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Vadakkan K, Sathishkumar K, Kuttiyachan Urumbil S, Ponnenkunnathu Govindankutty S, Kumar Ngangbam A, Devi Nongmaithem B. A review of chemical signaling mechanisms underlying quorum sensing and its inhibition in Staphylococcus aureus. Bioorg Chem 2024; 148:107465. [PMID: 38761705 DOI: 10.1016/j.bioorg.2024.107465] [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: 03/24/2024] [Revised: 04/29/2024] [Accepted: 05/14/2024] [Indexed: 05/20/2024]
Abstract
Staphylococcus aureus is a significant bacterium responsible for multiple infections and is a primary cause of fatalities among patients in hospital environments. The advent of pathogenic bacteria such as methicillin-resistant S. aureus revealed the shortcomings of employing antibiotics to treat bacterial infectious diseases. Quorum sensing enhances S. aureus's survivability through signaling processes. Targeting the key components of quorum sensing has drawn much interest nowadays as a promising strategy for combating infections caused by bacteria. Concentrating on the accessory gene regulator quorum-sensing mechanism is the most commonly suggested anti-virulence approach for S.aureus. Quorum quenching is a common strategy for controlling illnesses triggered by microorganisms since it reduces the pathogenicity of bacteria and improves bacterial biofilm susceptibility to antibiotics, thus providing an intriguing prospect for drug discovery. Quorum sensing inhibition reduces selective stresses and constrains the emergence of antibiotic resistance while limiting bacterial pathogenicity. This review examines the quorum sensing mechanisms involved in S. aureus, quorum sensing targets and gene regulation, environmental factors affecting quorum sensing, quorum sensing inhibition, natural products as quorum sensing inhibitory agents and novel therapeutical strategies to target quorum sensing in S. aureus as drug developing technique to augment conventional antibiotic approaches.
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Affiliation(s)
- Kayeen Vadakkan
- Department of Biotechnology, St. Mary's College (Autonomous), Thrissur, Kerala 680020, India; Manipur International University, Imphal, Manipur 795140, India.
| | - Kuppusamy Sathishkumar
- Center for Global Health Research, Saveetha Medical College and Hospitals, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha University, Thandalam, Chennai, Tamil Nadu 602105, India
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Sabino YNV, de Araújo Domingues KC, O'Connor PM, Marques PH, Santos EH, Tótola MR, Abreu LM, de Queiroz MV, Cotter PD, Mantovani HC. Bacillus velezensis iturins inhibit the hemolytic activity of Staphylococcus aureus. Sci Rep 2024; 14:9469. [PMID: 38658583 PMCID: PMC11043418 DOI: 10.1038/s41598-024-58973-0] [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: 09/08/2023] [Accepted: 04/05/2024] [Indexed: 04/26/2024] Open
Abstract
Bovine mastitis caused by S. aureus has a major economic impact on the dairy sector. With the crucial need for new therapies, anti-virulence strategies have gained attention as alternatives to antibiotics. Here we aimed to identify novel compounds that inhibit the production/activity of hemolysins, a virulence factor of S. aureus associated with mastitis severity. We screened Bacillus strains obtained from diverse sources for compounds showing anti-hemolytic activity. Our results demonstrate that lipopeptides produced by Bacillus spp. completely prevented the hemolytic activity of S. aureus at certain concentrations. Following purification, both iturins, fengycins, and surfactins were able to reduce hemolysis caused by S. aureus, with iturins showing the highest anti-hemolytic activity (up to 76% reduction). The lipopeptides showed an effect at the post-translational level. Molecular docking simulations demonstrated that these compounds can bind to hemolysin, possibly interfering with enzyme action. Lastly, molecular dynamics analysis indicated general stability of important residues for hemolysin activity as well as the presence of hydrogen bonds between iturins and these residues, with longevous interactions. Our data reveals, for the first time, an anti-hemolytic activity of lipopeptides and highlights the potential application of iturins as an anti-virulence therapy to control bovine mastitis caused by S. aureus.
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Affiliation(s)
| | | | | | - Pedro Henrique Marques
- Department of Microbiology, Immunology and Parasitology, Federal University of Triângulo Mineiro, Uberaba, MG, Brazil
| | - Eduardo Horta Santos
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | | | | | | | - Paul D Cotter
- Teagasc Food Research Centre, Moorepark, Fermoy, Co. Cork, Cork, Ireland
- APC Microbiome Ireland, Cork, Ireland
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Zhu Y, Guo PJ, Ding AX, Zheng L, Du GX, Chen T, Qin GQ, Hu XG, Wang WQ, Xuan LJ. Eighteen iridoids from the roots and rhizomes of Valeriana jatamansi and their protective effects against α-hemolysin. PHYTOCHEMISTRY 2024; 219:113962. [PMID: 38185394 DOI: 10.1016/j.phytochem.2023.113962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 12/28/2023] [Accepted: 12/29/2023] [Indexed: 01/09/2024]
Abstract
Thirteen previously undescribed iridoids (1-13), together with five known iridoids (14-18) were isolated from the roots and rhizomes of Valeriana jatamansi Jones. Their structures with absolute configurations were elucidated by analysis of MS, NMR, optical rotation and their experimental and calculated electronic circular dichroism spectra. All of the isolated compounds were tested for their protective effects against α-hemolysin-induced cell death in A549 cells. Compounds 14, 16 and 17 showed moderate protective effects, and compounds 15 and 18 showed weak protective effects.
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Affiliation(s)
- Yao Zhu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 501 Haike Road, Shanghai, 201203, China; University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing, 100049, China
| | - Peng-Ju Guo
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 501 Haike Road, Shanghai, 201203, China; School of Pharmacy, Fudan University, Shanghai, 201203, China
| | - Ao-Xue Ding
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 501 Haike Road, Shanghai, 201203, China; University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing, 100049, China
| | - Liu Zheng
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 501 Haike Road, Shanghai, 201203, China; University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing, 100049, China
| | - Gao-Xiang Du
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 501 Haike Road, Shanghai, 201203, China; School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210029, China
| | - Tong Chen
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 501 Haike Road, Shanghai, 201203, China; School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210029, China
| | - Guo-Qing Qin
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 501 Haike Road, Shanghai, 201203, China; University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing, 100049, China
| | - Xiang-Gang Hu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 501 Haike Road, Shanghai, 201203, China; School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210029, China
| | - Wen-Qiong Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 501 Haike Road, Shanghai, 201203, China.
| | - Li-Jiang Xuan
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 501 Haike Road, Shanghai, 201203, China; University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing, 100049, China; School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210029, China.
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4
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Lou F, Huang H, Li Y, Yang S, Shi Y. Investigation of the inhibitory effect and mechanism of epigallocatechin-3-gallate against Streptococcus suis sortase A. J Appl Microbiol 2023; 134:lxad191. [PMID: 37634082 DOI: 10.1093/jambio/lxad191] [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: 04/21/2023] [Revised: 08/11/2023] [Accepted: 08/25/2023] [Indexed: 08/28/2023]
Abstract
AIMS Streptococcus suis seriously harms people and animals, and importantly, causes great economic losses in the pig industry. Similar to most Gram-positive pathogenic bacteria, sortase A (SrtA) of S. suis can mediate the anchoring of a variety of virulence factors that contain specific sorting sequences to the surface of the bacterial cell wall envelope and participate in pathogenicity. The purpose of this study is to clarify the molecular mechanism of epigallocatechin-3-gallate (EGCG) inhibiting S. suis SrtA and provide more evidence for the development of novel anti-S. suis infections drugs. METHODS AND RESULTS Through the SrtA substrate cleavage experiment, we found that the main component of green tea, EGCG, can effectively inhibit the enzyme activity of S. suis SrtA. Further, molecular docking and molecular dynamics simulation were used to clarify the molecular mechanism of its inhibitory effect, demonstrating that EGCG mainly interacts with amino acids at 113 and 115 to exert its inhibitory function. It was previously found that EGCG can inhibit the growth of S. suis and reduce the activity of suilysin and inhibit its expression. Our research reveals a new function of EGCG in S. suis infection. CONCLUSIONS Our research proves that EGCG can effectively inhibit the transpeptidase activity of SrtA. We also clarify the accompanying molecular mechanism, providing more sufficient evidence for the use of EGCG as a potential lead compound against S. suis infection.
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Affiliation(s)
- Fei Lou
- College of Veterinary Medicine, Henan University of Animal Husbandry and Economy, Zhengzhou, China
| | - Hui Huang
- College of Veterinary Medicine, Henan University of Animal Husbandry and Economy, Zhengzhou, China
| | - Yaping Li
- School of Basic Medical Sciences, Beihua University, Jilin, China
| | - Shuo Yang
- School of Basic Medical Sciences, Beihua University, Jilin, China
| | - Yangqian Shi
- School of Basic Medical Sciences, Beihua University, Jilin, China
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Paternoster C, Tarenzi T, Potestio R, Lattanzi G. Gamma-Hemolysin Components: Computational Strategies for LukF-Hlg2 Dimer Reconstruction on a Model Membrane. Int J Mol Sci 2023; 24:ijms24087113. [PMID: 37108277 PMCID: PMC10138441 DOI: 10.3390/ijms24087113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/07/2023] [Accepted: 04/07/2023] [Indexed: 04/29/2023] Open
Abstract
The gamma-hemolysin protein is one of the most common pore-forming toxins expressed by the pathogenic bacterium Staphylococcus aureus. The toxin is used by the pathogen to escape the immune system of the host organism, by assembling into octameric transmembrane pores on the surface of the target immune cell and leading to its death by leakage or apoptosis. Despite the high potential risks associated with Staphylococcus aureus infections and the urgent need for new treatments, several aspects of the pore-formation process from gamma-hemolysin are still unclear. These include the identification of the interactions between the individual monomers that lead to the formation of a dimer on the cell membrane, which represents the unit for further oligomerization. Here, we employed a combination of all-atom explicit solvent molecular dynamics simulations and protein-protein docking to determine the stabilizing contacts that guide the formation of a functional dimer. The simulations and the molecular modeling reveal the importance of the flexibility of specific protein domains, in particular the N-terminus, to drive the formation of the correct dimerization interface through functional contacts between the monomers. The results obtained are compared with the experimental data available in the literature.
