department of Chemistry, Western Washington University, 516 High St - MS9150 Bellingham WA 98225 USA +1-360-650-2826 +1-360-650-2271 +1-360-650-4397
| | - Jeanine F Amacher
- Department of Chemistry, Western Washington University, 516 High St - MS9150 Bellingham WA 98225 USA +1-360-650-2826 +1-360-650-2271 +1-360-650-4397
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4
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Godse S, Sapar T, Amacher JF. An idea to explore: Engaging high school students in structure-function studies of bacterial sortase enzymes and inhibitors - A comprehensive computational experimental pipeline. BIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION : A BIMONTHLY PUBLICATION OF THE INTERNATIONAL UNION OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2023; 51:606-615. [PMID: 37462254 DOI: 10.1002/bmb.21769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 06/20/2023] [Accepted: 07/05/2023] [Indexed: 11/22/2023]
Abstract
High school science fairs provide an exceptional opportunity for students to gain experience with scientific research, and participation has positive outcomes with respect to chosen careers in the sciences. However, it can be challenging to engage high school students in university-level research outside of formal internship programs. Here, we describe an experimental pipeline for a computational structural biology project that engages high school students. Students are involved at every step of the investigation and utilize freely available software to dock inhibitors onto protein homologues, and then analyze the resulting complexes. Bacterial sortases are transpeptidases on the cell surface of Gram-positive bacteria and are a potential target for the development of antibiotics. Students modeled inhibitors bound to sortases from several organisms, asking questions about affinity and selectivity. Their project was ranked in the top 10% at both regional and state science fairs. This project design is easily adaptable to countless other protein systems and provides a pipeline for collaborative high school student/university professor inquiry.
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Affiliation(s)
| | - Tanvi Sapar
- Tesla STEM High School, Redmond, Washington, USA
| | - Jeanine F Amacher
- Department of Chemistry, Western Washington University, Bellingham, Washington, USA
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5
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Liu M, Lv Q, Xu J, Liu B, Zhou Y, Zhang S, Shen X, Wang L. Isoflavone glucoside genistin, an inhibitor targeting Sortase A and Listeriolysin O, attenuates the virulence of Listeria monocytogenes in vivo and in vitro. Biochem Pharmacol 2023; 209:115447. [PMID: 36746262 DOI: 10.1016/j.bcp.2023.115447] [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: 08/24/2022] [Revised: 01/30/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023]
Abstract
As a common intracellular facultative anaerobic Gram-positive bacterium, Listeria monocytogenes (L. monocytogenes) exhibits strong resistance to extreme environments, such as low temperature and a wide range of pH values, causing contamination in food production and processing. Sortase A (SrtA) and listeriolysin O (LLO), two crucial virulence factors of L. monocytogenes, are widely recognized as potential targets for the development of anti-L. monocytogenes infection drugs. In this study, we found that genistin simultaneously inhibits the peptidase activity of SrtA and the hemolytic activity of LLO without affecting the growth of L. monocytogenes, alleviating concerns about developing resistance. Furthermore, we demonstrated that genistin reduces L. monocytogenes biofilm formation and invasion of human colorectal cancer (Caco-2) cells. Subsequent mechanistic studies revealed that genistin inhibited LLO-mediated Caco-2 cell damage by blocking LLO oligomerization. Fluorescence quenching assay revealed the potential binding mode of SrtA and LLO to genistin. Genistin might bind to the active pocket of SrtA through residues Leu33, Asn29, and Met40, interacting with D1 domain of LLO involved in oligomerization and pore formation through residues Asn259. Studies in infection models revealed that genistin reduces mortality and pathological damage in mice infected with L. monocytogenes. These results indicate that genistin is a promising anti-virulence agent that could be considered an alternative candidate for the treatment of L. monocytogenes infection.
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Affiliation(s)
- Minda Liu
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China; Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, China
| | - Qianghua Lv
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China; Shandong Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, P.R.China; Key Laboratory of Livestock and Poultry Multi-omics of MARA, P.R.China
| | - Jingwen Xu
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Baichen Liu
- The Second Bethune Clinical Medical College of Jilin University, Changchun 130012, Jilin, People's Republic of China
| | - Yonglin Zhou
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China; Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, China
| | - Siqi Zhang
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China; Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, China
| | - Xue Shen
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China; Department of Food Science, College of Food Science and Engineering, Jilin University, Changchun, China.
| | - Lin Wang
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China; Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, China.
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6
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Guo L, Yin X, Liu Q. Fecal microbiota transplantation reduces mouse mortality from Listeria monocytogenes infection. Microb Pathog 2023; 178:106036. [PMID: 36813004 DOI: 10.1016/j.micpath.2023.106036] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/16/2023] [Accepted: 02/20/2023] [Indexed: 02/23/2023]
Abstract
Listeria monocytogenes (Lm) is a food bacterium with strong pathogenicity which causes infections via the gastrointestinal tract. Mechanisms by which gut microbiota (GM) resist microbial infections have received little attention. Eight-week-old mice were orally inoculated with wild-type Lm EGD-e and fecal microbiota transplantation (FMT) employed. GM richness and diversity of infected mice changed rapidly within 24h. Firmicutes class decreased and Bacteroidetes, Tenericutes and Ruminococcaceae increased significantly. Coprococcus, Blautia and Eubacterium also increased on the 3rd day post-infection. Moreover, GM transplanted from healthy mice reduced mortality of infected mice by approximately 32%. FMT treatment decreased production of TNFα, IFN-γ, IL-1β and IL-6 relative to PBS treatment. In summary, FMT has potential as a treatment against Lm infection and may be used for bacterial resistance management. Further work is required to elucidate the key GM effector molecules.
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Affiliation(s)
- Liang Guo
- Zaozhuang University, Shandong, 277160, China; School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China
| | | | - Qing Liu
- School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China.
