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Zhang P, Ma Y, Wang Y, Dong E, Ma S. Design, Synthesis, and Biological Evaluation of 2-Phenoxyalkylhydrazide Benzoxazole Derivatives as Quorum Sensing Inhibitors with Strong Antibiofilm Effect. J Med Chem 2024; 67:5721-5743. [PMID: 38564271 DOI: 10.1021/acs.jmedchem.3c02379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
With the increasing problem of bacterial resistance to traditional antibiotics, there is an urgent need for new antibacterial agents with novel mechanisms to treat infections caused by drug-resistant bacteria. In this paper, we designed and synthesized 2-phenoxyalkylhydrazide benzoxazole derivatives and evaluated their quorum sensing inhibition activity. Among them, 26c at a concentration of 102.4 μg/mL not only inhibited the production of pyocyanin and rhamnolipid by 45.6% and 38.3%, respectively, but also suppressed 76.6% of biofilm production at 32 μg/mL. In addition, 26c did not affect bacterial growth, but in a mouse model infected with P. aeruginosa PAO1, it could help ciprofloxacin effectively eliminate the living bacteria. In the targeting experiment, 26c could inhibit the fluorescence intensity of PAO1-lasB-gfp and PAO1-pqsA-gfp in a concentration-dependent manner, indicating that the compound acts on the quorum sensing system. Overall, 26c is worthy of further investigation as a quorum sensing inhibitor with strong antibiofilm effect.
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Affiliation(s)
- Panpan Zhang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan 250012, China
| | - Yangchun Ma
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan 250012, China
| | - Yingmei Wang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan 250012, China
| | - Enhui Dong
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan 250012, China
| | - Shutao Ma
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan 250012, China
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2
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Deery J, Carmody M, Flavin R, Tomanek M, O'Keeffe M, McGlacken GP, Reen FJ. Comparative genomics reveals distinct diversification patterns among LysR-type transcriptional regulators in the ESKAPE pathogen Pseudomonas aeruginosa. Microb Genom 2024; 10:001205. [PMID: 38421269 PMCID: PMC10926688 DOI: 10.1099/mgen.0.001205] [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: 10/05/2023] [Accepted: 02/06/2024] [Indexed: 03/02/2024] Open
Abstract
Pseudomonas aeruginosa, a harmful nosocomial pathogen associated with cystic fibrosis and burn wounds, encodes for a large number of LysR-type transcriptional regulator proteins. To understand how and why LTTR proteins evolved with such frequency and to establish whether any relationships exist within the distribution we set out to identify the patterns underpinning LTTR distribution in P. aeruginosa and to uncover cluster-based relationships within the pangenome. Comparative genomic studies revealed that in the JGI IMG database alone ~86 000 LTTRs are present across the sequenced genomes (n=699). They are widely distributed across the species, with core LTTRs present in >93 % of the genomes and accessory LTTRs present in <7 %. Analysis showed that subsets of core LTTRs can be classified as either variable (typically specific to P. aeruginosa) or conserved (and found to be distributed in other Pseudomonas species). Extending the analysis to the more extensive Pseudomonas database, PA14 rooted analysis confirmed the diversification patterns and revealed PqsR, the receptor for the Pseudomonas quinolone signal (PQS) and 2-heptyl-4-quinolone (HHQ) quorum-sensing signals, to be amongst the most variable in the dataset. Successful complementation of the PAO1 pqsR - mutant using representative variant pqsR sequences suggests a degree of structural promiscuity within the most variable of LTTRs, several of which play a prominent role in signalling and communication. These findings provide a new insight into the diversification of LTTR proteins within the P. aeruginosa species and suggests a functional significance to the cluster, conservation and distribution patterns identified.
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Affiliation(s)
- Jamie Deery
- School of Microbiology, University College Cork, Cork, Ireland
| | - Muireann Carmody
- School of Microbiology, University College Cork, Cork, Ireland
- School of Chemistry, University College Cork, Cork, Ireland
| | - Rhiannon Flavin
- School of Microbiology, University College Cork, Cork, Ireland
| | - Malwina Tomanek
- School of Microbiology, University College Cork, Cork, Ireland
| | - Maria O'Keeffe
- School of Microbiology, University College Cork, Cork, Ireland
| | - Gerard P. McGlacken
- School of Chemistry, University College Cork, Cork, Ireland
- Synthesis and Solid State Pharmaceutical Centre, University College Cork, Cork, Ireland
| | - F. Jerry Reen
- School of Microbiology, University College Cork, Cork, Ireland
- Synthesis and Solid State Pharmaceutical Centre, University College Cork, Cork, Ireland
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3
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Mollova-Sapundzhieva Y, Angelov P, Georgiev D, Yanev P. Synthetic approach to 2-alkyl-4-quinolones and 2-alkyl-4-quinolone-3-carboxamides based on common β-keto amide precursors. Beilstein J Org Chem 2023; 19:1804-1810. [PMID: 38033452 PMCID: PMC10682542 DOI: 10.3762/bjoc.19.132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 11/16/2023] [Indexed: 12/02/2023] Open
Abstract
β-Keto amides were used as convenient precursors to both 2-alkyl-4-quinolones and 2-alkyl-4-quinolone-3-carboxamides. The utility of this approach is demonstrated with the synthesis of fourteen novel and four known quinolone derivatives, including natural products of microbial origin such as HHQ and its C5-congener. Two compounds with high activity against S. aureus have been identified among the newly obtained quinolones, with MICs ≤ 3.12 and ≤ 6.25 µg/mL, respectively.
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Affiliation(s)
- Yordanka Mollova-Sapundzhieva
- Department of Organic Chemistry, University of Plovdiv Paisii Hilendarski, 24 Tsar Asen Str., 4000 Plovdiv, Bulgaria
| | - Plamen Angelov
- Department of Organic Chemistry, University of Plovdiv Paisii Hilendarski, 24 Tsar Asen Str., 4000 Plovdiv, Bulgaria
| | - Danail Georgiev
- Department of Biochemistry and Microbiology, University of Plovdiv Paisii Hilendarski, 24 Tsar Asen Str., 4000 Plovdiv, Bulgaria
| | - Pavel Yanev
- Department of Organic Chemistry, University of Plovdiv Paisii Hilendarski, 24 Tsar Asen Str., 4000 Plovdiv, Bulgaria
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Al Mamari HH, Borel J, Hickey A, Courtney E, Merz J, Zhang X, Friedrich A, Marder TB, McGlacken GP. Regioselective Iridium-Catalyzed C8-H Borylation of 4-Quinolones via Transient O-Borylated Quinolines. Chemistry 2023; 29:e202301734. [PMID: 37280155 DOI: 10.1002/chem.202301734] [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: 06/01/2023] [Revised: 06/04/2023] [Accepted: 06/05/2023] [Indexed: 06/08/2023]
Abstract
The quinolone-quinoline tautomerization is harnessed to effect the regioselective C8-borylation of biologically important 4-quinolones by using [Ir(OMe)(cod)]2 as the catalyst precursor, the silica-supported monodentate phosphine Si-SMAP as the ligand, and B2 pin2 as the boron source. Initially, O-borylation of the quinoline tautomer takes place. Critically, the newly formed 4-(pinBO)-quinolines then undergo N-directed selective Ir-catalyzed borylation at C8. Hydrolysis of the OBpin moiety on workup returns the system to the quinolone tautomer. The C8-borylated quinolines were converted to their corresponding potassium trifluoroborate (BF3 K) salts and to their C8-chlorinated quinolone derivatives. The two-step C-H borylation-chlorination reaction sequence resulted in various C8-Cl quinolones in good yields. Conversion to C8-OH-, C8-NH2 -, and C8-Ar-substituted quinolones was also feasible by using this methodology.