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Affiliation(s)
- Costanza Paternoster
- Department of Physics, University of Trento, Via Sommarive 14, I-38123 Trento, Italy
- INFN-TIFPA, Trento Institute for Fundamental Physics and Applications, Via Sommarive 14, I-38123 Trento, Italy
| | - Thomas Tarenzi
- Department of Physics, University of Trento, Via Sommarive 14, I-38123 Trento, Italy
- INFN-TIFPA, Trento Institute for Fundamental Physics and Applications, Via Sommarive 14, I-38123 Trento, Italy
| | - Raffaello Potestio
- Department of Physics, University of Trento, Via Sommarive 14, I-38123 Trento, Italy
- INFN-TIFPA, Trento Institute for Fundamental Physics and Applications, Via Sommarive 14, I-38123 Trento, Italy
| | - Gianluca Lattanzi
- Department of Physics, University of Trento, Via Sommarive 14, I-38123 Trento, Italy
- INFN-TIFPA, Trento Institute for Fundamental Physics and Applications, Via Sommarive 14, I-38123 Trento, Italy
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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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7
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Sabino YNV, Cotter PD, Mantovani HC. Anti-virulence compounds against Staphylococcus aureus associated with bovine mastitis: A new therapeutic option? Microbiol Res 2023; 271:127345. [PMID: 36889204 DOI: 10.1016/j.micres.2023.127345] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 02/22/2023] [Accepted: 02/26/2023] [Indexed: 03/05/2023]
Abstract
Bovine mastitis represents a major economic burden faced by the dairy industry. S. aureus is an important and prevalent bovine mastitis-associated pathogen in dairy farms worldwide. The pathogenicity and persistence of S. aureus in the bovine mammary gland are associated with the expression of a range of virulence factors involved in biofilm formation and the production of several toxins. The traditional therapeutic approach to treating bovine mastitis includes the use of antibiotics, but the emergence of antibiotic-resistant strains has caused therapeutic failure. New therapeutic approaches targeting virulence factors of S. aureus rather than cell viability can have several advantages including lower selective pressure towards the development of resistance and little impact on the host commensal microbiota. This review summarizes the potential of anti-virulence therapies to control S. aureus associated with bovine mastitis focusing on anti-toxin, anti-biofilm, and anti-quorum sensing compounds. It also points to potential sources of new anti-virulence inhibitors and presents screening strategies for identifying these compounds.
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Affiliation(s)
| | | | - Hilario C Mantovani
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI, USA.
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8
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Melittin Tryptophan Substitution with a Fluorescent Amino Acid Reveals the Structural Basis of Selective Antitumor Effect and Subcellular Localization in Tumor Cells. Toxins (Basel) 2022; 14:toxins14070428. [PMID: 35878166 PMCID: PMC9318513 DOI: 10.3390/toxins14070428] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Revised: 06/14/2022] [Accepted: 06/19/2022] [Indexed: 02/01/2023] Open
Abstract
Melittin is a membrane-active peptide with strong anticancer activity against various cancers. Despite decades of research, the role of the singular Trp in the anticancer activity and selectivity of melittin remains poorly understood. Here, we propose a theranostic solution based on the substitution of Trp19 with a noncanonical fluorescent amino acid (DapAMCA). The introduction of DapAMCA residue in melittin stabilized the helical structure of the peptide, as evaluated by circular dichroism spectra and molecular dynamics simulations. In vitro hemolytic and anticancer activity assays revealed that introducing DapAMCA residue in melittin changed its mode of action with the cell membrane, resulting in reduced hemolytic toxicity and an improved the selectivity index (SI), with up to a five-fold increase compared to melittin. In vitro fluorescence imaging of DapAMCA-labeled melittin (MELFL) in cancer cells demonstrated high membrane-penetrating activity, with strong nuclear and nucleolar localization ability. These findings provide implications for novel anticancer therapies based on Trp-substituted designs and nuclear/nucleolar targeted therapy.
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Guo Y, Yang Y, Xu X, Li L, Zhou Y, Jia G, Wei L, Yu Q, Wang J. Metallo-β-lactamases inhibitor fisetin attenuates meropenem resistance in NDM-1-producing Escherichia coli. Eur J Med Chem 2022; 231:114108. [DOI: 10.1016/j.ejmech.2022.114108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 01/06/2022] [Accepted: 01/07/2022] [Indexed: 11/30/2022]
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You K, Gao B, Wang M, Wang X, Okoro KC, Rakhimbekzoda A, Feng Y. Versatile polymer-based strategies for antibacterial drug delivery systems and antibacterial coatings. J Mater Chem B 2022; 10:1005-1018. [DOI: 10.1039/d1tb02417e] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Human health damage and economic losses due to bacterial infections are very serious worldwide. Excessive use of antibiotics has caused an increase in bacterial resistance. Fortunately, various non-antibiotic antibacterial materials...
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Yin N, Yang X, Wang L, Zhang C, Guan J, Tao Y, Guo X, Zhao Y, Song W, Wang B, Tang Y. Kaempferol inhibits the expression of α-hemolysin and protects mice from methicillin-resistant Staphylococcus aureus-induced lethal pneumonia. Microb Pathog 2021; 162:105336. [PMID: 34856361 DOI: 10.1016/j.micpath.2021.105336] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 11/27/2021] [Accepted: 11/27/2021] [Indexed: 01/15/2023]
Abstract
Staphylococcus aureus (S. aureus) is a common pathogenic bacterium that induces a variety of diseases in humans and animals. The significant pathogenicity of S. aureus is due to its expression of several virulence factors. Alpha-hemolysin (Hla) has attracted attention as a virulence factor in staphylococcal pathogenesis and has been the predominant focus of intense research. In this study, we found that kaempferol, a flavonoid compound, inhibited hemolysis at a low concentration (32 μg/mL) and exerted no effect on bacterial growth. Western blot and RT-qPCR assays further demonstrated that kaempferol downregulated the expression of Hla in S. aureus. We observed that kaempferol alleviated the damage from S. aureus Hla in A549 cells. More importantly, kaempferol showed a potent protective effect on mice pneumonia induced by MRSA, as evidenced by a significant improvement in the survival of mice, a reduction in the number of colonized colonies in lung tissue and a decrease in the pathological damage to lung tissues. In summary, the results demonstrate the protective effect of kaempferol on MRSA-induced lethal pneumonia in mice and indicate that kaempferol could be developed as a potential anti-MRSA drug.
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Affiliation(s)
- Ning Yin
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Xin Yang
- MOE Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China; Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 271016, China
| | - Li Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Chi Zhang
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Jiyu Guan
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, China
| | - Ye Tao
- Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, 130021, China
| | - Xuerui Guo
- Changchun University of Chinese Medicine, Changchun, 130117, China; School of Pharmacy, Jilin University, Changchun, 130021, China
| | - Yicheng Zhao
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Wu Song
- Changchun University of Chinese Medicine, Changchun, 130117, China.
| | - Bingmei Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China.
| | - Yong Tang
- Changchun University of Chinese Medicine, Changchun, 130117, China.
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Feng J, Sun D, Wang L, Li X, Guan J, Wei L, Yue D, Wang X, Zhao Y, Yang H, Song W, Wang B. Biochanin A as an α-hemolysin inhibitor for combating methicillin-resistant Staphylococcus aureus infection. World J Microbiol Biotechnol 2021; 38:6. [PMID: 34837116 DOI: 10.1007/s11274-021-03182-4] [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] [Received: 09/09/2021] [Accepted: 10/28/2021] [Indexed: 12/29/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a multidrug-resistant pathogen that poses a significant risk to global health today. In S. aureus, α-hemolysin is an important virulence factor as it contributes to the capacity of the bacteria to infect the host. Here, we showed that biochanin A (bioA), an isoflavone present in red clover, cabbage and alfalfa, effectively inhibited hemolytic activity at a dose as low as 32 μg/mL. Further, western blot and RT-qPCR data showed that bioA reduced the production and expression of MRSA hemolysin in a dose-dependent manner. In addition, when different concentrations of bioA were added to a coculture system of A549 cells and S. aureus, it could significantly decrease cell injury. Importantly, the in vivo study showed that bioA could protect mice from pneumonia caused by a lethal dose of MRSA, as evidenced by improving their survival and reducing the number of bacterial colonies in lung tissues, the secretion of hemolysin into alveolar lavage fluid and the degree of pulmonary edema. In conclusion, biochanin A protected the host from MRSA infection by inhibiting the expression of the hemolysin of MRSA, which may provide experimental evidence for its development to a potential anti-MRSA drug.
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Affiliation(s)
- Jiaxuan Feng
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Dazhong Sun
- First School of Clinical Medicine, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Li Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Xueting Li
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Jiyu Guan
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, China
| | - Lin Wei
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Donghui Yue
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Xingye Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Yicheng Zhao
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Haimiao Yang
- Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, 130021, China
| | - Wu Song
- Changchun University of Chinese Medicine, Changchun, 130117, China.
| | - Bingmei Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China.
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13
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Sannigrahi A, Chattopadhyay K. Pore formation by pore forming membrane proteins towards infections. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2021; 128:79-111. [PMID: 35034727 DOI: 10.1016/bs.apcsb.2021.09.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Over the last 25 years, the biology of membrane proteins, including the PFPs-membranes interactions is seeking attention for the development of successful drug molecules against a number of infectious diseases. Pore forming toxins (PFTs), the largest family of PFPs are considered as a group of virulence factors produced in a large number of pathogenic systems which include streptococcus, pneumonia, Staphylococcus aureus, E. coli, Mycobacterium tuberculosis, group A and B streptococci, Corynebacterium diphtheria and many more. PFTs are generally utilized by the disease causing pathogens to disrupt the host first line of defense i.e. host cell membranes through pore formation strategy. Although, pore formation is the principal mode of action of the PFTs but they can have additional adverse effects on the hosts including immune evasion. Recently, structural investigation of different PFTs have imparted the molecular mechanistic insights into how PFTs get transformed from its inactive state to active toxic state. On the basis of their structural entity, PFTs have been classified in different types and their mode of actions alters in terms of pore formation and corresponding cellular toxicity. Although pathogen genome analysis can identify the probable PFTs depending upon their structural diversity, there are so many PFTs which utilize the local environmental conditions to generate their pore forming ability using a novel strategy which is known as "conformational switch" of a protein. This conformational switch is considered as characteristics of the phase shifting proteins which were often utilized by many pathogenic systems to protect them from the invaders through allosteric communication between distant regions of the protein. In this chapter, we discuss the structure function relationships of PFTs and how activity of PFTs varies with the change in the environmental conditions has been explored. Finally, we demonstrate these structural insights to develop therapeutic potential to treat the infections caused by multidrug resistant pathogens.
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Affiliation(s)
- Achinta Sannigrahi
- Department of Chemical Engineering, Indian Institute of Science, Bengaluru, Karnataka, India.
| | - Krishnananda Chattopadhyay
- Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, Kolkata, West Bengal, India.
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Ahmad-Mansour N, Loubet P, Pouget C, Dunyach-Remy C, Sotto A, Lavigne JP, Molle V. Staphylococcus aureus Toxins: An Update on Their Pathogenic Properties and Potential Treatments. Toxins (Basel) 2021; 13:677. [PMID: 34678970 PMCID: PMC8540901 DOI: 10.3390/toxins13100677] [Citation(s) in RCA: 91] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 09/18/2021] [Accepted: 09/21/2021] [Indexed: 01/12/2023] Open
Abstract
Staphylococcus aureus is a clinically important pathogen that causes a wide range of human infections, from minor skin infections to severe tissue infection and sepsis. S. aureus has a high level of antibiotic resistance and is a common cause of infections in hospitals and the community. The rising prevalence of community-acquired methicillin-resistant S. aureus (CA-MRSA), combined with the important severity of S. aureus infections in general, has resulted in the frequent use of anti-staphylococcal antibiotics, leading to increasing resistance rates. Antibiotic-resistant S. aureus continues to be a major health concern, necessitating the development of novel therapeutic strategies. S. aureus uses a wide range of virulence factors, such as toxins, to develop an infection in the host. Recently, anti-virulence treatments that directly or indirectly neutralize S. aureus toxins have showed promise. In this review, we provide an update on toxin pathogenic characteristics, as well as anti-toxin therapeutical strategies.