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In Vivo Safety and Efficacy of Chalcone-Loaded Microparticles with Modified Polymeric Matrix against Cutaneous Leishmaniasis. Pharmaceutics 2022; 15:pharmaceutics15010051. [PMID: 36678680 PMCID: PMC9864040 DOI: 10.3390/pharmaceutics15010051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 12/16/2022] [Accepted: 12/20/2022] [Indexed: 12/28/2022] Open
Abstract
Current chemotherapy of cutaneous leishmaniasis (CL) is based on repeated systemic or intralesional administration of drugs that often cause severe toxicity. Previously, we demonstrated the therapeutic potential of biodegradable poly(lactic-co-glycolic acid) (PLGA) microparticles (MPs) loaded with 8% of the nitrochalcone CH8 (CH8/PLGA) prepared by a conventional bench method. Aiming at an industrially scalable process and increased drug loading, new MPs were prepared by spray drying: CH8/PDE with PLGA matrix and CH8/PVDE with PLGA + polyvinylpyrrolidone (PVP) matrix, both with narrower size distribution and higher drug loading (18%) than CH8/PLGA. Animal studies were conducted to evaluate their clinical feasibility. Both MP types induced transient local swelling and inflammation, peaking at 1−2 days, following a single intralesional injection. Different from CH8/PDE that released 90% of the drug in the ear tissue in 60 days, CH8/PVDE achieved that in 30 days. The therapeutic efficacy of a single intralesional injection was evaluated in BALB/c mice infected with Leishmania (Leishmania) amazonensis and golden hamsters infected with L. (Viannia) braziliensis. CH8/PVDE promoted greater reduction in parasite burden than CH8/PDE or CH8/PLGA, measured at one month and two months after the treatment. Thus, addition of PVP to PLGA MP matrix accelerates drug release in vivo and increases its therapeutic effect against CL.
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8
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Gao M, Johnson DA, Piper IM, Kodama HM, Svendsen JE, Tahti E, Longshore‐Neate F, Vogel B, Antos JM, Amacher JF. Structural and biochemical analyses of selectivity determinants in chimeric Streptococcus Class A sortase enzymes. Protein Sci 2022; 31:701-715. [PMID: 34939250 PMCID: PMC8862441 DOI: 10.1002/pro.4266] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 01/22/2023]
Abstract
Sequence variation in related proteins is an important characteristic that modulates activity and selectivity. An example of a protein family with a large degree of sequence variation is that of bacterial sortases, which are cysteine transpeptidases on the surface of gram-positive bacteria. Class A sortases are responsible for attachment of diverse proteins to the cell wall to facilitate environmental adaption and interaction. These enzymes are also used in protein engineering applications for sortase-mediated ligations (SML) or sortagging of protein targets. We previously investigated SrtA from Streptococcus pneumoniae, identifying a number of putative β7-β8 loop-mediated interactions that affected in vitro enzyme function. We identified residues that contributed to the ability of S. pneumoniae SrtA to recognize several amino acids at the P1' position of the substrate motif, underlined in LPXTG, in contrast to the strict P1' Gly recognition of SrtA from Staphylococcus aureus. However, motivated by the lack of a structural model for the active, monomeric form of S. pneumoniae SrtA, here, we expanded our studies to other Streptococcus SrtA proteins. We solved the first monomeric structure of S. agalactiae SrtA which includes the C-terminus, and three others of β7-β8 loop chimeras from S. pyogenes and S. agalactiae SrtA. These structures and accompanying biochemical data support our previously identified β7-β8 loop-mediated interactions and provide additional insight into their role in Class A sortase substrate selectivity. A greater understanding of individual SrtA sequence and structural determinants of target selectivity may also facilitate the design or discovery of improved sortagging tools.
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Affiliation(s)
- Melody Gao
- Department of ChemistryWestern Washington UniversityBellinghamWashingtonUSA
| | - D. Alex Johnson
- Department of ChemistryWestern Washington UniversityBellinghamWashingtonUSA
| | - Isabel M. Piper
- Department of ChemistryWestern Washington UniversityBellinghamWashingtonUSA
| | - Hanna M. Kodama
- Department of ChemistryWestern Washington UniversityBellinghamWashingtonUSA
| | - Justin E. Svendsen
- Department of ChemistryWestern Washington UniversityBellinghamWashingtonUSA
| | - Elise Tahti
- Department of ChemistryWestern Washington UniversityBellinghamWashingtonUSA
| | | | - Brandon Vogel
- Department of ChemistryWestern Washington UniversityBellinghamWashingtonUSA
| | - John M. Antos
- Department of ChemistryWestern Washington UniversityBellinghamWashingtonUSA
| | - Jeanine F. Amacher
- Department of ChemistryWestern Washington UniversityBellinghamWashingtonUSA
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9
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Guan XN, Zhang T, Yang T, Dong Z, Yang S, Lan L, Gan J, Yang CG. Covalent sortase A inhibitor ML346 prevents Staphylococcus aureus infection of Galleria mellonella. RSC Med Chem 2022; 13:138-149. [PMID: 35308030 PMCID: PMC8864484 DOI: 10.1039/d1md00316j] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 10/31/2021] [Indexed: 12/16/2023] Open
Abstract
The housekeeping sortase A (SrtA), a membrane-associated cysteine transpeptidase, is responsible for anchoring surface proteins to the cell wall peptidoglycan in Gram-positive bacteria. This process is essential for the regulation of bacterial virulence and pathogenicity. Therefore, SrtA is considered to be an ideal target for antivirulence therapy. In this study, we report that ML346, a compound with a barbituric acid and cinnamaldehyde scaffold, functions as an irreversible inhibitor of Staphylococcus aureus SrtA (SaSrtA) and Streptococcus pyogenes SrtA (SpSrtA) in vitro at low micromolar concentrations. According to our X-ray crystal structure of the SpSrtAΔN81/ML346 complex (Protein Data Bank ID: 7V6K), ML346 covalently modifies the thiol group of Cys208 in the active site of SpSrtA. Importantly, ML346 significantly attenuated the virulence phenotypes of S. aureus and exhibited inhibitory effects on Galleria mellonella larva infection caused by S. aureus. Collectively, our results indicate that ML346 has potential for development as a covalent antivirulence agent for treating S. aureus infections, including methicillin-resistant S. aureus.