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Affiliation(s)
- Hamad H Al Mamari
- Department of Chemistry, College of Science, Sultan Qaboos University, PO Box 36, Al Khoudh 123, Muscat, Sultanate of Oman
- Institut für Anorganische Chemie and, Institute for Sustainable Chemistry & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Julie Borel
- Institut für Anorganische Chemie and, Institute for Sustainable Chemistry & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Aobha Hickey
- School of Chemistry & Analytical and, Biological Chemistry Research Facility, University College Cork, T12 YN60, Ireland
| | - Eimear Courtney
- School of Chemistry & Analytical and, Biological Chemistry Research Facility, University College Cork, T12 YN60, Ireland
| | - Julia Merz
- Institut für Anorganische Chemie and, Institute for Sustainable Chemistry & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Xiaolei Zhang
- Institut für Anorganische Chemie and, Institute for Sustainable Chemistry & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Alexandra Friedrich
- Institut für Anorganische Chemie and, Institute for Sustainable Chemistry & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Todd B Marder
- Institut für Anorganische Chemie and, Institute for Sustainable Chemistry & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Gerard P McGlacken
- School of Chemistry & Analytical and, Biological Chemistry Research Facility, University College Cork, T12 YN60, Ireland
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Escobar-Salom M, Barceló IM, Jordana-Lluch E, Torrens G, Oliver A, Juan C. Bacterial virulence regulation through soluble peptidoglycan fragments sensing and response: knowledge gaps and therapeutic potential. FEMS Microbiol Rev 2023; 47:fuad010. [PMID: 36893807 PMCID: PMC10039701 DOI: 10.1093/femsre/fuad010] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 02/10/2023] [Accepted: 03/07/2023] [Indexed: 03/11/2023] Open
Abstract
Given the growing clinical-epidemiological threat posed by the phenomenon of antibiotic resistance, new therapeutic options are urgently needed, especially against top nosocomial pathogens such as those within the ESKAPE group. In this scenario, research is pushed to explore therapeutic alternatives and, among these, those oriented toward reducing bacterial pathogenic power could pose encouraging options. However, the first step in developing these antivirulence weapons is to find weak points in the bacterial biology to be attacked with the goal of dampening pathogenesis. In this regard, during the last decades some studies have directly/indirectly suggested that certain soluble peptidoglycan-derived fragments display virulence-regulatory capacities, likely through similar mechanisms to those followed to regulate the production of several β-lactamases: binding to specific transcriptional regulators and/or sensing/activation of two-component systems. These data suggest the existence of intra- and also intercellular peptidoglycan-derived signaling capable of impacting bacterial behavior, and hence likely exploitable from the therapeutic perspective. Using the well-known phenomenon of peptidoglycan metabolism-linked β-lactamase regulation as a starting point, we gather and integrate the studies connecting soluble peptidoglycan sensing with fitness/virulence regulation in Gram-negatives, dissecting the gaps in current knowledge that need filling to enable potential therapeutic strategy development, a topic which is also finally discussed.
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Affiliation(s)
- María Escobar-Salom
- Research Unit and Microbiology Department, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Crtra. Valldemossa 79, 07010 Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC). Av. Monforte de Lemos 3-5, 28029, Madrid, Spain
| | - Isabel María Barceló
- Research Unit and Microbiology Department, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Crtra. Valldemossa 79, 07010 Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC). Av. Monforte de Lemos 3-5, 28029, Madrid, Spain
| | - Elena Jordana-Lluch
- Research Unit and Microbiology Department, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Crtra. Valldemossa 79, 07010 Palma, Spain
| | - Gabriel Torrens
- Research Unit and Microbiology Department, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Crtra. Valldemossa 79, 07010 Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC). Av. Monforte de Lemos 3-5, 28029, Madrid, Spain
- Department of Molecular Biology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Umeå University. Försörjningsvägen 2A, SE-901 87 Umeå, Sweden
| | - Antonio Oliver
- Research Unit and Microbiology Department, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Crtra. Valldemossa 79, 07010 Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC). Av. Monforte de Lemos 3-5, 28029, Madrid, Spain
| | - Carlos Juan
- Research Unit and Microbiology Department, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Crtra. Valldemossa 79, 07010 Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC). Av. Monforte de Lemos 3-5, 28029, Madrid, Spain
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6
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Qi YK, Tang X, Wei NN, Pang CJ, Du SS, Wang KW. Discovery, synthesis, and optimization of teixobactin, a novel antibiotic without detectable bacterial resistance. J Pept Sci 2022; 28:e3428. [PMID: 35610021 DOI: 10.1002/psc.3428] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2021] [Revised: 05/07/2022] [Accepted: 05/10/2022] [Indexed: 11/09/2022]
Abstract
Discovering new antibiotics with novel chemical scaffolds and antibacterial mechanisms presents a challenge for medicinal scientists worldwide as the ever-increasing bacterial resistance poses a serious threat to human health. A new cyclic peptide-based antibiotic termed teixobactin was discovered from a screen of uncultured soil bacteria through iChip technology in 2015. Teixobactin exhibits excellent antibacterial activity against all the tested gram-positive pathogens and Mycobacterium tuberculosis, including drug-resistant strains. Given that teixobactin targets the highly conserved lipid II and lipid III, which induces the simultaneous inhibition of both peptidoglycan and teichoic acid synthesis, the emergence of resistance is considered to be rather difficult. The novel structure, potent antibacterial activity, and highly conservative targets make teixobactin a promising lead compound for further antibiotic development. This review provides a comprehensive treatise on the advances of teixobactin in the areas of discovery processes, antibacterial activity, mechanisms of action, chemical synthesis, and structural optimizations. The synthetic methods for the key building block l-allo-End, natural teixobactin, representative teixobactin analogues, as well as the structure-activity relationship studies will be highlighted and discussed in details. Finally, some insights into new trends for the generation of novel teixobactin analogues and tips for future work and directions will be commented.
