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Wang J, Zhang M, Li C, Liu M, Qi Y, Xie X, Zhou C, Ma L. A novel cathelicidin TS-CATH derived from Thamnophis sirtalis combats drug-resistant gram-negative bacteria in vitro and in vivo. Comput Struct Biotechnol J 2024; 23:2388-2406. [PMID: 38882682 PMCID: PMC11176561 DOI: 10.1016/j.csbj.2024.05.020] [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: 12/28/2023] [Revised: 05/08/2024] [Accepted: 05/13/2024] [Indexed: 06/18/2024] Open
Abstract
Antimicrobial peptides are promising therapeutic agents for treating drug-resistant bacterial disease due to their broad-spectrum antimicrobial activity and decreased susceptibility to evolutionary resistance. In this study, three novel cathelicidin antimicrobial peptides were identified from Thamnophis sirtalis, Balaenoptera musculus, and Lipotes vexillifer by protein database mining and sequence alignment and were subsequently named TS-CATH, BM-CATH, and LV-CATH, respectively. All three peptides exhibited satisfactory antibacterial activity and broad antibacterial spectra against clinically isolated E. coli, P. aeruginosa, K. pneumoniae, and A. baumannii in vitro. Among them, TS-CATH displayed the best antimicrobial/bactericidal activity, with a rapid elimination efficiency against the tested drug-resistant gram-negative bacteria within 20 min, and exhibited the lowest cytotoxicity toward mammalian cells. Furthermore, TS-CATH effectively enhanced the survival rate of mice with ceftazidime-resistant E. coli bacteremia and promoted wound healing in meropenem-resistant P. aeruginosa infection. These results were achieved through the eradication of bacterial growth in target organs and wounds, further inhibiting the systemic dissemination of bacteria and the inflammatory response. TS-CATH exhibited direct antimicrobial activity by damaging the inner and outer membranes, resulting in leakage of the bacterial contents at super-MICs. Moreover, TS-CATH disrupted the bacterial respiratory chain, which inhibited ATP synthesis and induced ROS formation, significantly contributing to its antibacterial efficacy at sub-MICs. Overall, TS-CATH has potential for use as an antibacterial agent.
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Affiliation(s)
- Jian Wang
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Meina Zhang
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Chao Li
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Mengyuan Liu
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Yixin Qi
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Xiaolin Xie
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Changlin Zhou
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Lingman Ma
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
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2
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Li W, Tao Z, Zhou M, Jiang H, Wang L, Ji B, Zhao Y. Antibiotic adjuvants against multidrug-resistant Gram-negative bacteria: important component of future antimicrobial therapy. Microbiol Res 2024; 287:127842. [PMID: 39032266 DOI: 10.1016/j.micres.2024.127842] [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: 04/24/2024] [Revised: 07/13/2024] [Accepted: 07/14/2024] [Indexed: 07/23/2024]
Abstract
The swift emergence and propagation of multidrug-resistant (MDR) bacterial pathogens constitute a tremendous global health crisis. Among these pathogens, the challenge of antibiotic resistance in Gram-negative bacteria is particularly pressing due to their distinctive structure, such as highly impermeable outer membrane, overexpressed efflux pumps, and mutations. Several strategies have been documented to combat MDR Gram-negative bacteria, including the structural modification of existing antibiotics, the development of antimicrobial adjuvants, and research on novel targets that MDR bacteria are sensitive to. Drugs functioning as adjuvants to mitigate resistance to existing antibiotics may play a pivotal role in future antibacterial therapy strategies. In this review, we provide a brief overview of potential antibacterial adjuvants against Gram-negative bacteria and their mechanisms of action, and discuss the application prospects and potential for bacterial resistance to these adjuvants, along with strategies to reduce this risk.
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Affiliation(s)
- Wenwen Li
- School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning Province 110016, PR China
| | - Zhen Tao
- School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning Province 110016, PR China
| | - Motan Zhou
- School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning Province 110016, PR China
| | - Huilin Jiang
- School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning Province 110016, PR China
| | - Liudi Wang
- School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning Province 110016, PR China
| | - Bingjie Ji
- School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning Province 110016, PR China
| | - Yongshan Zhao
- School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning Province 110016, PR China.
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3
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Samgane G, Karaçam S, Tunçer Çağlayan S. Unveiling the synergistic potency of chlorhexidine and azithromycin in combined action. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2024; 397:5975-5987. [PMID: 38376540 PMCID: PMC11329591 DOI: 10.1007/s00210-024-03010-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 02/12/2024] [Indexed: 02/21/2024]
Abstract
The growing challenge of antibiotic resistance necessitates novel approaches for combating bacterial infections. This study explores the distinctive synergy between chlorhexidine, an antiseptic and disinfectant agent, and azithromycin, a macrolide antibiotic, in their impact on bacterial growth and virulence factors using Escherichia coli strain Crooks (ATCC 8739) as a model. Our findings reveal that the chlorhexidine and azithromycin combination demonstrates enhanced anti-bacterial effects compared to individual treatments. Intriguingly, the combination induced oxidative stress, decreased flagellin expression, impaired bacterial motility, and enhanced bacterial autoaggregation. Notably, the combined treatment also demonstrated a substantial reduction in bacterial adherence to colon epithelial cells and downregulated NF-κB in the epithelial cells. In conclusion, these results shed light on the potential of the chlorhexidine and azithromycin synergy as a compelling strategy to address the rising challenge of antibiotic resistance and may pave the way for innovative therapeutic interventions in tackling bacterial infections.