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Affiliation(s)
- Nour Ahmad-Mansour
- Laboratory of Pathogen Host Interactions, CNRS UMR5235, Université de Montpellier, 34000 Montpellier, France;
| | - Paul Loubet
- Virulence Bactérienne et Infections Chroniques, INSERM U1047, Department of Infectious and Tropical Diseases, Université de Montpellier, 30908 Nîmes, France; (P.L.); (A.S.)
| | - Cassandra Pouget
- Virulence Bactérienne et Infections Chroniques, INSERM U1047, Université de Montpellier, 30908 Nîmes, France;
| | - Catherine Dunyach-Remy
- Virulence Bactérienne et Infections Chroniques, INSERM U1047, Department of Microbiology and Hospital Hygiene, Université de Montpellier, 30908 Nîmes, France; (C.D.-R.); (J.-P.L.)
| | - Albert Sotto
- Virulence Bactérienne et Infections Chroniques, INSERM U1047, Department of Infectious and Tropical Diseases, Université de Montpellier, 30908 Nîmes, France; (P.L.); (A.S.)
| | - Jean-Philippe Lavigne
- Virulence Bactérienne et Infections Chroniques, INSERM U1047, Department of Microbiology and Hospital Hygiene, Université de Montpellier, 30908 Nîmes, France; (C.D.-R.); (J.-P.L.)
| | - Virginie Molle
- Laboratory of Pathogen Host Interactions, CNRS UMR5235, Université de Montpellier, 34000 Montpellier, France;
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15
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Hu H, Liu M, Sun S. Pore-Forming Toxins During Bacterial Infection: Molecular Mechanisms and Potential Therapeutic Targets. DRUG DESIGN DEVELOPMENT AND THERAPY 2021; 15:3773-3781. [PMID: 34522083 PMCID: PMC8434828 DOI: 10.2147/dddt.s322393] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 08/19/2021] [Indexed: 12/17/2022]
Abstract
Bacterial infections are predominantly treated with antibiotics, and resistance to antibiotics is becoming an increasing threat to our health. Pore-forming toxins (PFTs) are virulence factors secreted by many pathogenic bacterial strains, both in acute and chronic infections. They are special membrane-targeting proteins that exert toxic effects by forming pores in the cell membrane. Recent studies have elucidated the structure of PFTs and the detailed molecular mechanisms of their pathogenicity. Here, we discuss recent findings that highlight the regulatory mechanisms and important roles of two types of PFTs, α-PFTs and β-PFTs, in mediating the virulence of bacteria, and the therapeutic potential of targeting PFTs for antibacterial treatment. Therapeutic strategies based on PFTs are highly specific and may alleviate the issue of increasing resistance to antibiotics.
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Affiliation(s)
- Haijie Hu
- Institute of Biomedical Sciences, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, College of Life Sciences, Shandong Normal University, Jinan, 250014, People's Republic of China
| | - Min Liu
- Institute of Biomedical Sciences, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, College of Life Sciences, Shandong Normal University, Jinan, 250014, People's Republic of China
| | - Shuang Sun
- Institute of Biomedical Sciences, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, College of Life Sciences, Shandong Normal University, Jinan, 250014, People's Republic of China
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16
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Mohan R, Venugopal S. Molecular Binding and Simulation Studies of Staphylococcus aureus Superantigens with Flavonoid Compounds. Infect Disord Drug Targets 2021; 20:531-542. [PMID: 30727923 DOI: 10.2174/1871526519666190207092307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 01/02/2019] [Accepted: 02/01/2019] [Indexed: 12/29/2022]
Abstract
BACKGROUND Superantigens of Staphylococcus aureus namely enterotoxin A, exfoliative toxin A, and Toxic shock syndrome toxin-1 cause detrimental effects on the cells of the immune system. METHODS In this work, the toxins were downloaded from the Protein DataBank database and energies were minimized using KoBaMIN server. Forty flavonoids compounds were identified by pubchem compound database through extensive literature study and their 3D structures were obtained by submitting SMILES to CORINA tool. Based on Lipinski's rule of five, the molecules were filtered that resulted in 27 compounds. Molecular docking was performed for identifying the binding and interaction sites of flavonoids with the toxins using Autodock 4. RESULTS AND CONCLUSION The docked complexes were then subjected to molecular dynamics simulation using Gromacs. The analysis revealed the stability of the complexes as indicated by three hydrogen bonds formed during the simulation time period of 20 ns.
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Affiliation(s)
- Ramadevi Mohan
- Department of Integrative Biology, School of Biosciences and Technology, VIT, Vellore, Tamil nadu, 632 014, India
| | - Subhashree Venugopal
- Department of Integrative Biology, School of Biosciences and Technology, VIT, Vellore, Tamil nadu, 632 014, India
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17
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Venkatasamy V, Durairaj R, Karuppaiah P, Sridhar A, Kamaraj SK, Ramasamy T. An In Silico Evaluation of Molecular Interaction Between Antimicrobial Peptide Subtilosin A of Bacillus subtilis with Virulent Proteins of Aeromonas hydrophila. Int J Pept Res Ther 2021. [DOI: 10.1007/s10989-021-10203-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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18
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Wang G, Gao Y, Xu X, Zhang P, Wang J, Li G, Lv Q, Niu X, Liu H. Mode of action and structural modelling of the interaction of formononetin with suilysin. J Appl Microbiol 2021; 131:2010-2018. [PMID: 33639036 DOI: 10.1111/jam.15051] [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: 10/28/2020] [Revised: 02/02/2021] [Accepted: 02/17/2021] [Indexed: 11/28/2022]
Abstract
AIMS Suilysin is a critical pore-forming virulence factor of Streptococcus suis that has been demonstrated to substantially contribute to its pathogenicity. We have demonstrated that formononetin alleviates S. suis infection both in vivo and in vitro by targeting suilysin. However, the molecular mechanism of the effect is unclear. Our aim was to determine the molecular mechanism of the effect of formononetin on suilysin. METHODS AND RESULTS The mechanism of interaction between formononetin and suilysin was investigated by molecular modelling. The results indicated that formononetin was bound at the junction of domain two and domain four of suilysin. The binding free energy values indicated that the A415, Y412, E414, N413, T61, T62 and G416 residues are critical for this binding, this observation was confirmed by the changes in the flexibility of these residues and the distances between these residues and formononetin. The inhibitory effect of formononetin on the pore-forming activity of suilysin, binding constant and binding free energy were significantly decreased by site-specific mutagenesis of Y412 and N413. Finally, we analysed the spatial configuration of suilysin before and after formononetin binding, the results indicated that the binding changed the conformation of suilysin, especially the angle between domain two and domain four, resulting in the disruption of cholesterol binding to suilysin and in the loss of pore-forming activity. CONCLUSIONS Formononetin is located at the junction of domain two and domain four of suilysin, and Y412 and N413 play critical roles in the binding. Formononetin binding changes the angle between domain two and domain four of suilysin, resulting in the loss of the pore-inducing activity of suilysin. SIGNIFICANCE AND IMPACT OF THE STUDY This work will promote the application of formononetin to combat S. suis infections and may contribute to the development of new inhibitors or modification of existing inhibitors.
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Affiliation(s)
- G Wang
- Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, PR China.,College of Food Engineering, Jilin Engineering Normal University, Changchun, China.,College of Veterinary Medicine, Jilin University, Changchun, China
| | - Y Gao
- Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, PR China.,College of Veterinary Medicine, Jilin University, Changchun, China
| | - X Xu
- Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, PR China.,College of Veterinary Medicine, Jilin University, Changchun, China
| | - P Zhang
- College of Food Engineering, Jilin Engineering Normal University, Changchun, China
| | - J Wang
- Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, PR China.,College of Veterinary Medicine, Jilin University, Changchun, China
| | - G Li
- College of Veterinary Medicine, Jilin University, Changchun, China
| | - Q Lv
- Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, PR China.,College of Veterinary Medicine, Jilin University, Changchun, China
| | - X Niu
- College of Veterinary Medicine, Jilin University, Changchun, China
| | - H Liu
- Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, PR China
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19
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Li Y, Li Y, Mengist HM, Shi C, Zhang C, Wang B, Li T, Huang Y, Xu Y, Jin T. Structural Basis of the Pore-Forming Toxin/Membrane Interaction. Toxins (Basel) 2021; 13:toxins13020128. [PMID: 33572271 PMCID: PMC7914777 DOI: 10.3390/toxins13020128] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 01/13/2021] [Accepted: 02/02/2021] [Indexed: 12/14/2022] Open
Abstract
With the rapid growth of antibiotic-resistant bacteria, it is urgent to develop alternative therapeutic strategies. Pore-forming toxins (PFTs) belong to the largest family of virulence factors of many pathogenic bacteria and constitute the most characterized classes of pore-forming proteins (PFPs). Recent studies revealed the structural basis of several PFTs, both as soluble monomers, and transmembrane oligomers. Upon interacting with host cells, the soluble monomer of bacterial PFTs assembles into transmembrane oligomeric complexes that insert into membranes and affect target cell-membrane permeability, leading to diverse cellular responses and outcomes. Herein we have reviewed the structural basis of pore formation and interaction of PFTs with the host cell membrane, which could add valuable contributions in comprehensive understanding of PFTs and searching for novel therapeutic strategies targeting PFTs and interaction with host receptors in the fight of bacterial antibiotic-resistance.
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Affiliation(s)
- Yajuan Li
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China; (Y.L.); (C.S.); (B.W.); (T.L.); (Y.H.)
| | - Yuelong Li
- Hefei National Laboratory for Physical Sciences at Microscale, Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, School of Basic Medical Sciences, University of Science and Technology of China, Hefei 230027, China; (Y.L.); (H.M.M.); (C.Z.)
| | - Hylemariam Mihiretie Mengist
- Hefei National Laboratory for Physical Sciences at Microscale, Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, School of Basic Medical Sciences, University of Science and Technology of China, Hefei 230027, China; (Y.L.); (H.M.M.); (C.Z.)
| | - Cuixiao Shi
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China; (Y.L.); (C.S.); (B.W.); (T.L.); (Y.H.)
| | - Caiying Zhang
- Hefei National Laboratory for Physical Sciences at Microscale, Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, School of Basic Medical Sciences, University of Science and Technology of China, Hefei 230027, China; (Y.L.); (H.M.M.); (C.Z.)
| | - Bo Wang
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China; (Y.L.); (C.S.); (B.W.); (T.L.); (Y.H.)
| | - Tingting Li
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China; (Y.L.); (C.S.); (B.W.); (T.L.); (Y.H.)
| | - Ying Huang
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China; (Y.L.); (C.S.); (B.W.); (T.L.); (Y.H.)
| | - Yuanhong Xu
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China; (Y.L.); (C.S.); (B.W.); (T.L.); (Y.H.)
- Correspondence: (Y.X.); (T.J.); Tel.: +86-13505694447 (Y.X.); +86-17605607323 (T.J.)
| | - Tengchuan Jin
- Hefei National Laboratory for Physical Sciences at Microscale, Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, School of Basic Medical Sciences, University of Science and Technology of China, Hefei 230027, China; (Y.L.); (H.M.M.); (C.Z.)
- Correspondence: (Y.X.); (T.J.); Tel.: +86-13505694447 (Y.X.); +86-17605607323 (T.J.)