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Affiliation(s)
- Xiang-Na Guan
- Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences Shanghai 201203 China
- University of the Chinese Academy of Sciences Beijing 100049 China
| | - Tao Zhang
- Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences Shanghai 201203 China
| | - Teng Yang
- Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences Shanghai 201203 China
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals, Guizhou University Guiyang 550025 China
| | - Ze Dong
- Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences Shanghai 201203 China
| | - Song Yang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals, Guizhou University Guiyang 550025 China
| | - Lefu Lan
- Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences Shanghai 201203 China
- University of the Chinese Academy of Sciences Beijing 100049 China
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences Hangzhou 310024 China
| | - Jianhua Gan
- School of Life Sciences, Fudan University Shanghai 200433 China
| | - Cai-Guang Yang
- Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences Shanghai 201203 China
- University of the Chinese Academy of Sciences Beijing 100049 China
- School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences Hangzhou 310024 China
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10
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Janež N, Škrlj B, Sterniša M, Klančnik A, Sabotič J. The role of the Listeria monocytogenes surfactome in biofilm formation. Microb Biotechnol 2021; 14:1269-1281. [PMID: 34106516 PMCID: PMC8313260 DOI: 10.1111/1751-7915.13847] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 05/12/2021] [Accepted: 05/17/2021] [Indexed: 12/11/2022] Open
Abstract
Listeria monocytogenes is a highly pathogenic foodborne bacterium that is ubiquitous in the natural environment and capable of forming persistent biofilms in food processing environments. This species has a rich repertoire of surface structures that enable it to survive, adapt and persist in various environments and promote biofilm formation. We review current understanding and advances on how L. monocytogenes organizes its surface for biofilm formation on surfaces associated with food processing settings, because they may be an important target for development of novel antibiofilm compounds. A synthesis of the current knowledge on the role of Listeria surfactome, comprising peptidoglycan, teichoic acids and cell wall proteins, during biofilm formation on abiotic surfaces is provided. We consider indications gained from genome-wide studies and discuss surfactome structures with established mechanistic aspects in biofilm formation. Additionally, we look at the analogies to the species L. innocua, which is closely related to L. monocytogenes and often used as its model (surrogate) organism.
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Affiliation(s)
- Nika Janež
- Department of BiotechnologyJožef Stefan InstituteLjubljanaSlovenia
| | - Blaž Škrlj
- Department of Knowledge TechnologiesJožef Stefan InstituteLjubljanaSlovenia
- Jožef Stefan International Postgraduate SchoolLjubljanaSlovenia
| | - Meta Sterniša
- Department of Food Science and TechnologyBiotechnical FacultyUniversity of LjubljanaLjubljanaSlovenia
| | - Anja Klančnik
- Department of Food Science and TechnologyBiotechnical FacultyUniversity of LjubljanaLjubljanaSlovenia
| | - Jerica Sabotič
- Department of BiotechnologyJožef Stefan InstituteLjubljanaSlovenia
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11
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Wine Pomace Product Inhibit Listeria monocytogenes Invasion of Intestinal Cell Lines Caco-2 and SW-480. Foods 2021; 10:foods10071485. [PMID: 34206875 PMCID: PMC8304679 DOI: 10.3390/foods10071485] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/19/2021] [Accepted: 06/22/2021] [Indexed: 11/17/2022] Open
Abstract
Red wine pomace products (WPP) have antimicrobial activities against human pathogens, and it was suggested that they have a probable anti-Listeria effect. This manuscript evaluates the intestinal cell monolayer invasive capacity of Listeria monocytogenes strains obtained from human, salmon, cheese, and L. innocua treated with two WPP (WPP-N and WPP-C) of different polyphenol contents using Caco-2 and SW480 cells. The invasion was dependent of the cell line, being higher in the SW480 than in the Caco-2 cell line. Human and salmon L. monocytogenes strains caused cell invasion in both cell lines, while cheese and L. innocua did not cause an invasion. The phenolic contents of WPP-N are characterized by high levels of anthocyanin and stilbenes and WPP-C by a high content of phenolic acids. The inhibitory effect of the WPPs was dependent of the strain and of the degree of differentiation of the intestinal cells line. The inhibition of Listeria invasion by WPPs in the SW480 cell line, especially with WPP-C, were higher than the Caco-2 cell line inhibited mainly by WPP-N. This effect is associated with the WPPs’ ability to protect the integrity of the intestinal barrier by modification of the cell–cell junction protein expression. The gene expression of E-cadherin and occludin are involved in the L. monocytogenes invasion of both the Caco-2 and SW480 cell lines, while the gene expression of claudin is only involved in the invasion of SW480. These findings suggest that WPPs have an inhibitory L. monocytogenes invasion effect in gastrointestinal cells lines.
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12
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Nitulescu G, Margina D, Zanfirescu A, Olaru OT, Nitulescu GM. Targeting Bacterial Sortases in Search of Anti-Virulence Therapies with Low Risk of Resistance Development. Pharmaceuticals (Basel) 2021; 14:ph14050415. [PMID: 33946434 PMCID: PMC8147154 DOI: 10.3390/ph14050415] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 04/27/2021] [Accepted: 04/27/2021] [Indexed: 12/29/2022] Open
Abstract
Increasingly ineffective antibiotics and rapid spread of multi- and pan-resistant bacteria represent a global health threat; hence, the need of developing new antimicrobial medicines. A first step in this direction is identifying new molecular targets, such as virulence factors. Sortase A represents a virulence factor essential for the pathogenesis of Gram-positive pathogens, some of which have a high risk for human health. We present here an exhaustive collection of sortases inhibitors grouped by relevant chemical features: vinyl sulfones, 3-aryl acrylic acids and derivatives, flavonoids, naphtoquinones, anthraquinones, indoles, pyrrolomycins, isoquinoline derivatives, aryl β-aminoethyl ketones, pyrazolethiones, pyridazinones, benzisothiazolinones, 2-phenyl-benzoxazole and 2-phenyl-benzofuran derivatives, thiadiazoles, triazolothiadiazoles, 2-(2-phenylhydrazinylidene)alkanoic acids, and 1,2,4-thiadiazolidine-3,5-dione. This review focuses on highlighting their structure–activity relationships, using the half maximal inhibitory concentration (IC50), when available, as an indicator of each compound effect on a specific sortase. The information herein is useful for acquiring knowledge on diverse natural and synthetic sortases inhibitors scaffolds and for understanding the way their structural variations impact IC50. It will hopefully be the inspiration for designing novel effective and safe sortase inhibitors in order to create new anti-infective compounds and to help overcoming the current worldwide antibiotic shortage.
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Xu Y, Wei L, Wang Y, Ding L, Guo Y, Sun X, Kong Y, Guo L, Guo T, Sun L. Inhibitory Effect of the Traditional Chinese Medicine Ephedra sinica granules on Streptococcus pneumoniae Pneumolysin. Biol Pharm Bull 2021; 43:994-999. [PMID: 32475921 DOI: 10.1248/bpb.b20-00034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Streptococcus pneumoniae (S. pneumoniae) is an opportunistic pathogen that causes pneumonia, meningitis and bacteremia in humans and animals. Pneumolysin (PLY), a major pore-forming toxin that is important for S. pneumoniae pathogenicity, is a promising target for the development of anti-infective agents. Ephedra sinica granules (ESG) is one of the oldest medical preparation with multiple biological activities (such as a divergent wind and cold effect); however, the detailed mechanism remains unknown. In this study, we found that ESG treatment significantly inhibited the oligomerization of PLY and then reduced the activity of PLY without affecting S. pneumoniae growth and PLY production. In a PLY and A549 cell co-incubation system, the addition of ESG resulted in significant protection against PLY-mediated cell injury. Furthermore, S. pneumoniae-infected mice showed decreased mortality, and alleviated tissue damage and inflammatory reactions following treatment with ESG. Our results indicate that ESG is a potential candidate treatment for S. pneumoniae infection that targets PLY. This finding partially elucidates the mechanism of the Chinese herbal formula ESG in the treatment of pneumococcal disease.