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Affiliation(s)
- Yun-Kun Qi
- Department of Medicinal Chemistry, School of Pharmacy, Qingdao University, Qingdao, China.,Institute of Innovative Drugs, Qingdao University, Qingdao, China.,State Key Laboratory Base for Eco-Chemical Engineering in College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, China
| | - Xiaowen Tang
- Department of Medicinal Chemistry, School of Pharmacy, Qingdao University, Qingdao, China
| | - Ning-Ning Wei
- Institute of Innovative Drugs, Qingdao University, Qingdao, China
| | - Cheng-Jian Pang
- The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Shan-Shan Du
- State Key Laboratory Base for Eco-Chemical Engineering in College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, China
| | - Ke Wei Wang
- Department of Medicinal Chemistry, School of Pharmacy, Qingdao University, Qingdao, China.,Institute of Innovative Drugs, Qingdao University, Qingdao, China
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7
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Pandey M, Wasnik K, Gupta S, Singh M, Patra S, Gupta P, Pareek D, Maity S, Tilak R, Paik P. Targeted specific inhibition of bacterial and Candida species by mesoporous Ag/Sn-SnO 2 composite nanoparticles: in silico and in vitro investigation. RSC Adv 2021; 12:1105-1120. [PMID: 35425144 PMCID: PMC8978812 DOI: 10.1039/d1ra07594b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 12/15/2021] [Indexed: 02/06/2023] Open
Abstract
Invasive bacterial and fungal infections have notably increased the burden on the health care system and especially in immune compromised patients. These invasive bacterial and fungal species mimic and interact with the host extracellular matrix and increase the adhesion and internalization into the host system. Further, increased resistance of traditional antibiotics/antifungal drugs led to the demand for other therapeutics and preventive measures. Presently, metallic nanoparticles have wide applications in health care sectors. The present study has been designed to evaluate the advantage of Ag/Sn-SnO2 composite nanoparticles over the single oxide/metallic nanoparticles. By using in silico molecular docking approaches, herein we have evaluated the effects of Ag/Sn-SnO2 nanoparticles on adhesion and invasion responsible molecular targets such as LpfD (E. coli), Als3 (C. albicans) and on virulence/resistance causing PqsR (P. aeruginosa), RstA (Bmfr) (A. baumannii), FoxA (K. pneumonia), Hsp90 and Cyp51 (C. albicans). These Ag/Sn-SnO2 nanoparticles exhibited higher antimicrobial activities, especially against the C. albicans, which are the highest ever reported results. Further, Ag/Sn-SnO2 NPs exhibited interaction with the heme proionate residues such as Lys143, His468, Tyr132, Arg381, Phe105, Gly465, Gly464, Ile471 and Ile304 by forming hydrogen bonds with the Arg 381 residue of lanosterol 1 4α-demethylase and increased the inhibition of the Candida strains. Additionally, the Ag/Sn-SnO2 nanoparticles exhibited extraordinary inhibitory properties by targeting different proteins of bacteria and Candida species followed by several molecular pathways which indicated that it can be used to eliminate the resistance to traditional antibiotics.
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Affiliation(s)
- Monica Pandey
- School of Engineering Sciences and Technology, University of Hyderabad Telangana 500046 India
| | - Kirti Wasnik
- School of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU) Varanasi Uttar Pradesh 221005 India
| | - Shubhra Gupta
- School of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU) Varanasi Uttar Pradesh 221005 India
| | - Monika Singh
- School of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU) Varanasi Uttar Pradesh 221005 India
| | - Sukanya Patra
- School of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU) Varanasi Uttar Pradesh 221005 India
| | - Premshankar Gupta
- School of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU) Varanasi Uttar Pradesh 221005 India
| | - Divya Pareek
- School of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU) Varanasi Uttar Pradesh 221005 India
| | - Somedutta Maity
- School of Engineering Sciences and Technology, University of Hyderabad Telangana 500046 India
| | - Ragini Tilak
- Institute of Medical Sciences, Banaras Hindu University (BHU) Varanasi Uttar Pradesh 221005 India
| | - Pradip Paik
- School of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU) Varanasi Uttar Pradesh 221005 India
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8
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Duplantier M, Lohou E, Sonnet P. Quorum Sensing Inhibitors to Quench P. aeruginosa Pathogenicity. Pharmaceuticals (Basel) 2021; 14:1262. [PMID: 34959667 PMCID: PMC8707152 DOI: 10.3390/ph14121262] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/01/2021] [Accepted: 12/02/2021] [Indexed: 12/22/2022] Open
Abstract
The emergence and the dissemination of multidrug-resistant bacteria constitute a major public health issue. Among incriminated Gram-negative bacteria, Pseudomonas aeruginosa has been designated by the WHO as a critical priority threat. During the infection process, this pathogen secretes various virulence factors in order to adhere and colonize host tissues. Furthermore, P. aeruginosa has the capacity to establish biofilms that reinforce its virulence and intrinsic drug resistance. The regulation of biofilm and virulence factor production of this micro-organism is controlled by a specific bacterial communication system named Quorum Sensing (QS). The development of anti-virulence agents targeting QS that could attenuate P. aeruginosa pathogenicity without affecting its growth seems to be a promising new therapeutic strategy. This could prevent the selective pressure put on bacteria by the conventional antibiotics that cause their death and promote resistant strain survival. This review describes the QS-controlled pathogenicity of P. aeruginosa and its different specific QS molecular pathways, as well as the recent advances in the development of innovative QS-quenching anti-virulence agents to fight anti-bioresistance.
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Affiliation(s)
| | | | - Pascal Sonnet
- AGIR, UR4294, UFR of Pharmacy, Jules Verne University of Picardie, 80037 Amiens, France; (M.D.); (E.L.)
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9
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Pandey M, Singh M, Wasnik K, Gupta S, Patra S, Gupta PS, Pareek D, Chaitanya NSN, Maity S, Reddy ABM, Tilak R, Paik P. Targeted and Enhanced Antimicrobial Inhibition of Mesoporous ZnO-Ag 2O/Ag, ZnO-CuO, and ZnO-SnO 2 Composite Nanoparticles. ACS OMEGA 2021; 6:31615-31631. [PMID: 34869986 PMCID: PMC8637601 DOI: 10.1021/acsomega.1c04139] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 11/08/2021] [Indexed: 05/04/2023]
Abstract
In this work, mesoporous (pore size below 4 nm) composite nanoparticles of ZnO-Ag2O/Ag, ZnO-CuO, and ZnO-SnO2 of size d ≤ 10 nm (dia.) have been synthesized through the in situ solvochemical reduction method using NaBH4. These composite nanoparticles exhibited excellent killing efficacy against Gram-positive/negative bacterial and fungal strains even at a very low dose of 0.010 μg/mL. Additionally, by applying the in silico docking approach, the nanoparticles and microorganism-specific targeted proteins and their interactions have been identified to explain the best anti-bacterial/anti-fungal activities of these composites. For this purpose, the virulence and resistance causing target proteins such as PqsR, RstA, FosA, and Hsp90 of Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae, and Candida albicans have been identified to find out the best inhibitory action mechanisms involved. From the in vitro study, it is revealed that all the composite nanoparticle types used here can act as potent antimicrobial components. All the composite nanoparticles have exhibited excellent inhibition against the microorganisms compared to their constituent single metal or metal oxide nanoparticles. Among the nanoparticle types, the ZnO-Ag2O/Ag composite nanoparticles exhibited the best inhibition activity compared to the other reported nanoparticles. The microorganisms which are associated with severe infections lead to the multidrug resistance and have become a huge concern in the healthcare sector. Conventional organic antibiotics are less stable at a higher temperature. Therefore, based on the current demands, this work has been focused on designing inorganic antibiotics which possess stability even under harsh conditions. In this direction, our developed composite nanoparticles were explored for potential uses in the healthcare technology, and they may solve many problems in global emergency and epidemics caused by the microorganisms.