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20
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Yang Y, Wang X, Gao Y, Wang H, Niu X. Insight into the Dual inhibitory Mechanism of verbascoside targeting serine/threonine phosphatase Stp1 against Staphylococcus aureus. Eur J Pharm Sci 2021; 157:105628. [PMID: 33115673 DOI: 10.1016/j.ejps.2020.105628] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 10/19/2020] [Accepted: 10/23/2020] [Indexed: 12/19/2022]
Abstract
The eukaryotic-like serine/threonine phosphatase (Stp1) is an enzyme-dependent protein phosphatase involved in regulating various virulence factors of Staphylococcus aureus. Owing to its role in S. aureus infections, Stp1 has become a potential target for antibiotic development. Unfortunately, there are very few reports describing Stp1 inhibitors. Using virtual screening, we have identified a potent and effective Stp1 inhibitor, verbascoside (VBS). Interestingly, the kinetics of the enzymatic reaction revealed that this natural inhibitor acts via both competitive and allosteric mechanisms. To explore the mechanism of interaction between VBS and Stp1, standard molecular dynamics (MD) simulations were performed for the Stp1-VBS complex. Consistent with the experimental results, competitive and allosteric binding sites for VBS were identified in Stp1. Met39, Gly41, His42, Arg161, and Asn162 residues were involved in the competitive binding of VBS, while Arg122, Ser136, Asp137, Asn142, and Val145 residues were associated with the allosteric binding of VBS. The contributions of these residues were confirmed by amino acid site-directed mutagenesis and fluorescence quenching experiments. This work demonstrates that VBS is a potent anti-virulence compound against S. aureus infection, laying the foundation for the further development of novel anti-virulence agents.
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Affiliation(s)
- Yanan Yang
- College of Food Science and Engineering, Jilin University, Changchun, China
| | - Xiyan 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.
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21
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Sathyanarayana P, Visweswariah SS, Ayappa KG. Mechanistic Insights into Pore Formation by an α-Pore Forming Toxin: Protein and Lipid Bilayer Interactions of Cytolysin A. Acc Chem Res 2021; 54:120-131. [PMID: 33291882 DOI: 10.1021/acs.accounts.0c00551] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Pore forming toxins (PFTs) are the largest class of bacterial toxins playing a central role in bacterial pathogenesis. They are proteins specifically designed to form nanochannels in the membranes of target cells, ultimately resulting in cell death and establishing infection. PFTs are broadly classified as α- and β-PFTs, depending on secondary structures that form the transmembrane channel. A unique feature about this class of proteins is the drastic conformational changes and complex oligomerization pathways that occur upon exposure to the plasma membrane. A molecular understanding of pore formation has implications in designing novel intervention strategies to combat rising antimicrobial resistance, targeted-cancer therapy, as well as designing nanopores for specialized technologies. Central to unraveling the pore formation pathway is the availability of high resolution crystal structures. In this regard, β-toxins are better understood, when compared with α-toxins whose pore forming mechanisms are complicated by an incomplete knowledge of the driving forces for amphiphatic membrane-inserted helices to organize into functional pores. With the publication of the first crystal structure for an α-toxin, cytolysin A (ClyA), in 2009 we embarked on an extensive multiscale study to unravel its pore forming mechanism. This Account represents the collective mechanistic knowledge gained in our laboratories using a variety of experimental and theoretical techniques which include large scale molecular dynamics (MD) simulations, kinetic modeling studies, single-molecule fluorescence imaging, and super-resolution spectroscopy. We reported MD simulations of the ClyA protomer, oligomeric intermediates, and full pore complex in a lipid bilayer and mapped the conformational transitions that accompany membrane binding. Using single-molecule fluorescence imaging, the conformational transition was experimentally verified by analysis of various diffusion states of membrane bound ClyA. Importantly, we have uncovered a hitherto unknown putative cholesterol binding motif in the membrane-inserted helix of ClyA. Distinct binding pockets for cholesterol formed by adjacent membrane-inserted helices are revealed in MD simulations. Cholesterol appears to play a dual role by stabilizing both the membrane-inserted protomer as well as oligomeric intermediates. Molecular dynamics simulations and kinetic modeling studies suggest that the membrane-inserted arcs oligomerize reversibly to form the predominant transmembrane oligomeric intermediates during pore formation. We posit that this mechanistic understanding of the complex action of α-PFTs has implications in unraveling pore assembly across the wider family of bacterial toxins. With emerging antimicrobial resistance, alternate therapies may rely on disrupting pore functionality or oligomerization of these pathogenic determinants utilized by bacteria, and our study includes assessing the potential for dendrimers as pore blockers.
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Affiliation(s)
- Pradeep Sathyanarayana
- Centre for BioSystems Science and Engineering, Indian Institute of Science, Bangalore, India 560012
| | - Sandhya S. Visweswariah
- Centre for BioSystems Science and Engineering, Indian Institute of Science, Bangalore, India 560012
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, India 560012
| | - K. Ganapathy Ayappa
- Centre for BioSystems Science and Engineering, Indian Institute of Science, Bangalore, India 560012
- Department of Chemical Engineering, Indian Institute of Science, Bangalore, India 560012
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22
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Wang G, Gao Y, Wu X, Gao X, Zhang M, Liu H, Fang T. Inhibitory Effect of Piceatannol on Streptococcus suis Infection Both in vitro and in vivo. Front Microbiol 2020; 11:593588. [PMID: 33329477 PMCID: PMC7728846 DOI: 10.3389/fmicb.2020.593588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/04/2020] [Indexed: 11/18/2022] Open
Abstract
Suilysin (SLY) plays a critical role in Streptococcus suis infections making it an ideal target to the combat infection caused by this pathogen. In the present study, we found that piceatannol (PN), a natural compound, inhibits pore-formation by blocking the oligomerization of SLY without affecting the growth of S. suis and the expression of SLY. Furthermore, PN alleviated the J774 cell damage and the expression of the inflammatory cytokine tumor necrosis factor-α (TNF-α) and interleukin-1α (IL-1β) induced by S. suis in vitro. The computational biology and biochemistry results indicated that PN binds to the joint region of D2 and D4 in SLY, and Asn57, Pro58, Pro59, Glu76, Ile379, Glu380, and Glu418 were critical residues involved in the binding. The binding effect between PN and SLY hindered the SLY monomers from forming the oligomers, thereby weakening the hemolytic activity of SLY. This mechanism was also verified by hemolysis analysis and analysis of KA formation after site-specific mutagenesis. Furthermore, PN protected mice from S. suis infections by reducing bacterial colony formation and the inflammatory response in target organs in vivo. These results indicate that PN is a feasible drug candidate to combat S. suis infections.
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Affiliation(s)
- Guizhen Wang
- Department of Respiratory Medicine, The First Hospital of Jilin University, Jilin University, Changchun, China.,College of Food Engineering, Jilin Engineering Normal University, Changchun, China.,Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Yawen Gao
- Department of Respiratory Medicine, The First Hospital of Jilin University, Jilin University, Changchun, China.,Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xiuhua Wu
- College of Food Engineering, Jilin Engineering Normal University, Changchun, China
| | - Xiue Gao
- College of Food Engineering, Jilin Engineering Normal University, Changchun, China
| | - Min Zhang
- College of Food Engineering, Jilin Engineering Normal University, Changchun, China
| | - Hongmei Liu
- Department of Respiratory Medicine, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Tianqi Fang
- Department of Respiratory Medicine, The First Hospital of Jilin University, Jilin University, Changchun, China.,Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
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23
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Guzzo F, Scognamiglio M, Fiorentino A, Buommino E, D’Abrosca B. Plant Derived Natural Products against Pseudomonas aeruginosa and Staphylococcus aureus: Antibiofilm Activity and Molecular Mechanisms. Molecules 2020; 25:E5024. [PMID: 33138250 PMCID: PMC7663672 DOI: 10.3390/molecules25215024] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/24/2020] [Accepted: 10/27/2020] [Indexed: 12/13/2022] Open
Abstract
Bacteria are social organisms able to build complex structures, such as biofilms, that are highly organized surface-associated communities of microorganisms, encased within a self- produced extracellular matrix. Biofilm is commonly associated with many health problems since its formation increases resistance to antibiotics and antimicrobial agents, as in the case of Pseudomonas aeruginosa and Staphylococcus aureus, two human pathogens causing major concern. P. aeruginosa is responsible for severe nosocomial infections, the most frequent of which is ventilator-associated pneumonia, while S. aureus causes several problems, like skin infections, septic arthritis, and endocarditis, to name just a few. Literature data suggest that natural products from plants, bacteria, fungi, and marine organisms have proven to be effective as anti-biofilm agents, inhibiting the formation of the polymer matrix, suppressing cell adhesion and attachment, and decreasing the virulence factors' production, thereby blocking the quorum sensing network. Here, we focus on plant derived chemicals, and provide an updated literature review on the anti-biofilm properties of terpenes, flavonoids, alkaloids, and phenolic compounds. Moreover, whenever information is available, we also report the mechanisms of action.
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Affiliation(s)
- Francesca Guzzo
- Dipartimento di Scienze e Tecnologie Ambientali Biologiche e Farmaceutiche–DiSTABiF, Università degli Studi della Campania “Luigi Vanvitelli”, via Vivaldi 43, I-81100 Caserta, Italy; (F.G.); (M.S.); (A.F.)
| | - Monica Scognamiglio
- Dipartimento di Scienze e Tecnologie Ambientali Biologiche e Farmaceutiche–DiSTABiF, Università degli Studi della Campania “Luigi Vanvitelli”, via Vivaldi 43, I-81100 Caserta, Italy; (F.G.); (M.S.); (A.F.)
| | - Antonio Fiorentino
- Dipartimento di Scienze e Tecnologie Ambientali Biologiche e Farmaceutiche–DiSTABiF, Università degli Studi della Campania “Luigi Vanvitelli”, via Vivaldi 43, I-81100 Caserta, Italy; (F.G.); (M.S.); (A.F.)
- Dipartimento di Biotecnologia Marina, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
| | - Elisabetta Buommino
- Dipartimento di Farmacia, Università degli Studi di Napoli “Federico II”, Via Domenico Montesano 49, 80131 Napoli, Italy;
| | - Brigida D’Abrosca
- Dipartimento di Scienze e Tecnologie Ambientali Biologiche e Farmaceutiche–DiSTABiF, Università degli Studi della Campania “Luigi Vanvitelli”, via Vivaldi 43, I-81100 Caserta, Italy; (F.G.); (M.S.); (A.F.)
- Dipartimento di Biotecnologia Marina, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
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Marchetti M, De Bei O, Bettati S, Campanini B, Kovachka S, Gianquinto E, Spyrakis F, Ronda L. Iron Metabolism at the Interface between Host and Pathogen: From Nutritional Immunity to Antibacterial Development. Int J Mol Sci 2020; 21:E2145. [PMID: 32245010 PMCID: PMC7139808 DOI: 10.3390/ijms21062145] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 03/16/2020] [Accepted: 03/17/2020] [Indexed: 02/08/2023] Open
Abstract
Nutritional immunity is a form of innate immunity widespread in both vertebrates and invertebrates. The term refers to a rich repertoire of mechanisms set up by the host to inhibit bacterial proliferation by sequestering trace minerals (mainly iron, but also zinc and manganese). This strategy, selected by evolution, represents an effective front-line defense against pathogens and has thus inspired the exploitation of iron restriction in the development of innovative antimicrobials or enhancers of antimicrobial therapy. This review focuses on the mechanisms of nutritional immunity, the strategies adopted by opportunistic human pathogen Staphylococcus aureus to circumvent it, and the impact of deletion mutants on the fitness, infectivity, and persistence inside the host. This information finally converges in an overview of the current development of inhibitors targeting the different stages of iron uptake, an as-yet unexploited target in the field of antistaphylococcal drug discovery.