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Affiliation(s)
- Yan Xu
- Changchun University of Chinese Medicine
| | - Lina Wei
- Changchun University of Chinese Medicine
| | - Yanbo Wang
- Changchun University of Chinese Medicine
| | - Lizhong Ding
- Affiliated Hospital of Changchun University of Chinese Medicine
| | - Yinan Guo
- Affiliated Hospital of Changchun University of Chinese Medicine
| | | | - Yibu Kong
- Changchun University of Chinese Medicine
| | - Lei Guo
- Changchun University of Chinese Medicine
| | | | - Liping Sun
- Changchun University of Chinese Medicine
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14
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Qi Z, Guo Y, Zhang H, Yu Q, Zhang P. Betulin attenuates pneumolysin-induced cell injury and DNA damage. J Appl Microbiol 2020; 130:843-851. [PMID: 32621771 DOI: 10.1111/jam.14769] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 06/23/2020] [Accepted: 06/29/2020] [Indexed: 12/19/2022]
Abstract
AIMS Pneumolysin, a pore-forming toxin, is an important virulence factor of Streptococcus pneumoniae with multiple biological activity, such as cell lysis and DNA damage. Thus, targeting this toxin is alternative strategy for the treatment of S. pneumoniae infection. METHODS AND RESULTS Haemolysin assay was performed to identify the potential PLY inhibitor. The mechanism by which betulin, a natural compound from birch bark, against PLY was determined via MICs determination, western blot analysis and oligomerization analysis. Cytotoxicity and Immunofluorescence assays were further used to evaluate the protection of betulin against PLY-induced cell injury and DNA damage. Here, betulin, a natural compound from birch bark, was indentified as an effective inhibitor of PLY. Importantly, at the concentrations required for such inhibition, betulin has no influence on S. pneumoniae viability or PLY production. The interaction of betulin with PLY restrict the olgomerizaiton of this toxin and, thus, directly neutralizing the activity of PLY. Additionally, betulin treatment alleviate PLY induced cells injury and DNA damage in the co-culture system of PLY and A549 cells. CONCLUSIONS Betulin could be used as a promising leading compound against S. pneumoniae virulence by directly targeting PLY without antibacterial activity. SIGNIFICANCE AND IMPACT OF THE STUDY The results presented in this work provided a novel strategy and candidate for S. pneumoniae infection.
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Affiliation(s)
- Z Qi
- Department of Thoracic Surgery, the First Hospital of Jilin University, Changchun, Jilin, China.,Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Y Guo
- Department of Thoracic Surgery, the First Hospital of Jilin University, Changchun, Jilin, China.,Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - H Zhang
- Department of Thoracic Surgery, the First Hospital of Jilin University, Changchun, Jilin, China.,Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Q Yu
- Jilin Provincial Animal Disease Control Center, Changchun, China
| | - P Zhang
- Department of Thoracic Surgery, the First Hospital of Jilin University, Changchun, Jilin, China
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15
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Single-dose treatment for cutaneous leishmaniasis with an easily synthesized chalcone entrapped in polymeric microparticles. Parasitology 2020; 147:1032-1037. [PMID: 32364107 DOI: 10.1017/s0031182020000712] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Cutaneous leishmaniasis (CL) is a major health problem in many countries and its current treatment involves multiple parenteral injections with toxic drugs and requires intensive health services. Previously, the efficacy of a single subcutaneous injection with a slow-release formulation consisting of poly(lactide-co-glycolide) (PLGA) microparticles loaded with an antileishmanial 3-nitro-2-hydroxy-4,6-dimethoxychalcone (CH8) was demonstrated in mice model. In the search for more easily synthesized active chalcone derivatives, and improved microparticle loading, CH8 analogues were synthesized and tested for antileishmanial activity in vitro and in vivo. The 3-nitro-2',4',6'-trimethoxychalcone (NAT22) analogue was chosen for its higher selectivity against intracellular amastigotes (selectivity index = 1489, as compared with 317 for CH8) and more efficient synthesis (89% yield, as compared with 18% for CH8). NAT22 was loaded into PLGA / polyvinylpyrrolidone (PVP) polymeric blend microspheres (NAT22-PLGAk) with average diameter of 1.9 μm. Although NAT22-PLGAk showed similar activity to free NAT22 in killing intracellular parasites in vitro (IC50 ~ 0.2 μm), in vivo studies in Leishmania amazonensis - infected mice demonstrated the significant superior efficacy of NAT22-PLGAk to reduce the parasite load. A single intralesional injection with NAT22-PLGAk was more effective than eight injections with free NAT22. Together, these results show that NAT22-PLGAk is a promising alternative for single-dose localized treatment of CL.
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16
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Çakır V. Functional chalcone-substituted tetrakis-metallophthalocyanines: Synthesis and spectroscopic characterization. JOURNAL OF CHEMICAL RESEARCH 2019. [DOI: 10.1177/1747519819893047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this study, a new phthalonitrile derivative, ( E)-4-(3-(3-(3-methoxyphenyl)acryloyl)phenoxy)phthalonitrile, and four peripherally ( E)-4-(3-(3-(3-methoxyphenyl)acryloyl)phenoxy) tetrasubstituted new Ni(II), Zn(II), Co(II), and Cu(II) phthalocyanine derivatives are synthesized and characterized. ( E)-4-(3-(3-(3-Methoxyphenyl)acryloyl)phenoxy)phthalonitrile is synthesized by heating ( E)-1-(3-hydroxyphenyl)-3-(3-methoxyphenyl)prop-2-en-1-one and 4-nitrophthalonitrile in the presence of K2CO3 in dry DMF at 60°C for 96 h. The metallophthalocyanines are prepared by cyclotetramerization of ( E)-4-(3-(3-(3-methoxyphenyl)acryloyl)phenoxy)phthalonitrile with NiCl2, Zn(CH3COO)2, CoCl2, and CuCl2 in n-pentanol in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene. Characterization of the new compounds is performed by means of IR, 1H NMR, 13C NMR, and mass and UV-Vis spectroscopy techniques.