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Affiliation(s)
- Monica Pandey
- School
of Engineering Sciences and Technology, University of Hyderabad, Hyderabad, Telangana 500046, India
| | - Monika Singh
- School
of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Kirti Wasnik
- School
of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Shubhra Gupta
- School
of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Sukanya Patra
- School
of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Prem Shankar Gupta
- School
of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Divya Pareek
- School
of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Nyshadham Sai Naga Chaitanya
- Department
of Animal Science, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana 500046, India
| | - Somedutta Maity
- School
of Engineering Sciences and Technology, University of Hyderabad, Hyderabad, Telangana 500046, India
| | - Aramati B. M. Reddy
- Department
of Animal Science, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana 500046, India
| | - Ragini Tilak
- Institute
of Medical Sciences, Banaras Hindu University
(BHU), Varanasi, Uttar Pradesh 221005, India
| | - Pradip Paik
- School
of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University (BHU), Varanasi, Uttar Pradesh 221005, India
- ,
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10
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Nazik H, Sass G, Williams P, Déziel E, Stevens DA. Molecular Modifications of the Pseudomonas Quinolone Signal in the Intermicrobial Competition with Aspergillus. J Fungi (Basel) 2021; 7:jof7050343. [PMID: 33925067 PMCID: PMC8146305 DOI: 10.3390/jof7050343] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 02/03/2023] Open
Abstract
The Pseudomonas quinolone signal (PQS) is an important quorum-sensing molecule for Pseudomonas aeruginosa that regulates virulence factors, chelates iron, and is an important factor in interactions with eukaryotes, including fungi and mammalian hosts. It was previously shown to inhibit or boost Aspergillus, depending on the milieu iron concentration. We studied several molecular modifications of the PQS molecule, and their effects on Aspergillus biofilm metabolism and growth in vitro, and the effects of iron supplementation. We found that most molecules inhibited Aspergillus at concentrations similar to that of PQS, but with relatively flat dose-responses, and all were less potent than PQS. The inhibition was reversible by iron, suggesting interference with fungal iron metabolism. Stimulation of Aspergillus was not noted. We conclude that the critical Aspergillus-inhibiting moeities of the PQS molecule were partially, but not completely, interfered with by molecular modifications at several sites on the PQS molecule. The mechanism, as with PQS, appears to relate to fungal iron metabolism.
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Affiliation(s)
- Hasan Nazik
- Infectious Diseases Research Laboratory, California Institute for Medical Research, San Jose, CA 95128, USA; (H.N.); (G.S.)
| | - Gabriele Sass
- Infectious Diseases Research Laboratory, California Institute for Medical Research, San Jose, CA 95128, USA; (H.N.); (G.S.)
| | - Paul Williams
- Biodiscovery Institute and School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, UK;
| | - Eric Déziel
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, QC H7V 1B7, Canada;
| | - David A. Stevens
- Infectious Diseases Research Laboratory, California Institute for Medical Research, San Jose, CA 95128, USA; (H.N.); (G.S.)
- Division of Infectious Diseases and Geographic Medicine, Stanford University Medical School, Stanford, CA 94305, USA
- Correspondence: ; Tel.: +1-408-998-4554
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11
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Regulatory mechanisms of sub-inhibitory levels antibiotics agent in bacterial virulence. Appl Microbiol Biotechnol 2021; 105:3495-3505. [PMID: 33893838 DOI: 10.1007/s00253-021-11291-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 04/01/2021] [Accepted: 04/11/2021] [Indexed: 01/13/2023]
Abstract
Antibiotics play a key role in the prevention and treatment of bacterial diseases for human and animals. The widespread use of antibiotics results in bacterial exposure to the concentrations that are lower than the MIC (that is, sub-inhibitory concentration (sub-MIC)) in the environment, humans, and livestock, which can lead to antibiotic resistance. In this review, we focus on the impact of sub-MIC antibiotics in bacterial virulence. This paper summarized the known relationships between sub-MIC antibiotics in the environment and bacterial virulence. Together, considering the impact of sub-MIC antibiotics and their alternative products in the virulence of bacteria, it is helpful to the rational use of antibiotics and the development of antibiotic alternative products to provide new insights.Key points• Sub-MIC level antibiotics exist in the environment, humans, and livestock.• The review includes mechanisms of sub-MIC antibiotics in bacterial virulence.• New antibacterial strategies and agents are being a new way to weaken virulence. Graphical Abstract.
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12
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Thioether-linked dihydropyrrol-2-one analogues as PqsR antagonists against antibiotic resistant Pseudomonas aeruginosa. Bioorg Med Chem 2021; 31:115967. [PMID: 33434766 DOI: 10.1016/j.bmc.2020.115967] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 12/15/2020] [Accepted: 12/18/2020] [Indexed: 02/07/2023]
Abstract
The Pseudomonas quinolone system (pqs) is one of the key quorum sensing systems in antibiotic-resistant P. aeruginosa and is responsible for the production of virulence factors and biofilm formation. Thus, synthetic small molecules that can target the PqsR (MvfR) receptor can be utilized as quorum sensing inhibitors to treat P. aeruginosa infections. In this study, we report the synthesis of novel thioether-linked dihydropyrrol-2-one (DHP) analogues as PqsR antagonists. Compound 7g containing a 2-mercaptopyridyl linkage effectively inhibited the pqs system with an IC50 of 32 µM in P. aeruginosa PAO1. Additionally, these inhibitors significantly reduced bacterial aggregation and biofilm formation without affecting planktonic growth. The molecular docking study suggest that these inhibitors bind with the ligand binding domain of the MvfR as a competitive antagonist.
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13
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Ramos AF, Woods DF, Shanahan R, Cano R, McGlacken GP, Serra C, O'Gara F, Reen FJ. A structure-function analysis of interspecies antagonism by the 2-heptyl-4-alkyl-quinolone signal molecule from Pseudomonas aeruginosa. MICROBIOLOGY-SGM 2020; 166:169-179. [PMID: 31860435 DOI: 10.1099/mic.0.000876] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In recent years, the alkyl-quinolone molecular framework has already provided a rich source of bioactivity for the development of novel anti-infective compounds. Based on the quorum-sensing signalling molecules 4-hydroxy-2-heptylquinoline (HHQ) and 3,4-dihydroxy-2-heptylquinoline (PQS) from the nosocomial pathogen Pseudomonas aeruginosa, modifications have been developed with markedly enhanced anti-biofilm bioactivity towards important fungal and bacterial pathogens, including Candida albicans and Aspergillus fumigatus. Here we show that antibacterial activity of HHQ against Vibrionaceae is species-specific and it requires an exquisite level of structural fidelity within the alkyl-quinolone molecular framework. Antibacterial activity was demonstrated against the serious human pathogens Vibrio vulnificus and Vibrio cholerae as well as a panel of bioluminescent squid symbiont Allivibrio fischeri isolates. In contrast, Vibrio parahaemolyticus growth and biofilm formation was unaffected in the presence of HHQ and all the structural variants tested. In general, modification to almost all of the molecule except the alkyl-chain end, led to loss of activity. This suggests that the bacteriostatic activity of HHQ requires the concerted action of the entire framework components. The only exception to this pattern was deuteration of HHQ at the C3 position. HHQ modified with a terminal alkene at the quinolone alkyl chain retained bacteriostatic activity and was also found to activate PqsR signalling comparable to the native agonist. The data from this integrated analysis provides novel insights into the structural flexibility underpinning the signalling activity of the complex alkyl-quinolone molecular communication system.