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Affiliation(s)
- Marialaura Marchetti
- Interdepartmental Center Biopharmanet-TEC, University of Parma, 43124 Parma, Italy; (M.M.); (S.B.)
| | - Omar De Bei
- Department of Food and Drug, University of Parma, 43124 Parma, Italy; (O.D.B.); (B.C.)
| | - Stefano Bettati
- Interdepartmental Center Biopharmanet-TEC, University of Parma, 43124 Parma, Italy; (M.M.); (S.B.)
- Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy
- Institute of Biophysics, National Research Council, 56124 Pisa, Italy
- National Institute of Biostructures and Biosystems, 00136 Rome, Italy
| | - Barbara Campanini
- Department of Food and Drug, University of Parma, 43124 Parma, Italy; (O.D.B.); (B.C.)
| | - Sandra Kovachka
- Department of Drug Science and Technology, University of Turin, 10125 Turin, Italy; (S.K.); (E.G.); (F.S.)
| | - Eleonora Gianquinto
- Department of Drug Science and Technology, University of Turin, 10125 Turin, Italy; (S.K.); (E.G.); (F.S.)
| | - Francesca Spyrakis
- Department of Drug Science and Technology, University of Turin, 10125 Turin, Italy; (S.K.); (E.G.); (F.S.)
| | - Luca Ronda
- Interdepartmental Center Biopharmanet-TEC, University of Parma, 43124 Parma, Italy; (M.M.); (S.B.)
- Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy
- Institute of Biophysics, National Research Council, 56124 Pisa, Italy
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25
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Fox D, Mathur A, Xue Y, Liu Y, Tan WH, Feng S, Pandey A, Ngo C, Hayward JA, Atmosukarto II, Price JD, Johnson MD, Jessberger N, Robertson AAB, Burgio G, Tscharke DC, Fox EM, Leyton DL, Kaakoush NO, Märtlbauer E, Leppla SH, Man SM. Bacillus cereus non-haemolytic enterotoxin activates the NLRP3 inflammasome. Nat Commun 2020; 11:760. [PMID: 32029733 PMCID: PMC7005308 DOI: 10.1038/s41467-020-14534-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2019] [Accepted: 01/14/2020] [Indexed: 02/07/2023] Open
Abstract
Inflammasomes are important for host defence against pathogens and homeostasis with commensal microbes. Here, we show non-haemolytic enterotoxin (NHE) from the neglected human foodborne pathogen Bacillus cereus is an activator of the NLRP3 inflammasome and pyroptosis. NHE is a non-redundant toxin to haemolysin BL (HBL) despite having a similar mechanism of action. Via a putative transmembrane region, subunit C of NHE initiates binding to the plasma membrane, leading to the recruitment of subunit B and subunit A, thus forming a tripartite lytic pore that is permissive to efflux of potassium. NHE mediates killing of cells from multiple lineages and hosts, highlighting a versatile functional repertoire in different host species. These data indicate that NHE and HBL operate synergistically to induce inflammation and show that multiple virulence factors from the same pathogen with conserved function and mechanism of action can be exploited for sensing by a single inflammasome.
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Affiliation(s)
- Daniel Fox
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Anukriti Mathur
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Yansong Xue
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Yunqi Liu
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Wei Hong Tan
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Shouya Feng
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Abhimanu Pandey
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Chinh Ngo
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Jenni A Hayward
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Ines I Atmosukarto
- Lipotek Pty Ltd. The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Jason D Price
- Lipotek Pty Ltd. The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Matthew D Johnson
- Research School of Biology, The Australian National University, Canberra, Australia
| | - Nadja Jessberger
- Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität München, Oberschleißheim, Germany
| | - Avril A B Robertson
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Gaetan Burgio
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - David C Tscharke
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Edward M Fox
- Department of Applied Sciences, Northumbria University, Newcastle Upon Tyne, UK
| | - Denisse L Leyton
- Research School of Biology, The Australian National University, Canberra, Australia.,Medical School, The Australian National University, Canberra, Australia
| | - Nadeem O Kaakoush
- School of Medical Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia
| | - Erwin Märtlbauer
- Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität München, Oberschleißheim, Germany
| | - Stephen H Leppla
- Microbial Pathogenesis Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Si Ming Man
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia.
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26
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Liu S, Zhang J, Zhou Y, Hu N, Li J, Wang Y, Niu X, Deng X, Wang J. Pterostilbene restores carbapenem susceptibility in New Delhi metallo-β-lactamase-producing isolates by inhibiting the activity of New Delhi metallo-β-lactamases. Br J Pharmacol 2019; 176:4548-4557. [PMID: 31376166 DOI: 10.1111/bph.14818] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 07/19/2019] [Accepted: 07/22/2019] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE Bacteria producing New Delhi metallo-β-lactamase-1 (NDM-1) are an increasing clinical threat. NDM-1 can inactivate almost all β-lactams and is not sensitive to any existing β-lactamase inhibitors. To identify effective inhibitors of the NDM-1 enzyme and clarify the mechanism of action, a "lead compound" for developing more potent NDM-1 inhibitors needs to be provided. EXPERIMENTAL APPROACH Natural compounds were tested by enzyme inhibition screening to find potential inhibitors. MIC assays, growth curve assays, and time-kill assays were conducted to evaluate the in vitro antibacterial activity of pterostilbene and the combination of pterostilbene and meropenem. A murine thigh model and a mouse pneumonia model were used to evaluate the in vivo efficacy of combined therapy. Molecular modelling and a mutational analysis were used to clarify the mechanism of action. KEY RESULTS Pterostilbene significantly inhibited NDM-1 hydrolysis activity in enzyme inhibition screening assays and effectively restored the effectiveness of meropenem in vitro with NDM-expressing isolates in antibacterial activity assays. In addition, the combined therapy effectively reduced the bacterial burden in a murine thigh model and protected mice from pneumonia caused by Klebsiella pneumoniae. By means of molecular dynamics simulation, we observed that pterostilbene localized to the catalytic pocket of NDM-1, hindering substrate binding to NDM-1 and reducing NDM-1 activity. CONCLUSIONS AND IMPLICATIONS These findings indicated that pterostilbene combined with meropenem may offer a new safe and potential "lead compound" for the further development of NDM-1 inhibitors.
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Affiliation(s)
- Shui Liu
- Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jian Zhang
- Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Yonglin Zhou
- Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Naiyu Hu
- College of Animal Sciences, Jilin University, Changchun, China
| | - Jiyun Li
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Yang Wang
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Xiaodi Niu
- College of Food Science and Engineering, Jilin University, Changchun, China
| | - Xuming Deng
- Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jianfeng Wang
- Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
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27
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Wu SC, Liu F, Zhu K, Shen JZ. Natural Products That Target Virulence Factors in Antibiotic-Resistant Staphylococcus aureus. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:13195-13211. [PMID: 31702908 DOI: 10.1021/acs.jafc.9b05595] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The increase in the incidence of antibiotic-resistant Staphylococcus aureus (S. aureus) associated infections necessitates the urgent development of novel therapeutic strategies and antibacterial drugs. Antivirulence strategy is an especially compelling alternative strategy due to its low selective pressure for the development of drug resistance in bacteria. Plants and microorganisms are not only important food and medicinal resources but also serve as sources for the discovery of natural products that target bacterial virulence factors. This review discusses the mechanisms of the major virulence factors of S. aureus, including the accessory gene regulator quorum-sensing system, bacterial biofilm formation, α-hemolysin, sortase A, and staphyloxanthin. We also provide an overview of natural products isolated from plants and microorganisms with activity against the major virulence factors of S. aureus and their adjuvant effects on existing antibiotics to overcome antibiotic-resistant S. aureus. Finally, the limitations and solutions of these antivirulence compounds are discussed, which will help in the development of novel antibacterial drugs against antibiotic-resistant S. aureus.
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Affiliation(s)
- Shuai-Cheng Wu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine , China Agricultural University , No. 2 Yuanmingyuan West Road , Beijing 100193 , People's Republic of China
- College of Veterinary Medicine , Qingdao Agricultural University , No. 700 Changcheng Road , Qingdao , Shandong 266109 , People's Republic of China
| | - Fei Liu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine , China Agricultural University , No. 2 Yuanmingyuan West Road , Beijing 100193 , People's Republic of China
| | - Kui Zhu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine , China Agricultural University , No. 2 Yuanmingyuan West Road , Beijing 100193 , People's Republic of China
| | - Jian-Zhong Shen
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine , China Agricultural University , No. 2 Yuanmingyuan West Road , Beijing 100193 , People's Republic of China
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28
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Staphylococcus aureus Toxins: From Their Pathogenic Roles to Anti-virulence Therapy Using Natural Products. BIOTECHNOL BIOPROC E 2019. [DOI: 10.1007/s12257-019-0059-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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29
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Wang L, Li B, Si X, Liu X, Deng X, Niu X, Jin Y, Wang D, Wang J. Quercetin protects rats from catheter-related Staphylococcus aureus infections by inhibiting coagulase activity. J Cell Mol Med 2019; 23:4808-4818. [PMID: 31094081 PMCID: PMC6584481 DOI: 10.1111/jcmm.14371] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 03/18/2019] [Accepted: 04/22/2019] [Indexed: 11/30/2022] Open
Abstract
Coagulase (Coa) activity is essential for the virulence of Staphylococcus aureus (S aureus), one of the most important pathogenic bacteria leading to catheter‐related bloodstream infections (CRBSI). We have demonstrated that the mutation of coagulase improved outcomes in disease models of S aureus CRBSI, suggesting that targeting Coa may represent a novel antiinfective strategy for CRBSI. Here, we found that quercetin, a natural compound that does not affect S aureus viability, could inhibit Coa activity. Chemical biological analysis revealed that the direct engagement of quercetin with the active site (residues Tyr187, Leu221 and His228) of Coa inhibited its activity. Furthermore, treatment with quercetin reduced the retention of bacteria on catheter surfaces, decreased the bacterial load in the kidneys and alleviated kidney abscesses in vivo. These data suggest that antiinfective therapy targeting Coa with quercetin may represent a novel strategy and provide a new leading compound with which to combat bacterial infections.