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Affiliation(s)
- Volkan Çakır
- Department of Property Protection and Security, Emergency and Disaster Management Program, Espiye Vocational School, Giresun University, Giresun, Turkey
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17
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Ayoola MB, Shack LA, Nakamya MF, Thornton JA, Swiatlo E, Nanduri B. Polyamine Synthesis Effects Capsule Expression by Reduction of Precursors in Streptococcus pneumoniae. Front Microbiol 2019; 10:1996. [PMID: 31555234 PMCID: PMC6727871 DOI: 10.3389/fmicb.2019.01996] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Accepted: 08/15/2019] [Indexed: 12/20/2022] Open
Abstract
Streptococcus pneumoniae (pneumococcus, Spn) colonizes the human nasopharynx asymptomatically but can cause infections such as otitis media, and invasive pneumococcal disease such as community-acquired pneumonia, meningitis, and sepsis. Although the success of Spn as a pathogen can be attributed to its ability to synthesize and regulate capsular polysaccharide (CPS) for survival in the host, the mechanisms of CPS regulation are not well-described. Recent studies from our lab demonstrate that deletion of a putative polyamine biosynthesis gene (ΔcadA) in Spn TIGR4 results in the loss of the capsule. In this study, we characterized the transcriptome and metabolome of ΔcadA and identified specific mechanisms that could explain the regulatory role of polyamines in pneumococcal CPS biosynthesis. Our data indicate that impaired polyamine synthesis impacts galactose to glucose interconversion via the Leloir pathway which limits the availability of UDP-galactose, a precursor of serotype 4 CPS, and UDP-N-acetylglucosamine (UDP-GlcNAc), a nucleotide sugar precursor that is at the intersection of CPS and peptidoglycan repeat unit biosynthesis. Reduced carbon flux through glycolysis, coupled with altered fate of glycolytic intermediates further supports impaired synthesis of UDP-GlcNAc. A significant increase in the expression of transketolases indicates a potential shift in carbon flow toward the pentose phosphate pathway (PPP). Higher PPP activity could constitute oxidative stress responses in ΔcadA which warrants further investigation. The results from this study clearly demonstrate the potential of polyamine synthesis, targeted for cancer therapy in human medicine, for the development of novel prophylactic and therapeutic strategies for treating bacterial infections.
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Affiliation(s)
- Moses B Ayoola
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, MS, United States
| | - Leslie A Shack
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, MS, United States
| | - Mary F Nakamya
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, MS, United States
| | - Justin A Thornton
- Department of Biological Sciences, Mississippi State University, Starkville, MS, United States
| | - Edwin Swiatlo
- Section of Infectious Diseases, Southeast Louisiana Veterans Health Care System, New Orleans, LA, United States
| | - Bindu Nanduri
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, MS, United States.,Institute for Genomics, Biocomputing and Biotechnology, Mississippi State University, Starkville, MS, United States
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18
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Li G, Wang G, Wang S, Deng Y. Ginkgetin in vitro and in vivo reduces Streptococcus suis virulence by inhibiting suilysin activity. J Appl Microbiol 2019; 127:1556-1563. [PMID: 31260158 DOI: 10.1111/jam.14365] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 06/13/2019] [Accepted: 06/24/2019] [Indexed: 01/27/2023]
Abstract
AIMS Suilysin (SLY), a crucial virulence-related factor, has multiple cytotoxicities that are regarded as playing a key role in several diseases induced by Streptococcus suis. The aim of this study was to identify an effective inhibitor of SLY and to evaluate the potential inhibitory effect of the inhibitor against S. suis virulence. METHODS AND RESULTS Antibacterial activity experiments and haemolysis tests were used to identify the SLY inhibitor ginkgetin, and Western blot analysis and oligomerization inhibition tests were employed to determine the potential mechanism for its inhibition effect. The potential inhibitory effect of ginkgetin against S. suis virulence was then assessed through a cytotoxicity test and a mouse infection model. In this study, we demonstrated that the natural ingredient ginkgetin can significantly reduce the haemolytic activity of SLY to protect against S. suis-mediated cell injury in vitro by directly binding to SLY to block the oligomerization of the protein and reducing the bacterial burden in vivo. CONCLUSIONS The results suggest that ginkgetin can start being used as a potential lead drug for the treatment of S. suis infections. SIGNIFICANCE AND IMPACT OF THE STUDY The prevention and treatment of S. suis infection might be possible through the targeting of SLY by ginkgetin.
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Affiliation(s)
- G Li
- Department of Respiratory Medicine, The First Hospital of Jilin University, Changchun, Jilin, China.,Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - G Wang
- Department of Respiratory Medicine, The First Hospital of Jilin University, Changchun, Jilin, China.,Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - S Wang
- Department of Radiology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, China
| | - Y Deng
- Department of Respiratory Medicine, The First Hospital of Jilin University, Changchun, Jilin, China.,Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
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19
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Wang J, Liu S, Liu B, Niu X, Deng X. Luteolin Inhibits Listeriolysin O Translation by Directly Targeting the Coding Region of the hly mRNA. Front Microbiol 2019; 10:1496. [PMID: 31312194 PMCID: PMC6614183 DOI: 10.3389/fmicb.2019.01496] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 06/14/2019] [Indexed: 11/16/2022] Open
Abstract
Listeriolysin O (LLO) is necessary for bacterial escape from the phagosome into the cytoplasm, which suggests that targeting LLO may be an alternative strategy to combat Listeria monocytogenes-mediated infection. Here, luteolin, a natural compound without anti-bacterial activity, as indentified as effective inhibitor of LLO by translationally inhibiting the production of LLO. Additionally, luteolin-treated L. monocytogenes displayed reductions in cytoplasmic growth, cytotoxicity and phagosome escape within macrophages. Molecular modeling and mutational analysis revealed a direct interaction between luteolin and the 5′ coding region (A818, U819, G820, and U830 located in nt 814–849) of the mRNA of hly, the gene encoding LLO, which interfered with its translation. Together, our data demonstrate that luteolin may be used as a novel therapeutic and lead compound for treating L. monocytogenes infection.