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Affiliation(s)
- Ana F Ramos
- CIIMAR, -Centro Interdisciplinar de Investigação Marinha e Ambiental University of Porto, Porto Matosinhos, Portugal.,Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | - David F Woods
- BIOMERIT Research Centre, School of Microbiology, University College Cork, Cork, Ireland
| | - Rachel Shanahan
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Rafael Cano
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Gerard P McGlacken
- SSPC, Synthesis and Solid State Pharmaceutical Centre, Ireland.,School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Claudia Serra
- CIIMAR, -Centro Interdisciplinar de Investigação Marinha e Ambiental University of Porto, Porto Matosinhos, Portugal
| | - Fergal O'Gara
- BIOMERIT Research Centre, School of Microbiology, University College Cork, Cork, Ireland.,Telethon Kids Institute, Perth Children's Hospital, PerthWA 6009, Australia.,SSPC, Synthesis and Solid State Pharmaceutical Centre, Ireland.,School of Pharmacy and Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, PerthWA, Australia
| | - F Jerry Reen
- School of Microbiology, University College Cork, Cork, Ireland
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14
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Cajaninstilbene acid analogues as novel quorum sensing and biofilm inhibitors of Pseudomonas aeruginosa. Microb Pathog 2020; 148:104414. [DOI: 10.1016/j.micpath.2020.104414] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 05/20/2020] [Accepted: 07/21/2020] [Indexed: 01/09/2023]
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15
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Li J, Clark BR. Synthesis of Natural and Unnatural Quinolones Inhibiting the Growth and Motility of Bacteria. JOURNAL OF NATURAL PRODUCTS 2020; 83:3181-3190. [PMID: 33047958 DOI: 10.1021/acs.jnatprod.0c00865] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Synthesis of a recently discovered S-methylated quinolone natural product (1) was carried out, in addition to the production of a range of 2-substituted 4-quinolone derivatives (2-11). Two approaches were used: (i) the base-catalyzed cyclization of N-(ketoaryl)amides; (ii) attachment of the substituent to the quinolone core via a Suzuki-Miyaura cross-coupling. Also produced were a small suite of related 2(1H)-quinolones (12-19). The synthesized compounds were assessed for their antimicrobial properties. The alkene-substituted 4-quinolone 8 significantly inhibited the growth of a Pseudomonas aeruginosa strain, and both 4-quinolones and 2(1H)-quinolones were capable of inhibiting the swarming behavior of Bacillus subtilis.
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Affiliation(s)
- Jianye Li
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300092, People's Republic of China
| | - Benjamin R Clark
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300092, People's Republic of China
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16
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Buch PJ, Chai Y, Goluch ED. Bacterial chatter in chronic wound infections. Wound Repair Regen 2020; 29:106-116. [PMID: 33047459 DOI: 10.1111/wrr.12867] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 08/07/2020] [Accepted: 10/06/2020] [Indexed: 11/29/2022]
Abstract
One of the hallmark characteristics of chronic diabetic wounds is the presence of biofilm-forming bacteria. Bacteria encapsulated in a biofilm may coexist as a polymicrobial community and communicate with each other through a phenomenon termed quorum sensing (QS). Here, we describe the QS circuits of bacterial species commonly found in chronic diabetic wounds. QS relies on diffusion of signaling molecules and the local concentration changes of these molecules that bacteria experience in wounds. These biochemical signaling pathways play a role not only in biofilm formation and virulence but also in wound healing. They are, therefore, key to understanding the distinctive nature of these infections. While several in vivo and in vitro models exist to study QS in wounds, there has been limited progress in understanding the interplay between QS molecules and host factors that contribute to wound healing. Lastly, we examine the potential of targeting QS for both diagnosis and therapeutic intervention purposes.
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Affiliation(s)
- Pranali J Buch
- Department of Chemical Engineering, Northeastern University, Boston, Massachusetts, USA
| | - Yunrong Chai
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Edgar D Goluch
- Department of Chemical Engineering, Northeastern University, Boston, Massachusetts, USA.,Department of Biology, Northeastern University, Boston, Massachusetts, USA
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17
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Shaw E, Wuest WM. Virulence attenuating combination therapy: a potential multi-target synergy approach to treat Pseudomonas aeruginosa infections in cystic fibrosis patients. RSC Med Chem 2020; 11:358-369. [PMID: 33479641 PMCID: PMC7580779 DOI: 10.1039/c9md00566h] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 02/06/2020] [Indexed: 12/15/2022] Open
Abstract
The World Health Organization considers the discovery of new treatments for P. aeruginosa a top priority. Virulence attenuating combination therapy (VACT) is a pragmatic strategy to improve bacterial clearance, repurpose outmoded antibiotics, improve drug efficacy at lower doses, and reduce the evolution of resistance. In vitro and in vivo studies have shown that adding a quorum sensing inhibitor or an extracellular polymeric substance repressor to classical antibiotics synergistically improves antipseudomonal activity. This review highlights why VACT could specifically benefit cystic fibrosis patients harboring chronic P. aeruginosa infections, outlines the current landscape of synergistic combinations between virulence-targeting small-molecules and anti-pseudomonal drugs, and suggests future directions for VACT research.
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Affiliation(s)
- Elana Shaw
- Department of Chemistry , Emory University , 1515 Dickey Drive , Atlanta , Georgia 30322 , USA .
| | - William M Wuest
- Department of Chemistry , Emory University , 1515 Dickey Drive , Atlanta , Georgia 30322 , USA .
- Emory Antibiotic Resistance Center , Emory University School of Medicine , 201 Dowman Drive , Atlanta , Georgia 30322 , USA
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18
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Ma Y, Wang C, Li Y, Li J, Wan Q, Chen J, Tay FR, Niu L. Considerations and Caveats in Combating ESKAPE Pathogens against Nosocomial Infections. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:1901872. [PMID: 31921562 PMCID: PMC6947519 DOI: 10.1002/advs.201901872] [Citation(s) in RCA: 139] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 10/04/2019] [Indexed: 05/19/2023]
Abstract
ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) are among the most common opportunistic pathogens in nosocomial infections. ESKAPE pathogens distinguish themselves from normal ones by developing a high level of antibiotic resistance that involves multiple mechanisms. Contemporary therapeutic strategies which are potential options in combating ESKAPE bacteria need further investigation. Herein, a broad overview of the antimicrobial research on ESKAPE pathogens over the past five years is provided with prospective clinical applications.