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Affiliation(s)
- Lin Wang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - BangBang Li
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China.,College of Animal Science, Jilin University, Changchun, Jilin, China.,The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Xiaosa Si
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Xingyuan Liu
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Xuming Deng
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Xiaodi Niu
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
| | - Yingli Jin
- Department of Pharmacology, College of Basic Medical Science, Jilin University, Changchun, Jilin, China
| | - Dacheng Wang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China.,College of Animal Science, Jilin University, Changchun, Jilin, China
| | - Jianfeng Wang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China
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30
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Jiang L, Yi T, Shen Z, Teng Z, Wang J. Aloe-emodin Attenuates Staphylococcus aureus Pathogenicity by Interfering With the Oligomerization of α-Toxin. Front Cell Infect Microbiol 2019; 9:157. [PMID: 31157174 PMCID: PMC6530610 DOI: 10.3389/fcimb.2019.00157] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 04/26/2019] [Indexed: 01/30/2023] Open
Abstract
α-toxin, an essential virulence factor secreted by Staphylococcus aureus (S. aureus), is a critical exotoxin in multiple infections. In this study, we found that aloe-emodin (AE), a natural compound lacking anti-S. aureus activity, could inhibit the hemolytic activity of α-toxin. Oligomerization assays, molecular dynamics simulations, and fluorescence-quenching analyses were used to determine the mechanism of this inhibition. The oligomerization of α-toxin was restricted by the engagement of AE with K110, T112, and M113 of the toxin, which eventually resulted in inhibition of the hemolytic activity. Lactate dehydrogenase and live/dead assays demonstrated that AE decreased the injury of human lung epithelial cells (A549) and mouse lung macrophages (MH-S) mediated by S. aureus. Furthermore, treatment with AE showed robust protective effects in mice infected by S. aureus. These findings suggest that AE effectively inhibited the pore-forming activity of α-toxin and showed a protective effect against S. aureus virulence in vitro and in vivo, which may provide a new strategy and new antibacterial agent for clinical treatment of S. aureus infections.
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Affiliation(s)
- Lanxiang Jiang
- Department of Dermatology, Second Hospital of Jilin University, Jilin University, Changchun, China
| | - Tian Yi
- Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Animal Science, Jilin University, Changchun, China
| | - Ziying Shen
- Laboratory Animal Center, College of Animal Sciences, Jilin University, Changchun, China
| | - Zihao Teng
- Department of Dermatology, Second Hospital of Jilin University, Jilin University, Changchun, China
| | - Jianfeng Wang
- Department of Dermatology, Second Hospital of Jilin University, Jilin University, Changchun, China.,Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Animal Science, Jilin University, Changchun, China
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31
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Lin SJ, Chen YF, Hsu KC, Chen YL, Ko TP, Lo CF, Wang HC, Wang HC. Structural Insights to the Heterotetrameric Interaction between the Vibrio parahaemolyticus PirA vp and PirB vp Toxins and Activation of the Cry-Like Pore-Forming Domain. Toxins (Basel) 2019; 11:toxins11040233. [PMID: 31013623 PMCID: PMC6520838 DOI: 10.3390/toxins11040233] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 04/16/2019] [Accepted: 04/19/2019] [Indexed: 02/06/2023] Open
Abstract
Acute hepatopancreatic necrosis disease (AHPND) is a newly emergent penaeid shrimp disease which can cause 70-100% mortality in Penaeus vannamei and Penaeus monodon, and has resulted in enormous economic losses since its appearance. AHPND is caused by the specific strains of Vibrio parahaemolyticus that harbor the pVA1 plasmid and express PirAvp and PirBvp toxins. These two toxins have been reported to form a binary complex. When both are present, they lead to the death of shrimp epithelial cells in the hepatopancreas and cause the typical histological symptoms of AHPND. However, the binding mode of PirAvp and PirBvp has not yet been determined. Here, we used isothermal titration calorimetry (ITC) to measure the binding affinity of PirAvp and PirBvp. Since the dissociation constant (Kd = 7.33 ± 1.20 μM) was considered too low to form a sufficiently stable complex for X-ray crystallographic analysis, we used alternative methods to investigate PirAvp-PirBvp interaction, first by using gel filtration to evaluate the molecular weight of the PirAvp/PirBvp complex, and then by using cross-linking and hydrogen-deuterium exchange (HDX) mass spectrometry to further understand the interaction interface between PirAvp and PirBvp. Based on these results, we propose a heterotetrameric interaction model of this binary toxin complex. This model provides insight of how conformational changes might activate the PirBvp N-terminal pore-forming domain and should be helpful for devising effective anti-AHPND strategies in the future.
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Affiliation(s)
- Shin-Jen Lin
- Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan 701, Taiwan.
| | - Yi-Fan Chen
- The Ph.D. Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei 110, Taiwan.
- Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
| | - Kai-Cheng Hsu
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
- Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
- Biomedical Commercialization Center, Taipei Medical University, Taipei 110, Taiwan.
| | - Yun-Ling Chen
- Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan 701, Taiwan.
| | - Tzu-Ping Ko
- Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan.
| | - Chu-Fang Lo
- Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan 701, Taiwan.
- International Center for the Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan 701, Taiwan.
| | - Han-Ching Wang
- Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan 701, Taiwan.
- International Center for the Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan 701, Taiwan.
| | - Hao-Ching Wang
- The Ph.D. Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei 110, Taiwan.
- Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
- International Center for the Scientific Development of Shrimp Aquaculture, National Cheng Kung University, Tainan 701, Taiwan.
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32
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Zhou Y, Wang J, Guo Y, Liu X, Liu S, Niu X, Wang Y, Deng X. Discovery of a potential MCR-1 inhibitor that reverses polymyxin activity against clinical mcr-1-positive Enterobacteriaceae. J Infect 2019; 78:364-372. [PMID: 30851289 DOI: 10.1016/j.jinf.2019.03.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 02/26/2019] [Accepted: 03/03/2019] [Indexed: 11/20/2022]
Abstract
The recent emergence of the plasmid-mediated colistin resistance gene mcr-1 poses a substantial clinical threat to the severe infections caused by CRE (Carbapenem Resistant Enterobacteriaceae), as the treatment failure of the mcr-1-positive CRE "Superbug" most likely occurs by using the combination of carbapenem and polymixins. Therefore, our study aims to seek a potent MCR-1 inhibitor to fight this infection. A checkerboard MIC (Minimum Inhibitory Concentration) assay, time-killing assay, MPNP (Modified rapid polymyxin Nordmann/Poirel) test, combined disk test and molecular modelling analysis were performed on different mcr-1-positive strains to confirm the synergistic effects of the combination of colistin and osthole (OST). And a thigh mouse infection model was also used to evaluate such synergies. We identified that OST regained the bactericidal activity of polymyxins (FIC (Fractional Inhibitory Concentration) index = 0.11±0.04 - 0.29±0.10) against mcr-1-positive Enterobacteriaceae including Escherichia coli and Klebsiella pneumoniae. The in-vitro time-killing assays showed that either OST or polymyxins failed to eradicate mcr-1-positive Enterobacteriaceae, but the combination eliminated mcr-1-positive Enterobacteriaceae by 3-7-h post-inoculation. The mouse infection model demonstrated that the combination therapy significantly reduced the bacterial load in the thighs following subcutaneous administration. Our results established that OST is a promising natural compound that could be used to extend the life of polymyxins and to tackle the inevitability of serious infections caused by polymyxin-resistant bacteria.
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Affiliation(s)
- Yonglin Zhou
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jianfeng Wang
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Yan Guo
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xingqi Liu
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Shunli Liu
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xiaodi Niu
- Department of Food Quality and Safety, Jilin University, Changchun, China
| | - Yang Wang
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, China.
| | - Xuming Deng
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China.
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33
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Divyakolu S, Chikkala R, Ratnakar KS, Sritharan V. Hemolysins of <i>Staphylococcus aureus</i>—An Update on Their Biology, Role in Pathogenesis and as Targets for Anti-Virulence Therapy. ACTA ACUST UNITED AC 2019. [DOI: 10.4236/aid.2019.92007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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34
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Pharmacological Targeting of Pore-Forming Toxins as Adjunctive Therapy for Invasive Bacterial Infection. Toxins (Basel) 2018; 10:toxins10120542. [PMID: 30562923 PMCID: PMC6316385 DOI: 10.3390/toxins10120542] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 12/10/2018] [Accepted: 12/14/2018] [Indexed: 12/23/2022] Open
Abstract
For many of the most important human bacterial infections, invasive disease severity is fueled by the cell damaging and pro-inflammatory effects of secreted pore-forming toxins (PFTs). Isogenic PFT-knockout mutants, e.g., Staphylococcus aureus lacking α-toxin or Streptococcus pneumoniae deficient in pneumolysin, show attenuation in animal infection models. This knowledge has inspired multi-model investigations of strategies to neutralize PFTs or counteract their toxicity as a novel pharmacological approach to ameliorate disease pathogenesis in clinical disease. Promising examples of small molecule, antibody or nanotherapeutic drug candidates that directly bind and neutralize PFTs, block their oligomerization or membrane receptor interactions, plug establishment membrane pores, or boost host cell resiliency to withstand PFT action have emerged. The present review highlights these new concepts, with a special focus on β-PFTs produced by leading invasive human Gram-positive bacterial pathogens. Such anti-virulence therapies could be applied as an adjunctive therapy to antibiotic-sensitive and -resistant strains alike, and further could be free of deleterious effects that deplete the normal microflora.
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Liu S, Zhou Y, Niu X, Wang T, Li J, Liu Z, Wang J, Tang S, Wang Y, Deng X. Magnolol restores the activity of meropenem against NDM-1-producing Escherichia coli by inhibiting the activity of metallo-beta-lactamase. Cell Death Discov 2018; 4:28. [PMID: 29531825 PMCID: PMC5841300 DOI: 10.1038/s41420-018-0029-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 12/22/2017] [Indexed: 01/23/2023] Open
Abstract
The emergence of plasmid-mediated New Delhi metallo-β-lactamase-1 (NDM-1) in carbapenem-resistant Gram-negative pathogens is an increasing clinical threat. Here we report the discovery of an NDM-1 inhibitor, magnolol, through enzyme inhibition screening. We showed that magnolol significantly inhibited NDM enzyme activity (IC50 = 6.47 µg/mL), and it restored the activity of meropenem against Escherichia coli ZC-YN3, an NDM-1-producing E. coli isolate, in in vitro antibacterial activity assays. Magnolol lacked direct antibacterial activity, but compared with meropenem alone, it reduced the MICs of meropenem against E. coli ZC-YN3 by 4-fold and killed almost all the bacteria within 3 h. Molecular modeling and a mutational analysis demonstrated that magnolol binds directly to the catalytic pocket (residues 110 to 200) of NDM-1, thereby blocking the binding of the substrate to NDM-1 and leading to its inactivation. Our results demonstrate that the combination of magnolol and meropenem may have the potential to treat infections caused by NDM-1-positive, carbapenem-resistant Gram-negative pathogens.
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Affiliation(s)
- Shui Liu
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Yonglin Zhou
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xiaodi Niu
- Department of Food Quality and Safety, Jilin University, Changchun, China
| | - Tingting Wang
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jiyun Li
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Zhongjie Liu
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Jianfeng Wang
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Shusheng Tang
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Yang Wang
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Xuming Deng
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
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Dong J, Liu Y, Xu N, Yang Q, Ai X. Morin Protects Channel Catfish From Aeromonas hydrophila Infection by Blocking Aerolysin Activity. Front Microbiol 2018; 9:2828. [PMID: 30519232 PMCID: PMC6258893 DOI: 10.3389/fmicb.2018.02828] [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: 09/11/2018] [Accepted: 11/05/2018] [Indexed: 11/13/2022] Open
Abstract
Aeromonas hydrophila (A. hydrophila) is an opportunistic bacterial pathogen widely distributed in the environments, particular aquatic environment. The pathogen can cause a range of infections in both human and animals including fishes. However, the application of antibiotics in treatment of A. hydrophila infections leads to the emergence of resistant strains. Consequently, new approaches need to be developed in fighting this pathogen. Aerolysin, the chief virulence factor produced by pathogenic A. hydrophila strains has been employed as target identifying new drugs. In our present study, we found that morin, a flavonoid without anti-bacterial activity isolated from traditional Chinese medicine, could directly inhibit the hemolytic activity of aerolysin. To determine the binding sites and the action of mechanism of morin against AerA, several assays were performed. Ser36, Pro347, and Arg356 were identified as the main binding sites affecting the conformation of AerA and resulted in block of the heptameric formation. Moreover, morin could protect Vero cells from cell injury mediated by aerolysin. In vivo study showed that morin could provide a protection to channel catfish against A. hydrophila infection. These results demonstrated that morin could be developed as a promising candidate for the treatment of A. hydrophila infections by decreasing the pathogenesis of A. hydrophila.