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Affiliation(s)
- Jianfeng Wang
- Department of Respiratory Medicine, The First Hospital of Jilin University, Changchun, China.,Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Shui Liu
- Department of Respiratory Medicine, The First Hospital of Jilin University, Changchun, China.,Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Bowen Liu
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xiaodi Niu
- Department of Respiratory Medicine, The First Hospital of Jilin University, Changchun, China.,Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xuming Deng
- Department of Respiratory Medicine, The First Hospital of Jilin University, Changchun, China.,Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
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20
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Tang F, Li L, Meng XM, Li B, Wang CQ, Wang SQ, Wang TL, Tian YM. Inhibition of alpha-hemolysin expression by resveratrol attenuates Staphylococcus aureus virulence. Microb Pathog 2019; 127:85-90. [DOI: 10.1016/j.micpath.2018.11.027] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 11/19/2018] [Accepted: 11/19/2018] [Indexed: 12/24/2022]
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21
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DNA-binding, enzyme inhibition, and photochemical properties of chalcone-containing metallophthalocyanine compounds. Bioorg Chem 2018; 81:71-78. [DOI: 10.1016/j.bioorg.2018.08.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Revised: 08/01/2018] [Accepted: 08/03/2018] [Indexed: 01/11/2023]
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22
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Wang G, Gao Y, Wang H, Niu X, Wang J. Baicalin Weakens Staphylococcus aureus Pathogenicity by Targeting Sortase B. Front Cell Infect Microbiol 2018; 8:418. [PMID: 30555803 PMCID: PMC6284026 DOI: 10.3389/fcimb.2018.00418] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 11/13/2018] [Indexed: 11/27/2022] Open
Abstract
Staphylococcus aureus (S. aureus) is a human and other animal pathogen that contributes to the primary etiology of nosocomial pneumonia, a disease with high mortality rates and costs. Treatment of multidrug-resistant S. aureus infection is extremely challenging, and new therapeutic strategies beyond antibiotic treatment are needed. Anti-virulence agents that specifically target the molecular determinants of virulence may be a novel method for treating drug-resistant nosocomial infections. Sortase B (SrtB) is a crucial virulence factor in S. aureus and plays an important role during infection. In this study, we find that baicalin suppresses the activity of SrtB. Minimum inhibitory concentration and growth curve assays confirmed that baicalin has no anti-S. aureus properties. We performed live/dead, lactate dehydrogenase (LDH), adherence, and enzyme-linked immunosorbent assays to confirm that baicalin reduced human alveolar epithelial A549 cell injury caused by S. aureus, reduced the adherence of S. aureus to A549 cells, and significantly attenuated the inflammatory response of mouse macrophage J774 cells to S. aureus. Additionally, we were able to elucidate the binding mechanics and identify the interacting sites of baicalin and SrtB via a molecular dynamics simulation, site-directed mutagenesis, and fluorescence spectroscopy quenching. Finally, we confirmed that baicalin directly binds to the active center of SrtB, and the residues Asn92 and Tyr128 perform an important function in the interaction of SrtB and baicalin. Taken together, these data indicate that baicalin is a promising candidate to combat S. aureus infections.
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Affiliation(s)
- Guizhen Wang
- College of Food Science and Engineering, Jilin University, Changchun, China
| | - Yawen Gao
- College of Food Science and Engineering, Jilin University, Changchun, China
| | - Hongsu Wang
- College of Food Science and Engineering, Jilin University, Changchun, China
| | - Xiaodi Niu
- College of Food Science and Engineering, Jilin University, Changchun, China
| | - Jianfeng Wang
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
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23
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Wang G, Gao Y, Wang H, Wang J, Niu X. Phloretin reduces cell injury and inflammation mediated by Staphylococcus aureus via targeting sortase B and the molecular mechanism. Appl Microbiol Biotechnol 2018; 102:10665-10674. [DOI: 10.1007/s00253-018-9376-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 08/29/2018] [Accepted: 09/05/2018] [Indexed: 01/29/2023]
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24
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New chalcone compound as a promising antileishmanial drug for an old neglected disease: Biological evaluation using radiolabelled biodistribution. J Glob Antimicrob Resist 2018; 13:139-142. [DOI: 10.1016/j.jgar.2017.11.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 11/19/2017] [Accepted: 11/21/2017] [Indexed: 11/18/2022] Open
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25
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Wang G, Wang X, Sun L, Gao Y, Niu X, Wang H. Novel Inhibitor Discovery of Staphylococcus aureus Sortase B and the Mechanism Confirmation via Molecular Modeling. Molecules 2018; 23:molecules23040977. [PMID: 29690584 PMCID: PMC6017250 DOI: 10.3390/molecules23040977] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/04/2018] [Accepted: 04/11/2018] [Indexed: 12/24/2022] Open
Abstract
SortaseB (SrtB) plays a critical role in Staphylococcus aureus (S. aureus) infections. According to the reports in the literature, SrtB can anchor the IsdC to the cell wall to capture iron from the host to achieve a successful invasion. On the other hand, SrtB could also affect the adhesion of S. aureus to host cells based on previous studies. Here, we report about a novel SrtB inhibitor, coptisine, a natural compound that does not exhibit antibacterial activity but can inhibit the SrtB activity in vitro. A cytotoxicity test indicated that coptisine protects human lung epithelial cells from S. aureus. In addition, coptisine can reduce the adhesion of S. aureus to human lung epithelial cells based on the result of plate colony counting assay. Molecular dynamics simulation revealed that coptisine can bind to the active pocket of SrtB, leading to its activity loss. Through the calculation of binding free energy between ligand and protein, site-directed mutagenesis and fluorescence spectroscopy quenching methods, it was confirmed that residues of Arg115, Asn116, and Ile182 played a vital role in the interaction of SrtB with coptisine. These data provide the theoretical basis for the therapy option to the infections caused by S. aureus.
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Affiliation(s)
- Guizhen Wang
- College of Food Science and Engineering, Jilin University, Changchun 130062, China.
| | - Xiyan Wang
- College of Food Science and Engineering, Jilin University, Changchun 130062, China.
| | - Lin Sun
- College of Food Science and Engineering, Jilin University, Changchun 130062, China.
| | - Yawen Gao
- College of Food Science and Engineering, Jilin University, Changchun 130062, China.
| | - Xiaodi Niu
- College of Food Science and Engineering, Jilin University, Changchun 130062, China.
| | - Hongsu Wang
- College of Food Science and Engineering, Jilin University, Changchun 130062, China.