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Affiliation(s)
- Yu‐Xuan Ma
- State Key Laboratory of Military StomatologyNational Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of ProsthodonticsSchool of StomatologyThe Fourth Military Medical University145 Changle West RoadXi'anShaanxi710032P. R. China
| | - Chen‐Yu Wang
- State Key Laboratory of Military StomatologyNational Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of ProsthodonticsSchool of StomatologyThe Fourth Military Medical University145 Changle West RoadXi'anShaanxi710032P. R. China
| | - Yuan‐Yuan Li
- State Key Laboratory of Military StomatologyNational Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of ProsthodonticsSchool of StomatologyThe Fourth Military Medical University145 Changle West RoadXi'anShaanxi710032P. R. China
| | - Jing Li
- State Key Laboratory of Military StomatologyNational Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of ProsthodonticsSchool of StomatologyThe Fourth Military Medical University145 Changle West RoadXi'anShaanxi710032P. R. China
| | - Qian‐Qian Wan
- State Key Laboratory of Military StomatologyNational Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of ProsthodonticsSchool of StomatologyThe Fourth Military Medical University145 Changle West RoadXi'anShaanxi710032P. R. China
| | - Ji‐Hua Chen
- State Key Laboratory of Military StomatologyNational Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of ProsthodonticsSchool of StomatologyThe Fourth Military Medical University145 Changle West RoadXi'anShaanxi710032P. R. China
| | - Franklin R. Tay
- State Key Laboratory of Military StomatologyNational Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of ProsthodonticsSchool of StomatologyThe Fourth Military Medical University145 Changle West RoadXi'anShaanxi710032P. R. China
- The Graduate SchoolAugusta University1430, John Wesley Gilbert DriveAugustaGA30912‐1129USA
| | - Li‐Na Niu
- State Key Laboratory of Military StomatologyNational Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of ProsthodonticsSchool of StomatologyThe Fourth Military Medical University145 Changle West RoadXi'anShaanxi710032P. R. China
- The Graduate SchoolAugusta University1430, John Wesley Gilbert DriveAugustaGA30912‐1129USA
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19
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Autoinducer-2 influences tetracycline resistance in Streptococcus suis by regulating the tet(M) gene via transposon Tn916. Res Vet Sci 2019; 128:269-274. [PMID: 31837515 DOI: 10.1016/j.rvsc.2019.12.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 10/31/2019] [Accepted: 12/03/2019] [Indexed: 01/08/2023]
Abstract
The concern over increasing resistance to tetracyclines (TCs), such as tetracycline and chlortetracycline, necessitates exploration of new approaches to combating infection in antimicrobial therapy. Given that bacteria use the chemical language of autoinducer 2 (AI-2) signaling molecules in order to communicate and regulate group behaviors, we asked whether the AI-2 signaling influence the tetracyclines antibiotics susceptibility in S. suis. Our present work demonstrated that MIC increased when exogenous AI-2 was added, when compared to the wild type strain. When grown in the presence of sub-MIC of antibiotics, it has been shown that exogenous AI-2 increases growth rate and biofilm formation. These results suggest that the TCs resistance in S. suis could involve a signaling mechanism. Base on the above observations, transcriptomic analyses showed significant differences in the expression of tet(M) of tetracyclines resistance genes, as well as differences in Tn916 transposon related genes transcription, as judged by RT-PCR. Our results provide strong evidence that AI-2 signaling molecules is may involve in TCs antibiotic resistance in S. suis by regulating tet(M) gene via Tn916 transposon. This study may suggest that targeting AI-2 signaling in bacteria could represent an alternative approach in antimicrobial therapy.
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20
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Nogueira F, Sharghi S, Kuchler K, Lion T. Pathogenetic Impact of Bacterial-Fungal Interactions. Microorganisms 2019; 7:microorganisms7100459. [PMID: 31623187 PMCID: PMC6843596 DOI: 10.3390/microorganisms7100459] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 09/20/2019] [Accepted: 10/15/2019] [Indexed: 12/17/2022] Open
Abstract
Polymicrobial infections are of paramount importance because of the potential severity of clinical manifestations, often associated with increased resistance to antimicrobial treatment. The intricate interplay with the host and the immune system, and the impact on microbiome imbalance, are of importance in this context. The equilibrium of microbiota in the human host is critical for preventing potential dysbiosis and the ensuing development of disease. Bacteria and fungi can communicate via signaling molecules, and produce metabolites and toxins capable of modulating the immune response or altering the efficacy of treatment. Most of the bacterial–fungal interactions described to date focus on the human fungal pathogen Candida albicans and different bacteria. In this review, we discuss more than twenty different bacterial–fungal interactions involving several clinically important human pathogens. The interactions, which can be synergistic or antagonistic, both in vitro and in vivo, are addressed with a focus on the quorum-sensing molecules produced, the response of the immune system, and the impact on clinical outcome.
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Affiliation(s)
- Filomena Nogueira
- CCRI-St. Anna Children's Cancer Research Institute, Vienna 1090, Austria.
- Labdia-Labordiagnostik GmbH, Vienna 1090, Austria.
- Center of Medical Biochemistry, Max Perutz Labs, Campus Vienna Biocenter, Medical University of Vienna, Vienna 1030, Austria.
| | - Shirin Sharghi
- CCRI-St. Anna Children's Cancer Research Institute, Vienna 1090, Austria.
- Labdia-Labordiagnostik GmbH, Vienna 1090, Austria.
- Center of Medical Biochemistry, Max Perutz Labs, Campus Vienna Biocenter, Medical University of Vienna, Vienna 1030, Austria.
| | - Karl Kuchler
- Center of Medical Biochemistry, Max Perutz Labs, Campus Vienna Biocenter, Medical University of Vienna, Vienna 1030, Austria.
| | - Thomas Lion
- CCRI-St. Anna Children's Cancer Research Institute, Vienna 1090, Austria.
- Labdia-Labordiagnostik GmbH, Vienna 1090, Austria.
- Department of Pediatrics, Medical University of Vienna, Vienna 1090, Austria.
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21
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Reen FJ, McGlacken GP, O'Gara F. The expanding horizon of alkyl quinolone signalling and communication in polycellular interactomes. FEMS Microbiol Lett 2019; 365:4953739. [PMID: 29718276 DOI: 10.1093/femsle/fny076] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 03/25/2018] [Indexed: 02/07/2023] Open
Abstract
Population dynamics within natural ecosystems is underpinned by microbial diversity and the heterogeneity of host-microbe and microbe-microbe interactions. Small molecule signals that intersperse between species have been shown to govern many virulence-related processes in established and emerging pathogens. Understanding the capacity of microbes to decode diverse languages and adapt to the presence of 'non-self' cells will provide an important new direction to the understanding of the 'polycellular' interactome. Alkyl quinolones (AQs) have been described in the ESKAPE pathogen Pseudomonas aeruginosa, the primary agent associated with mortality in patients with cystic fibrosis and the third most prevalent nosocomial pathogen worldwide. The role of these molecules in governing the physiology and virulence of P. aeruginosa and other pathogens has received considerable attention, while a role in interspecies and interkingdom communication has recently emerged. Herein we discuss recent advances in our understanding of AQ signalling and communication in the context of microbe-microbe and microbe-host interactions. The integrated knowledge from these systems-based investigations will facilitate the development of new therapeutics based on the AQ framework that serves to disarm the pathogenesis of P. aeruginosa and competing pathogens.
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Affiliation(s)
- F Jerry Reen
- School of Microbiology, University College Cork, Cork, Ireland
| | - Gerard P McGlacken
- School of Chemistry and Analytical & Biological Chemistry Research Facility (ABCRF), University College Cork, Ireland
| | - Fergal O'Gara
- BIOMERIT Research Centre, School of Microbiology, University College Cork, Cork, Ireland
- Human Microbiome Programme, School of Pharmacy and Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Perth, WA 6102, USA
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22
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Thierbach S, Wienhold M, Fetzner S, Hennecke U. Synthesis and biological activity of methylated derivatives of the Pseudomonas metabolites HHQ, HQNO and PQS. Beilstein J Org Chem 2019; 15:187-193. [PMID: 30745993 PMCID: PMC6350858 DOI: 10.3762/bjoc.15.18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Accepted: 01/02/2019] [Indexed: 01/24/2023] Open
Abstract
Selectively methylated analogues of naturally occurring 2-heptyl-4(1H)-quinolones, which are alkaloids common within the Rutaceae family and moreover are associated with quorum sensing and virulence of the human pathogen Pseudomonas aeruginosa, have been prepared. While the synthesis by direct methylation was successful for 3-unsubstituted 2-heptyl-4(1H)-quinolones, methylated derivatives of the Pseudomonas quinolone signal (PQS) were synthesized from 3-iodinated quinolones by methylation and iodine–metal exchange/oxidation. The two N- and O-methylated derivatives of the PQS showed strong quorum sensing activity comparable to that of PQS itself. Staphylococcus aureus, another pathogenic bacterium often co-occurring with P. aeruginosa especially in the lung of cystic fibrosis patients, was inhibited in planktonic growth and cellular respiration by the 4-O-methylated derivatives of HQNO and HHQ, respectively.