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Affiliation(s)
- Jing Dong
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China.,Key Laboratory of Control of Quality and Safety for Aquatic Products, Ministry of Agriculture, Beijing, China
| | - Yongtao Liu
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China.,Key Laboratory of Control of Quality and Safety for Aquatic Products, Ministry of Agriculture, Beijing, China
| | - Ning Xu
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China.,Key Laboratory of Control of Quality and Safety for Aquatic Products, Ministry of Agriculture, Beijing, China
| | - Qiuhong Yang
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China.,Key Laboratory of Control of Quality and Safety for Aquatic Products, Ministry of Agriculture, Beijing, China
| | - Xiaohui Ai
- Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, China.,Key Laboratory of Control of Quality and Safety for Aquatic Products, Ministry of Agriculture, Beijing, China
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Bulagonda EP, Manivannan B, Mahalingam N, Lama M, Chanakya PP, Khamari B, Jadhao S, Vasudevan M, Nagaraja V. Comparative genomic analysis of a naturally competent Elizabethkingia anophelis isolated from an eye infection. Sci Rep 2018; 8:8447. [PMID: 29855598 PMCID: PMC5981450 DOI: 10.1038/s41598-018-26874-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 05/17/2018] [Indexed: 01/18/2023] Open
Abstract
Elizabethkingia anophelis has now emerged as an opportunistic human pathogen. However, its mechanisms of transmission remain unexplained. Comparative genomic (CG) analysis of E. anopheles endophthalmitis strain surprisingly found from an eye infection patient with twenty-five other E. anophelis genomes revealed its potential to participate in horizontal gene transfer. CG analysis revealed that the study isolate has an open pan genome and has undergone extensive gene rearrangements. We demonstrate that the strain is naturally competent, hitherto not reported in any members of Elizabethkingia. Presence of competence related genes, mobile genetic elements, Type IV, VI secretory systems and a unique virulence factor arylsulfatase suggests a different lineage of the strain. Deciphering the genome of E. anophelis having a reservoir of antibiotic resistance genes and virulence factors associated with diverse human infections may open up avenues to deal with the myriad of its human infections and devise strategies to combat the pathogen.
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Affiliation(s)
- Eswarappa Pradeep Bulagonda
- Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Puttaparthi, Andhra Pradesh, India.
| | - Bhavani Manivannan
- Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Puttaparthi, Andhra Pradesh, India
| | - Niranjana Mahalingam
- Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Puttaparthi, Andhra Pradesh, India.,Department of Microbiology, Sri Sathya Sai Institute of Higher Medical Sciences, Prasanthigram, Andhra Pradesh, India
| | - Manmath Lama
- Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Puttaparthi, Andhra Pradesh, India
| | - Pachi Pulusu Chanakya
- Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Puttaparthi, Andhra Pradesh, India
| | - Balaram Khamari
- Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Prasanthi Nilayam, Puttaparthi, Andhra Pradesh, India
| | - Sudhir Jadhao
- Bionivid technology Pvt Ltd, 4C-209, 4th cross, Kasturi Nagar, Bengaluru, India
| | - Madavan Vasudevan
- Bionivid technology Pvt Ltd, 4C-209, 4th cross, Kasturi Nagar, Bengaluru, India
| | - Valakunja Nagaraja
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India. .,Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India.
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38
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Niu X, Yu Y, Guo H, Yang Y, Wang G, Sun L, Gao Y, Yu Z, Wang H. Molecular modeling reveals the inhibition mechanism and binding mode of ursolic acid to TLR4-MD2. COMPUT THEOR CHEM 2018. [DOI: 10.1016/j.comptc.2017.11.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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39
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Insight into the novel inhibition mechanism of apigenin to Pneumolysin by molecular modeling. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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40
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Schwiering M, Husmann M, Hellmann N. P2X-Receptor Antagonists Inhibit the Interaction of S. aureus Hemolysin A with Membranes. Toxins (Basel) 2017; 9:toxins9100332. [PMID: 29048353 PMCID: PMC5666378 DOI: 10.3390/toxins9100332] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 10/08/2017] [Accepted: 10/15/2017] [Indexed: 11/21/2022] Open
Abstract
The pore forming hemolysin A, Hla, is a major virulence factor of Staphylococcus aureus. Apparently, 1–2 pore(s) per cell suffice(s) to cause cell death. Accumulated experimental evidence points towards a major role of ATP-gated purinergic receptors (P2XR) for hemolysis caused by Hla, complement and other pore forming proteins, presumably by increasing membrane permeability. Indeed, in experiments employing rabbit erythrocytes, inhibitory concentrations of frequently employed P2XR-antagonists were in a similar range as previously reported for erythrocytes of other species and other toxins. However, Hla-dependent hemolysis was not enhanced by extracellular ATP, and oxidized adenosinetriphosphate (oxATP) had only a minor inhibitory effect. Unexpectedly, P2XR-inhibitors also prevented Hla-induced lysis of pure lipid membranes, demonstrating that the inhibition did not even depend on the presence of P2XR. Fluorescence microscopy and gel-electrophoresis clearly revealed that P2XR-inhibitors interfere with binding and subsequent oligomerisation of Hla with membranes. Similar results were obtained employing HaCaT-cells. Furthermore, calorimetric data and hemolysis experiments with Hla pre-treated with pyridoxal phosphate-6-azophenyl-2′,4′-disulfonic acid (PPADS) showed that this compound directly binds to Hla. Our results call for a critical re-assessment of the appealing concept, which suggests that P2XR are general amplifiers of damage by pore-forming proteins.
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Affiliation(s)
- Markus Schwiering
- Institute for Molecular Biophysics, Jakob-Welder-Weg 26, University of Mainz, 55128 Mainz, Germany.
| | - Matthias Husmann
- Institute of Medical Microbiology and Hygiene, University Medical Center, Johannes Gutenberg-University Mainz, Hochhaus am Augustusplatz, 55131 Mainz, Germany.
| | - Nadja Hellmann
- Institute for Molecular Biophysics, Jakob-Welder-Weg 26, University of Mainz, 55128 Mainz, Germany.
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41
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Bilitewski U, Blodgett JAV, Duhme-Klair AK, Dallavalle S, Laschat S, Routledge A, Schobert R. Chemical and Biological Aspects of Nutritional Immunity-Perspectives for New Anti-Infectives that Target Iron Uptake Systems. Angew Chem Int Ed Engl 2017; 56:14360-14382. [PMID: 28439959 DOI: 10.1002/anie.201701586] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Indexed: 12/22/2022]
Abstract
Upon bacterial infection, one of the defense mechanisms of the host is the withdrawal of essential metal ions, in particular iron, which leads to "nutritional immunity". However, bacteria have evolved strategies to overcome iron starvation, for example, by stealing iron from the host or other bacteria through specific iron chelators with high binding affinity. Fortunately, these complex interactions between the host and pathogen that lead to metal homeostasis provide several opportunities for interception and, thus, allow the development of novel antibacterial compounds. This Review focuses on iron, discusses recent highlights, and gives some future perspectives which are relevant in the fight against antibiotic resistance.
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Affiliation(s)
- Ursula Bilitewski
- AG Compound Profiling and Screening, Helmholtz Zentrum für Infektionsforschung, Inhoffenstrasse 7, 38124, Braunschweig, Germany
| | - Joshua A V Blodgett
- Department of Biology, Washington University, St. Louis, MO, 63130-4899, USA
| | | | - Sabrina Dallavalle
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, I-20133, Milano, Italy
| | - Sabine Laschat
- Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 7, 0569, Stuttgart, Germany
| | - Anne Routledge
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
| | - Rainer Schobert
- Organische Chemie I, Universität Bayreuth, Universitätsstrasse 30, 95447, Bayreuth, Germany
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42
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Bilitewski U, Blodgett JAV, Duhme-Klair AK, Dallavalle S, Laschat S, Routledge A, Schobert R. Chemische und biologische Aspekte von “Nutritional Immunity” - Perspektiven für neue Antiinfektiva mit Fokus auf bakterielle Eisenaufnahmesysteme. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201701586] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Ursula Bilitewski
- AG Compound Profiling and Screening; Helmholtz-Zentrum für Infektionsforschung; Inhoffenstraße 7 38124 Braunschweig Deutschland
| | | | | | - Sabrina Dallavalle
- Department of Food, Environmental and Nutritional Sciences; Università degli Studi di Milano; I-20133 Milano Italien
| | - Sabine Laschat
- Institut für Organische Chemie; Universität Stuttgart; Pfaffenwaldring 55, 7 0569 Stuttgart Deutschland
| | - Anne Routledge
- Department of Chemistry; University of York, Heslington; York YO10 5DD Großbritannien
| | - Rainer Schobert
- Organische Chemie I; Universität Bayreuth; Universitätsstraße 30 95447 Bayreuth Deutschland
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43
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Han S, Xu J, Guo X, Huang M. Curcumin ameliorates severe influenza pneumonia via attenuating lung injury and regulating macrophage cytokines production. Clin Exp Pharmacol Physiol 2017; 45:84-93. [PMID: 28853207 DOI: 10.1111/1440-1681.12848] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Revised: 08/16/2017] [Accepted: 08/16/2017] [Indexed: 12/19/2022]
Abstract
Curcumin, an active phenolic agent extract from the Curcuma longa, exhibits excellent anti-cancer, anti-inflammation, and neuroprotective effects. We aimed to investigate the anti-influenza role of curcumin in vitro and in vivo. The effect of curcumin on replication of influenza A virus (IAV) was examined in human lung cancer cell line A549, as well as in a mouse model. Curcumin could inhibit IAV in vitro and alleviate the severity of the disease in the mouse after infection with IAV. The results also indicated that curcumin could trigger expression of Heme oxygenase-1 in vivo and attenuate IAV-induced injury to the lung tissue. Furthermore, curcumin could regulate immune response following IAV infection through inhibiting production of local inflammatory cytokines. In addition, curcumin was found to inhibit NF-κB signalling in macrophages, as well as the subsequent production of cytokines/chemokines responding to IAV infection, by enhancing IκBα and AMPK. Our current study supports the potential of curcumin as a promising treatment against IAV infection, whose effect may be mediated by regulating immune response to prevent injury to the lung tissue.