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26
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Eriodictyol protects against Staphylococcus aureus-induced lung cell injury by inhibiting alpha-hemolysin expression. World J Microbiol Biotechnol 2018; 34:64. [PMID: 29671126 DOI: 10.1007/s11274-018-2446-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 04/14/2018] [Indexed: 10/17/2022]
Abstract
Staphylococcus aureus (S. aureus) is a common pathogenic bacterium that causes various diseases in both humans and animals. With the increased prevalence of methicillin-resistant S. aureus, the therapeutic effects of commonly used antibiotics are limited against S. aureus infection. Novel treatment strategies and new antibiotics are needed urgently to address this concern. Many studies have shown that virulence factors secreted from S. aureus play vital roles in their pathogenic processes. Alpha-hemolysin (Hla), an important exotoxin in S. aureus, is one such virulence factor that increases sensitivity of multiple host cells to S. aureus resulting in various diseases. Eriodictyol is a flavonoid compound that exists in many fruits and vegetables. In this study, eriodictyol was demonstrated to inhibit the expression of Hla by hemolysis assays, western blotting, and RT-qPCR at the sub-minimal inhibitory concentration. In live/dead and cytotoxicity assays, the results showed that eriodictyol protected A549 cells against Hla-induced injury in a dose-dependent manner. The minimal inhibitory concentration of eriodictyol against S. aureus was 512 µg/mL. Eriodictyol can downregulate S. aureus Hla at both the expressional and transcriptional levels without affecting S. aureus growth. In addition, cell assays had proved that eriodictyol could protect A549 cells against Hla damage. Eriodictyol could therefore have the potential to treat S. aureus infection targeting Hla.
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27
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Liu Y, Orsi RH, Boor KJ, Wiedmann M, Guariglia-Oropeza V. Home Alone: Elimination of All but One Alternative Sigma Factor in Listeria monocytogenes Allows Prediction of New Roles for σ B. Front Microbiol 2017; 8:1910. [PMID: 29075236 PMCID: PMC5641562 DOI: 10.3389/fmicb.2017.01910] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Accepted: 09/19/2017] [Indexed: 11/13/2022] Open
Abstract
Among Listeria monocytogenes' four alternative σ factors, σB controls the largest regulon. As σB-dependent transcription of some genes may be masked by overlaps among regulons, and as some σB-dependent genes are expressed only under very specific conditions, we hypothesized that the σB regulon is not yet fully defined. To further extend our understanding of the σB regulon, we used RNA-seq to identify σB-dependent genes in an L. monocytogenes strain that expresses σB following rhamnose induction, and in which genes encoding the other alternative sigma factors have been deleted. Analysis of RNA-seq data with multiple bioinformatics approaches, including a sliding window method that detects differentially transcribed 5' untranslated regions (UTRs), identified 105 σB-dependent transcription units (TUs) comprising 201 genes preceded by σB-dependent promoters. Of these 105 TUs, 7 TUs comprising 15 genes had not been identified previously as σB-dependent. An additional 23 genes not reported previously as σB-dependent were identified in 9 previously recognized σB-dependent TUs. Overall, 38 of these 201 genes had not been identified previously as members of the L. monocytogenes σB regulon. These newly identified σB-dependent genes encode proteins annotated as being involved in transcriptional regulation, oxidative and osmotic stress response, and in metabolism of energy, carbon and nucleotides. In total, 18 putative σB-dependent promoters were newly identified. Interestingly, a number of genes previously identified as σB-dependent did not show significant evidence for σB-dependent transcription in our experiments. Based on promoter analyses, a number of these genes showed evidence for co-regulation by σB and other transcriptional factors, suggesting that some σB-dependent genes require additional transcriptional regulators along with σB for transcription. Over-expression of a single alternative sigma factor in the absence of all other alternative sigma factors allowed us to: (i) identify new σB-dependent functions in L. monocytogenes, such as regulation of genes involved in 1,2-propanediol utilization (LMRG_00594-LMRG_00611) and biosynthesis of pyrimidine nucleotides (LMRG_00978-LMRG_00985); and (ii) identify new σB-dependent genes involved in stress response and pathogenesis functions. These data further support that σB not only regulates stress response functions, but also plays a broad role in L. monocytogenes homeostasis and resilience.
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Affiliation(s)
- Yichang Liu
- Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Renato H Orsi
- Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Kathryn J Boor
- Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Martin Wiedmann
- Department of Food Science, Cornell University, Ithaca, NY, United States
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Zhang B, Teng Z, Li X, Lu G, Deng X, Niu X, Wang J. Chalcone Attenuates Staphylococcus aureus Virulence by Targeting Sortase A and Alpha-Hemolysin. Front Microbiol 2017; 8:1715. [PMID: 28932220 PMCID: PMC5592744 DOI: 10.3389/fmicb.2017.01715] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 08/24/2017] [Indexed: 12/21/2022] Open
Abstract
Staphylococcus aureus (S.aureus) resistance, considered a dilemma for the clinical treatment of this bacterial infection, is becoming increasingly intractable. Novel anti-virulence strategies will undoubtedly provide a path forward in combating these resistant bacterial infections. Sortase A (SrtA), an enzyme responsible for anchoring virulence-related surface proteins, and alpha-hemolysin (Hla), a pore-forming cytotoxin, have aroused great scientific interest, as they have been regarded as targets for promising agents against S. aureus infection. In this study, we discovered that chalcone, a natural small compound with little anti-S. aureus activity, could significantly inhibit SrtA activity with an IC50 of 53.15 μM and Hla hemolysis activity with an IC50 of 17.63 μM using a fluorescence resonance energy transfer (FRET) assay and a hemolysis assay, respectively. In addition, chalcone was proven to reduce protein A (SpA) display in intact bacteria, binding to fibronectin, formation of biofilm and S. aureus invasion. Chalcone could down-regulate the transcriptional levels of the hla gene and the agrA gene, thus leading to a reduction in the expression of Hla and significant protection against Hla-mediated A549 cell injury; more importantly, chalcone could also reduce mortality in infected mice. Additionally, molecular dynamics simulations and mutagenesis assays were used to identify the mechanism of chalcone against SrtA, which implied that the inhibitory activity lies in the bond between chalcone and SrtA residues Val168, Ile182, and Arg197. Taken together, the in vivo and in vitro experiments suggest that chalcone is a potential novel therapeutic compound for S. aureus infection via targeting SrtA and Hla.