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Affiliation(s)
- Sven Thierbach
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Corrensstr. 3, 48149 Münster, Germany
| | - Max Wienhold
- Organic Chemistry Institute, University of Münster, Corrensstr. 40, 48149 Münster, Germany
| | - Susanne Fetzner
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Corrensstr. 3, 48149 Münster, Germany
| | - Ulrich Hennecke
- Organic Chemistry Institute, University of Münster, Corrensstr. 40, 48149 Münster, Germany.,Organic Chemistry Research Group, Departments of Chemistry and Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel, Belgium
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23
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Wu X, Zheng LL, Zhao LP, Zhu CF, Li YG. Gold-catalyzed cyclization of 1-(2′-azidoaryl) propynols: synthesis of polysubstituted 4-quinolones. Chem Commun (Camb) 2019; 55:14769-14772. [DOI: 10.1039/c9cc06652g] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
α-Imino gold carbene intermediate is produced from 1-(2′-azidoaryl) propynols, which triggers a 1,2-carbon migration and is converted to 2,3-disubstituted 4-quinolones. The reaction works under mild conditions and tolerates various functional groups.
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Affiliation(s)
- Xiang Wu
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering
- Hefei University of Technology
- 193 Tunxi Road
- Hefei 230009
- China
| | - Lang-Lang Zheng
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering
- Hefei University of Technology
- 193 Tunxi Road
- Hefei 230009
- China
| | - Li-Ping Zhao
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering
- Hefei University of Technology
- 193 Tunxi Road
- Hefei 230009
- China
| | - Cheng-Feng Zhu
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering
- Hefei University of Technology
- 193 Tunxi Road
- Hefei 230009
- China
| | - You-Gui Li
- Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction Engineering, School of Chemistry and Chemical Engineering
- Hefei University of Technology
- 193 Tunxi Road
- Hefei 230009
- China
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24
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Xu XJ, Zeng T, Huang ZX, Xu XF, Lin J, Chen WM. Synthesis and Biological Evaluation of Cajaninstilbene Acid and Amorfrutins A and B as Inhibitors of the Pseudomonas aeruginosa Quorum Sensing System. JOURNAL OF NATURAL PRODUCTS 2018; 81:2621-2629. [PMID: 30444360 DOI: 10.1021/acs.jnatprod.8b00315] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The quorum sensing (QS) system inhibitors of Pseudomonas aeruginosa are thought to attenuate bacterial pathogenicity and drug resistance by inhibiting biofilm formation and the production of virulence factors. In this study, a synthetic approach to the natural products cajaninstilbene acid (1) and amorfrutins A (2) and B (3) has been developed and was characterized by the Heck reaction, which was used to obtain the stilbene core and a Pinick oxidation to give the O-hydroxybenzoic acid. The biological activities of these compounds against the P. aeruginosa quorum sensing systems were evaluated. Amorfrutin B (3) showed promising antibiofilm activity against P. aeruginosa PAO1 with a biofilm inhibition ratio of 50.3 ± 2.7. Three lacZ reporter strains were constructed to identify the effects of compound 3 on different QS systems. Suppression efficacy of compound 3 on the expression of lasB-lacZ and pqsA-lacZ as well as on the production of their corresponding virulence factors elastase and pyocyanin was observed.
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Affiliation(s)
- Xing-Jun Xu
- College of Pharmacy , Jinan University , Guangzhou 510632 , People's Republic of China
| | - Ting Zeng
- College of Pharmacy , Jinan University , Guangzhou 510632 , People's Republic of China
| | - Zhi-Xing Huang
- College of Pharmacy , Jinan University , Guangzhou 510632 , People's Republic of China
| | - Xiao-Fang Xu
- College of Pharmacy , Jinan University , Guangzhou 510632 , People's Republic of China
| | - Jing Lin
- College of Pharmacy , Jinan University , Guangzhou 510632 , People's Republic of China
| | - Wei-Min Chen
- College of Pharmacy , Jinan University , Guangzhou 510632 , People's Republic of China
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25
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Geddis SM, Coroama T, Forrest S, Hodgkinson JT, Welch M, Spring DR. Synthesis and biological evaluation of 1,2-disubsubstituted 4-quinolone analogues of Pseudonocardia sp. natural products. Beilstein J Org Chem 2018; 14:2680-2688. [PMID: 30410629 PMCID: PMC6204808 DOI: 10.3762/bjoc.14.245] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 10/10/2018] [Indexed: 11/23/2022] Open
Abstract
A series of analogues of Pseudonocardia sp. natural products were synthesized, which have been reported to possess potent antibacterial activity against Helicobacter pylori and induce growth defects in Escherichia coli and Staphylococcus aureus. Taking inspiration from a methodology used in our total synthesis of natural products, we applied this methodology to access analogues possessing bulky N-substituents, traditionally considered to be challenging scaffolds. Screening of the library provided valuable insights into the structure-activity relationship of the bacterial growth defects, and suggested that selectivity between bacterial species should be attainable. Furthermore, a structurally related series of analogues was observed to inhibit production of the virulence factor pyocyanin in the human pathogen Pseudomonas aeruginosa, which may be a result of their similarity to the Pseudomonas quinolone signal (PQS) quorum sensing autoinducer. This provided new insights regarding the effect of N-substitution in PQS analogues, which has been hitherto underexplored.
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Affiliation(s)
- Stephen M Geddis
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Teodora Coroama
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Suzanne Forrest
- Department of Biochemistry, University of Cambridge, 80 Tennis Road, Cambridge, CB2 1GA, UK
| | - James T Hodgkinson
- Leicester Institute of Structural and Chemical Biology, and Department of Chemistry, University of Leicester, George Porter Building, University Road, Leicester, LE1 7RH, UK
| | - Martin Welch
- Department of Biochemistry, University of Cambridge, 80 Tennis Road, Cambridge, CB2 1GA, UK
| | - David R Spring
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
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Lakemeyer M, Zhao W, Mandl FA, Hammann P, Sieber SA. Thinking Outside the Box-Novel Antibacterials To Tackle the Resistance Crisis. Angew Chem Int Ed Engl 2018; 57:14440-14475. [PMID: 29939462 DOI: 10.1002/anie.201804971] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Indexed: 12/13/2022]
Abstract
The public view on antibiotics as reliable medicines changed when reports about "resistant superbugs" appeared in the news. While reasons for this resistance development are easily spotted, solutions for re-establishing effective antibiotics are still in their infancy. This Review encompasses several aspects of the antibiotic development pipeline from very early strategies to mature drugs. An interdisciplinary overview is given of methods suitable for mining novel antibiotics and strategies discussed to unravel their modes of action. Select examples of antibiotics recently identified by using these platforms not only illustrate the efficiency of these measures, but also highlight promising clinical candidates with therapeutic potential. Furthermore, the concept of molecules that disarm pathogens by addressing gatekeepers of virulence will be covered. The Review concludes with an evaluation of antibacterials currently in clinical development. Overall, this Review aims to connect select innovative antimicrobial approaches to stimulate interdisciplinary partnerships between chemists from academia and industry.