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Affiliation(s)
- Shuguang Han
- Department of Respiratory Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.,Department of Respiratory Medicine, Nanjing Medical University Affiliated Wuxi Second Hospital, Wuxi, China
| | - Jing Xu
- Department of Respiratory Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xiangjun Guo
- Department of Respiratory Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Mao Huang
- Department of Respiratory Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
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44
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Investigation of the inhibition effect and mechanism of myricetin to Suilysin by molecular modeling. Sci Rep 2017; 7:11748. [PMID: 28924148 PMCID: PMC5603505 DOI: 10.1038/s41598-017-12168-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 09/04/2017] [Indexed: 01/27/2023] Open
Abstract
In the present study, the inhibitory effect and mechanism of myricetin, a natural flavonoid compound, in relation to Suilysin (SLY) were investigated through molecular dynamics simulations, mutational analysis and fluorescence-quenching assays. Myricetin is a potential inhibitor that does not exhibit antimicrobial activity but has been shown to inhibit SLY cytotoxicity. Molecular dynamics simulations and mutational analysis revealed that myricetin binds directly to SLY in the gap between domains 2 and 3, an important region for oligomerization and pore formation. The results of principal component analysis (PCA) indicated that the binding of myricetin in this gap region restricts the conformational transition of SLY from a monomer to an oligomer, thereby counteracting the haemolytic activity of SLY. This mechanism was verified using a haemolysis assay. These results demonstrated that myricetin is a strong candidate as a novel therapeutic agent for the treatment of Streptococcus suis infections.
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45
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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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46
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Silva LN, Da Hora GCA, Soares TA, Bojer MS, Ingmer H, Macedo AJ, Trentin DS. Myricetin protects Galleria mellonella against Staphylococcus aureus infection and inhibits multiple virulence factors. Sci Rep 2017; 7:2823. [PMID: 28588273 PMCID: PMC5460262 DOI: 10.1038/s41598-017-02712-1] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 04/18/2017] [Indexed: 02/06/2023] Open
Abstract
Staphylococcus aureus is an opportunistic pathogen related to a variety of life-threatening infections but for which antimicrobial resistance is liming the treatment options. We report here that myricetin, but not its glycosylated form, can remarkably decrease the production of several S. aureus virulence factors, including adhesion, biofilm formation, hemolysis and staphyloxanthin production, without interfering with growth. Myricetin affects both surface proteins and secreted proteins which indicate that its action is unrelated to inhibition of the agr quorum sensing system. Analysis of virulence related gene expression and computational simulations of pivotal proteins involved in pathogenesis demonstrate that myricetin downregulates the saeR global regulator and interacts with sortase A and α-hemolysin. Furthermore, Myr confers a significant degree of protection against staphylococcal infection in the Galleria mellonella model. The present findings reveal the potential of Myr as an alternative multi-target antivirulence candidate to control S. aureus pathogenicity.
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Affiliation(s)
- L N Silva
- Centro de Biotecnologia do Estado do Rio Grande do Sul, Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre-RS, 91501-970, Brazil
- Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre-RS, 90610-000, Brazil
| | - G C A Da Hora
- Departmento de Química Fundamental, Universidade Federal de Pernambuco, Recife-PE, 50670-901, Brazil
| | - T A Soares
- Departmento de Química Fundamental, Universidade Federal de Pernambuco, Recife-PE, 50670-901, Brazil
- Department of Chemistry, Umeå University, 90187, Umeå, Sweden
| | - M S Bojer
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, 1870, Denmark
| | - H Ingmer
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, 1870, Denmark
| | - A J Macedo
- Centro de Biotecnologia do Estado do Rio Grande do Sul, Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre-RS, 91501-970, Brazil.
- Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre-RS, 90610-000, Brazil.
| | - D S Trentin
- Centro de Biotecnologia do Estado do Rio Grande do Sul, Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre-RS, 91501-970, Brazil
- Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre-RS, 90610-000, Brazil
- Departamento de Ciências Básicas da Saúde, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre-RS, 90050-170, Brazil
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47
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Zhou X, Zhang B, Cui Y, Chen S, Teng Z, Lu G, Wang J, Deng X. Curcumin Promotes the Clearance of Listeria monocytogenes both In Vitro and In Vivo by Reducing Listeriolysin O Oligomers. Front Immunol 2017; 8:574. [PMID: 28567044 PMCID: PMC5434164 DOI: 10.3389/fimmu.2017.00574] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 04/28/2017] [Indexed: 01/28/2023] Open
Abstract
The pore-forming toxin listeriolysin O (LLO), an essential virulence factor that is secreted by Listeria monocytogenes (L. monocytogenes), is responsible for bacterial breaching at the phagosomal membranes and subsequent release into the cytoplasm; it cannot be recognized by the host immune system. The vital role that LLO plays in bacterial pathogenicity and evading host immune clearance makes this virulence a promising target for addressing L. monocytogenes infection. In this study, we hypothesized that curcumin, a polyphenol derived from turmeric that could effectively inhibit LLO pore-forming activity, might be useful in the prevention or treatment of L. monocytogenes infection. Thus, the in vitro protective effects of curcumin against L. monocytogenes infection by targeting LLO were assessed via hemolytic activity assays, cytotoxicity tests, intracellular growth assays, and confocal microscopy. Our results revealed that treating infected macrophages with curcumin can lead to a decrease in LLO-mediated bacteria phagosomal escape and limit the intracellular growth of L. monocytogenes. Moreover, results from animal experiments show that this natural compound effectively increases protection against bacterial infection and helps the host to clear the invading pathogen completely from an animal model, establishing it as a potent antagonist of L. monocytogenes. The results from our molecular modeling and mutational analysis demonstrated that curcumin directly engages with domains 2 and 4 of LLO, thereby decreasing the hemolytic activity of LLO by influencing its oligomerization. Taken together, these results suggest that, as an antitoxin agent, curcumin can be further developed into a novel therapy against L. monocytogenes infections by targeting LLO.
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Affiliation(s)
- Xuan Zhou
- Center of Infection and Immunity, The First Hospital, Jilin University, Changchun, China.,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
| | - Yumei Cui
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Shuiye Chen
- 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
| | - Gejin Lu
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jianfeng Wang
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xuming Deng
- Center of Infection and Immunity, The First Hospital, Jilin University, Changchun, China.,Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
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48
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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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49
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Li G, Lu G, Qi Z, Li H, Wang L, Wang Y, Liu B, Niu X, Deng X, Wang J. Morin Attenuates Streptococcus suis Pathogenicity in Mice by Neutralizing Suilysin Activity. Front Microbiol 2017; 8:460. [PMID: 28373868 PMCID: PMC5357624 DOI: 10.3389/fmicb.2017.00460] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 03/06/2017] [Indexed: 12/24/2022] Open
Abstract
Streptococcus suis, a Gram-positive pathogen, is widely recognized as an important agent of swine infection, and it is also known to cause a variety of zoonoses, such as meningitis, polyarthritis and pneumonia. Suilysin (SLY), an extracellular pore-forming toxin that belongs to the cholesterol-dependent cytolysin family, is an essential virulence factor of S. suis capsular type 2 (SS2). Here, we found that morin hydrate (morin), a natural flavonoid that lacks anti-SS2 activity, inhibits the hemolytic activity of SLY, protects J774 cells from SS2-induced injury and protects mice from SS2 infection. Further, by molecular modeling and mutational analysis, we found that morin binds to the "stem" domain 2 in SLY and hinders its transformation from the monomer form to the oligomer form, which causes the loss of SLY activity. Our study demonstrates that morin hinders the cell lysis activity of SLY through a novel mechanism of interrupting the heptamer formation. These findings may lead to the development of promising therapeutic candidates for the treatment of SS2 infections.
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Affiliation(s)
- Gen Li
- The First Hospital and Institute of Infection and Immunity, Jilin UniversityChangchun, China; Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin UniversityChangchun, China
| | - Gejin Lu
- The First Hospital and Institute of Infection and Immunity, Jilin UniversityChangchun, China; Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin UniversityChangchun, China
| | - Zhimin Qi
- The First Hospital and Institute of Infection and Immunity, Jilin UniversityChangchun, China; Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin UniversityChangchun, China
| | - Hongen Li
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University Changchun, China
| | - Lin Wang
- The First Hospital and Institute of Infection and Immunity, Jilin UniversityChangchun, China; Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin UniversityChangchun, China
| | - Yanhui Wang
- Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University Changchun, China
| | - Bowen Liu
- The First Hospital and Institute of Infection and Immunity, Jilin UniversityChangchun, China; Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin UniversityChangchun, China
| | - Xiaodi Niu
- The First Hospital and Institute of Infection and Immunity, Jilin UniversityChangchun, China; Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin UniversityChangchun, China
| | - Xuming Deng
- The First Hospital and Institute of Infection and Immunity, Jilin UniversityChangchun, China; Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin UniversityChangchun, China
| | - Jianfeng Wang
- The First Hospital and Institute of Infection and Immunity, Jilin UniversityChangchun, China; Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin UniversityChangchun, China
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50
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Li H, Zhao X, Deng X, Wang J, Song M, Niu X, Peng L. Insights into structure and activity of natural compound inhibitors of pneumolysin. Sci Rep 2017; 7:42015. [PMID: 28165051 PMCID: PMC5292752 DOI: 10.1038/srep42015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 01/05/2017] [Indexed: 01/03/2023] Open
Abstract
Pneumolysin is the one of the major virulence factor of the bacterium Streptococcus pneumoniae. In previous report, it is shown that β-sitosterol, a natural compound without antimicrobial activity, is a potent antagonist of pneumolysin. Here, two new pneumolysin natural compound inhibitors, with differential activity, were discovered via haemolysis assay. To explore the key factor of the conformation for the inhibition activity, the interactions between five natural compound inhibitors with differential activity and pneumolysin were reported using molecular modelling, the potential of mean force profiles. Interestingly, it is found that incorporation of the single bond (C22-C23-C24-C25) to replace the double bond (hydrocarbon sidechain) improved the anti-haemolytic activity. In view of the molecular modelling, binding of the five inhibitors to the conserved loop region (Val372, Leu460, and Tyr461) of the cholesterol binding sites led to stable complex systems, which was consistent with the result of β-sitosterol. Owing to the single bond (C22-C23-C24-C25), campesterol and brassicasterol could form strong interactions with Val372 and show higher anti-haemolytic activity, which indicated that the single bond (C22-C23-C24-C25) in inhibitors was required for the anti-haemolytic activity. Overall, the current molecular modelling work provides a starting point for the development of rational design and higher activity pneumolysin inhibitors.
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Affiliation(s)
- Hongen Li
- Department of Respiratory Medicine, The First Hospital of Jilin University, Key Laboratory of Zoonosis, Ministry of Education, Department of Food Quality and Safety, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xiaoran Zhao
- Department of Respiratory Medicine, The First Hospital of Jilin University, Key Laboratory of Zoonosis, Ministry of Education, Department of Food Quality and Safety, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xuming Deng
- Department of Respiratory Medicine, The First Hospital of Jilin University, Key Laboratory of Zoonosis, Ministry of Education, Department of Food Quality and Safety, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jianfeng Wang
- Department of Respiratory Medicine, The First Hospital of Jilin University, Key Laboratory of Zoonosis, Ministry of Education, Department of Food Quality and Safety, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Meng Song
- Department of Respiratory Medicine, The First Hospital of Jilin University, Key Laboratory of Zoonosis, Ministry of Education, Department of Food Quality and Safety, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xiaodi Niu
- Department of Respiratory Medicine, The First Hospital of Jilin University, Key Laboratory of Zoonosis, Ministry of Education, Department of Food Quality and Safety, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Liping Peng
- Department of Respiratory Medicine, The First Hospital of Jilin University, Key Laboratory of Zoonosis, Ministry of Education, Department of Food Quality and Safety, College of Veterinary Medicine, Jilin University, Changchun, China
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