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Affiliation(s)
- Bing Zhang
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin UniversityChangchun, China.,Center of Infection and Immunity, The First Hospital, Jilin UniversityChangchun, China
| | - Zihao Teng
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin UniversityChangchun, China
| | - Xianhe Li
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin UniversityChangchun, China
| | - Gejin Lu
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin UniversityChangchun, China
| | - Xuming Deng
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin UniversityChangchun, China.,Center of Infection and Immunity, The First Hospital, Jilin UniversityChangchun, China
| | - Xiaodi Niu
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin UniversityChangchun, China
| | - Jianfeng Wang
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin UniversityChangchun, China.,Center of Infection and Immunity, The First Hospital, Jilin UniversityChangchun, China
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29
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Song M, Teng Z, Li M, Niu X, Wang J, Deng X. Epigallocatechin gallate inhibits Streptococcus pneumoniae virulence by simultaneously targeting pneumolysin and sortase A. J Cell Mol Med 2017; 21:2586-2598. [PMID: 28402019 PMCID: PMC5618700 DOI: 10.1111/jcmm.13179] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 02/24/2017] [Indexed: 01/11/2023] Open
Abstract
Streptococcus pneumoniae (pneumococcus), the causative agent of several human diseases, possesses numerous virulence factors associated with pneumococcal infection and pathogenesis. Pneumolysin (PLY), an important virulence factor, is a member of the cholesterol-dependent cytolysin family and has cytolytic activity. Sortase A (SrtA), another crucial pneumococcal virulence determinate, contributes greatly to the anchoring of many virulence-associated surface proteins to the cell wall. In this study, epigallocatechin gallate (EGCG), a natural compound with little known antipneumococcal activity, was shown to directly inhibit PLY-mediated haemolysis and cytolysis by blocking the oligomerization of PLY and simultaneously reduce the peptidase activity of SrtA. The biofilm formation, production of neuraminidase A (NanA, the pneumococcal surface protein anchored by SrtA), and bacterial adhesion to human epithelial cells (Hep2) were inhibited effectively when S. pneumoniae D39 was cocultured with EGCG. The results from molecular dynamics simulations and mutational analysis confirmed the interaction of EGCG with PLY and SrtA, and EGCG binds to Glu277, Tyr358, and Arg359 in PLY and Thr169, Lys171, and Phe239 in SrtA. In vivo studies further demonstrated that EGCG protected mice against S. pneumoniae pneumonia. Our results imply that EGCG is an effective inhibitor of both PLY and SrtA and that an antivirulence strategy that directly targets PLY and SrtA using EGCG is a promising therapeutic option for S. pneumoniae pneumonia.
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Affiliation(s)
- Meng Song
- The First Hospital and Institute of Infection and Immunity, Jilin University, Changchun, China.,Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Zihao Teng
- The First Hospital and Institute of Infection and Immunity, Jilin University, Changchun, China.,Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Meng Li
- The First Hospital and Institute of Infection and Immunity, Jilin University, Changchun, China.,Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xiaodi Niu
- The First Hospital and Institute of Infection and Immunity, Jilin University, Changchun, China.,Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jianfeng Wang
- The First Hospital and Institute of Infection and Immunity, Jilin University, Changchun, China.,Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xuming Deng
- The First Hospital and Institute of Infection and Immunity, Jilin University, Changchun, China
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30
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Wang J, Liu B, Teng Z, Zhou X, Wang X, Zhang B, Lu G, Niu X, Yang Y, Deng X. Phloretin Attenuates Listeria monocytogenes Virulence Both In vitro and In vivo by Simultaneously Targeting Listeriolysin O and Sortase A. Front Cell Infect Microbiol 2017; 7:9. [PMID: 28154809 PMCID: PMC5244253 DOI: 10.3389/fcimb.2017.00009] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 01/05/2017] [Indexed: 01/05/2023] Open
Abstract
The critical roles of sortase A (SrtA) and listeriolysin O (LLO) in Listeria monocytogenes pathogenicity render these two virulence factors as ideal targets for the development of anti-virulence agents against L. monocytogenes infection. Additionally, the structures of SrtA and LLO are highly conserved among the members of sortase enzyme family and cholesterol dependent toxin family. Here, phloretin, a natural polyphenolic compound derived from apples and pears that has little anti-L. monocytogenes activity, was identified to simultaneously inhibit LLO expression and neutralize SrtA catalytic activity. Phloretin neutralized SrtA activity by causing a conformational change in the protein's active pocket, which prevented engagement with its substrate. Treatment with phloretin simultaneously reduced L. monocytogenes invasion into host cells and blocked the escape of vacuole-entrapped L. monocytogenes into cytoplasm. Further, L. monocytogenes-infected mice that received phloretin showed lower mortality, decreased bacterial burden and reduced pathological injury. Our results demonstrate that phloretin is a promising anti-infective therapeutic for infections caused by L. monocytogenes due to its simultaneous targeting of SrtA and LLO, which may result in fewer side effects than those caused by other antibiotics.
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Affiliation(s)
- Jianfeng Wang
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University Changchun, China
| | - Bowen Liu
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University Changchun, China
| | - Zihao Teng
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University Changchun, China
| | - Xuan Zhou
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University Changchun, China
| | - Xiyan Wang
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University Changchun, China
| | - Bing Zhang
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University Changchun, China
| | - Gejin Lu
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University Changchun, China
| | - Xiaodi Niu
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University Changchun, China
| | - Yongjun Yang
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University Changchun, China
| | - Xuming Deng
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University Changchun, China
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31
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Chen J, Dong H, Murfin KE, Feng C, Wu S, Zheng B. Active site analysis of sortase A from Staphylococcus simulans indicates function in cleavage of putative cell wall proteins. Biochem Biophys Res Commun 2016; 478:1653-9. [PMID: 27591898 DOI: 10.1016/j.bbrc.2016.08.175] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 08/30/2016] [Indexed: 12/22/2022]
Abstract
Sortase mediated transpeptidation reactions play a significant role in covalent attachment of surface proteins to the cell wall of Gram-positive bacteria. Earlier studies have shown that sortase A (StrA) is required for the virulence of Staphylococci. The human pathogen Staphylococcus simulans CJ16 carries a putative sortase A (SsiStrA) encoding gene, but neither transpeptidation activity nor biochemical characteristics of SsiStrA have been investigated. Here, we identified and characterized StrA from coagulase-negative Staphylococci. SsiStrA was cloned and overexpressed in Escherichia coli BL21 in a soluble form. Size-exclusion chromatography, cross-linking and dynamic light scattering demonstrated that SsiStrA existed as monomer-dimer equilibrium in vitro. We further demonstrated that SsiStrA has sortase activity, and it recognized and cleaved the sorting motif LXPTG. H117, C180 and R193 residues were critical for enzyme activity, and calcium ions enhanced activity.
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Affiliation(s)
- Jian Chen
- Intensive Care Unit, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Huihui Dong
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Kristen E Murfin
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, USA
| | - Chunyan Feng
- Institute of Animal Quarantine, Chinese Academy of Inspection and Quarantine, Beijing, China
| | - Shaoqiang Wu
- Institute of Animal Quarantine, Chinese Academy of Inspection and Quarantine, Beijing, China.
| | - Beiwen Zheng
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.
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