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Affiliation(s)
- Markus Lakemeyer
- Department of Chemistry, Chair of Organic Chemistry II, Center for Integrated Protein Science (CIPSM), Technische Universität München, Lichtenbergstrasse 4, 85747, Garching, Germany
| | - Weining Zhao
- Department of Chemistry, Chair of Organic Chemistry II, Center for Integrated Protein Science (CIPSM), Technische Universität München, Lichtenbergstrasse 4, 85747, Garching, Germany
| | - Franziska A Mandl
- Department of Chemistry, Chair of Organic Chemistry II, Center for Integrated Protein Science (CIPSM), Technische Universität München, Lichtenbergstrasse 4, 85747, Garching, Germany
| | - Peter Hammann
- R&D Therapeutic Area Infectious Diseases, Sanofi-Aventis (Deutschland) GmbH, Industriepark Höchst, 65926, Frankfurt am Main, Germany
| | - Stephan A Sieber
- Department of Chemistry, Chair of Organic Chemistry II, Center for Integrated Protein Science (CIPSM), Technische Universität München, Lichtenbergstrasse 4, 85747, Garching, Germany
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27
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Lakemeyer M, Zhao W, Mandl FA, Hammann P, Sieber SA. Über bisherige Denkweisen hinaus - neue Wirkstoffe zur Überwindung der Antibiotika-Krise. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201804971] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Markus Lakemeyer
- Fakultät für Chemie; Lehrstuhl für Organische Chemie II, Center for Integrated Protein Science (CIPSM); Technische Universität München; Lichtenbergstraße 4 85747 Garching Deutschland
| | - Weining Zhao
- Fakultät für Chemie; Lehrstuhl für Organische Chemie II, Center for Integrated Protein Science (CIPSM); Technische Universität München; Lichtenbergstraße 4 85747 Garching Deutschland
| | - Franziska A. Mandl
- Fakultät für Chemie; Lehrstuhl für Organische Chemie II, Center for Integrated Protein Science (CIPSM); Technische Universität München; Lichtenbergstraße 4 85747 Garching Deutschland
| | - Peter Hammann
- R&D Therapeutic Area Infectious Diseases; Sanofi-Aventis (Deutschland) GmbH; Industriepark Höchst 65926 Frankfurt am Main Deutschland
| | - Stephan A. Sieber
- Fakultät für Chemie; Lehrstuhl für Organische Chemie II, Center for Integrated Protein Science (CIPSM); Technische Universität München; Lichtenbergstraße 4 85747 Garching Deutschland
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28
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Li C, Liang J, Yang Y, Pu J, Hou LA. Novel insights into the role of Pseudomonas quinolone signal in the control of reverse osmosis membrane biofouling. J Memb Sci 2018. [DOI: 10.1016/j.memsci.2018.06.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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29
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Torres-Fuentes C, Pastor-Cavada E, Cano R, Kandil D, Shanahan R, Juan R, Shaban H, McGlacken GP, Schellekens H. Quinolones Modulate Ghrelin Receptor Signaling: Potential for a Novel Small Molecule Scaffold in the Treatment of Cachexia. Int J Mol Sci 2018; 19:E1605. [PMID: 29848961 PMCID: PMC6032407 DOI: 10.3390/ijms19061605] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 05/21/2018] [Accepted: 05/22/2018] [Indexed: 02/06/2023] Open
Abstract
Cachexia is a metabolic wasting disorder characterized by progressive weight loss, muscle atrophy, fatigue, weakness, and appetite loss. Cachexia is associated with almost all major chronic illnesses including cancer, heart failure, obstructive pulmonary disease, and kidney disease and significantly impedes treatment outcome and therapy tolerance, reducing physical function and increasing mortality. Current cachexia treatments are limited and new pharmacological strategies are needed. Agonists for the growth hormone secretagogue (GHS-R1a), or ghrelin receptor, prospectively regulate the central regulation of appetite and growth hormone secretion, and therefore have tremendous potential as cachexia therapeutics. Non-peptide GHS-R1a agonists are of particular interest, especially given the high gastrointestinal degradation of peptide-based structures, including that of the endogenous ligand, ghrelin, which has a half-life of only 30 min. However, few compounds have been reported in the literature as non-peptide GHS-R1a agonists. In this paper, we investigate the in vitro potential of quinolone compounds to modulate the GHS-R1a in both transfected human cells and mouse hypothalamic cells. These chemically synthesized compounds demonstrate a promising potential as GHS-R1a agonists, shown by an increased intracellular calcium influx. Further studies are now warranted to substantiate and exploit the potential of these novel quinolone-based compounds as orexigenic therapeutics in conditions of cachexia and other metabolic and eating disorders.
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Affiliation(s)
| | | | - Rafael Cano
- School of Chemistry and the Analytical and Biological Chemistry Research Facility (ABCRF), University College Cork, T12 YT20 Cork, Ireland.
| | - Dalia Kandil
- Food for Health Ireland, University College Cork, T12 YT20 Cork, Ireland.
- Department of Anatomy and Neuroscience, University College Cork, T12 YT20 Cork, Ireland.
| | - Rachel Shanahan
- School of Chemistry and the Analytical and Biological Chemistry Research Facility (ABCRF), University College Cork, T12 YT20 Cork, Ireland.
| | - Rocio Juan
- Plant Biology and Ecology Department, Seville University, 41012 Seville, Spain.
| | - Hamdy Shaban
- Food for Health Ireland, University College Cork, T12 YT20 Cork, Ireland.
| | - Gerard P McGlacken
- School of Chemistry and the Analytical and Biological Chemistry Research Facility (ABCRF), University College Cork, T12 YT20 Cork, Ireland.
| | - Harriët Schellekens
- APC Microbiome Ireland, University College Cork, T12 YT20 Cork, Ireland.
- Food for Health Ireland, University College Cork, T12 YT20 Cork, Ireland.
- Department of Anatomy and Neuroscience, University College Cork, T12 YT20 Cork, Ireland.
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30
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Boursier ME, Manson DE, Combs JB, Blackwell HE. A comparative study of non-native N-acyl l-homoserine lactone analogs in two Pseudomonas aeruginosa quorum sensing receptors that share a common native ligand yet inversely regulate virulence. Bioorg Med Chem 2018; 26:5336-5342. [PMID: 29793752 DOI: 10.1016/j.bmc.2018.05.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 05/07/2018] [Accepted: 05/13/2018] [Indexed: 10/16/2022]
Abstract
Certain bacteria can coordinate group behaviors via a chemical communication system known as quorum sensing (QS). Gram-negative bacteria typically use N-acyl l-homoserine lactone (AHL) signals and their cognate intracellular LuxR-type receptors for QS. The opportunistic pathogen Pseudomonas aeruginosa has a relatively complex QS circuit in which two of its LuxR-type receptors, LasR and QscR, are activated by the same natural signal, N-(3-oxo)-dodecanoyl l-homoserine lactone. Intriguingly, once active, LasR activates virulence pathways in P. aeruginosa, while activated QscR can inactivate LasR and thus repress virulence. We have a limited understanding of the structural features of AHLs that engender either agonistic activity in both receptors or receptor-selective activity. Compounds with the latter activity profile could prove especially useful tools to tease out the roles of these two receptors in virulence regulation. A small collection of AHL analogs was assembled and screened in cell-based reporter assays for activity in both LasR and QscR. We identified several structural motifs that bias ligand activation towards each of the two receptors. These findings will inform the development of new synthetic ligands for LasR and QscR with improved potencies and selectivities.
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Affiliation(s)
- Michelle E Boursier
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, WI 53706, USA
| | - Daniel E Manson
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, WI 53706, USA
| | - Joshua B Combs
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, WI 53706, USA
| | - Helen E Blackwell
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, WI 53706, USA.
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