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Affiliation(s)
- Gizem Samgane
- Department of Biotechnology, Bilecik Şeyh Edebali University, Bilecik, 11100, Turkey
| | - Sevinç Karaçam
- Department of Biotechnology, Bilecik Şeyh Edebali University, Bilecik, 11100, Turkey
- Central Research and Application Laboratory, Bilecik Şeyh Edebali University, Bilecik, 11100, Turkey
| | - Sinem Tunçer Çağlayan
- Department of Medical Services and Techniques, Vocational School of Health Services, Bilecik Şeyh Edebali University, Pelitözü Mah. Fatih Sultan Mehmet Bulvarı No:27, Bilecik, 11100, Turkey.
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4
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Bepler T, Barrera MD, Rooney MT, Xiong Y, Kuang H, Goodell E, Goodwin MJ, Harbron E, Fu R, Mihailescu M, Narayanan A, Cotten ML. Antiviral activity of the host defense peptide piscidin 1: investigating a membrane-mediated mode of action. Front Chem 2024; 12:1379192. [PMID: 38988727 PMCID: PMC11233706 DOI: 10.3389/fchem.2024.1379192] [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: 01/30/2024] [Accepted: 05/08/2024] [Indexed: 07/12/2024] Open
Abstract
Outbreaks of viral diseases are on the rise, fueling the search for antiviral therapeutics that act on a broad range of viruses while remaining safe to human host cells. In this research, we leverage the finding that the plasma membranes of host cells and the lipid bilayers surrounding enveloped viruses differ in lipid composition. We feature Piscidin 1 (P1), a cationic host defense peptide (HDP) that has antimicrobial effects and membrane activity associated with its N-terminal region where a cluster of aromatic residues and copper-binding motif reside. While few HDPs have demonstrated antiviral activity, P1 acts in the micromolar range against several enveloped viruses that vary in envelope lipid composition. Notably, it inhibits HIV-1, a virus that has an envelope enriched in cholesterol, a lipid associated with higher membrane order and stability. Here, we first document through plaque assays that P1 boasts strong activity against SARS-CoV-2, which has an envelope low in cholesterol. Second, we extend previous studies done with homogeneous bilayers and devise cholesterol-containing zwitterionic membranes that contain the liquid disordered (Ld; low in cholesterol) and ordered (Lo, rich in cholesterol) phases. Using dye leakage assays and cryo-electron microscopy on vesicles, we show that P1 has dramatic permeabilizing capability on the Lo/Ld, an effect matched by a strong ability to aggregate, fuse, and thin the membranes. Differential scanning calorimetry and NMR experiments demonstrate that P1 mixes the lipid content of vesicles and alters the stability of the Lo. Structural studies by NMR indicate that P1 interacts with the Lo/Ld by folding into an α-helix that lies parallel to the membrane surface. Altogether, these results show that P1 is more disruptive to phase-separated than homogenous cholesterol-containing bilayers, suggesting an ability to target domain boundaries. Overall, this multi-faceted research highlights how a peptide that interacts strongly with membranes through an aromatic-rich N-terminal motif disrupt viral envelope mimics. This represents an important step towards the development of novel peptides with broad-spectrum antiviral activity.
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Affiliation(s)
- Tristan Bepler
- New York Structural Biology Center, New York, NY, United States
| | - Michael D. Barrera
- School of Systems Biology, George Mason University, Manassas, VA, United States
| | - Mary T. Rooney
- Department of Applied Science, William & Mary, Williamsburg, VA, United States
- Department of Chemistry, Hofstra University, Hempstead, NY, United States
| | - Yawei Xiong
- Department of Applied Science, William & Mary, Williamsburg, VA, United States
| | - Huihui Kuang
- New York Structural Biology Center, New York, NY, United States
| | - Evan Goodell
- Department of Applied Science, William & Mary, Williamsburg, VA, United States
| | - Matthew J. Goodwin
- Department of Chemistry, William & Mary, Williamsburg, VA, United States
| | - Elizabeth Harbron
- Department of Chemistry, William & Mary, Williamsburg, VA, United States
| | - Riqiang Fu
- National High Magnetic Field Laboratory, Tallahassee, FL, United States
| | - Mihaela Mihailescu
- Institute for Bioscience and Biotechnology Research, Rockville, MD, United States
| | - Aarthi Narayanan
- Department of Biology, George Mason University, Manassas, VA, United States
| | - Myriam L. Cotten
- Department of Applied Science, William & Mary, Williamsburg, VA, United States
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR, United States
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5
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Chen C, Shi J, Wang D, Kong P, Wang Z, Liu Y. Antimicrobial peptides as promising antibiotic adjuvants to combat drug-resistant pathogens. Crit Rev Microbiol 2024; 50:267-284. [PMID: 36890767 DOI: 10.1080/1040841x.2023.2186215] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 07/19/2022] [Accepted: 10/26/2022] [Indexed: 03/10/2023]
Abstract
The widespread antimicrobial resistance (AMR) calls for the development of new antimicrobial strategies. Antibiotic adjuvant rescues antibiotic activity and increases the life span of the antibiotics, representing a more productive, timely, and cost-effective strategy in fighting drug-resistant pathogens. Antimicrobial peptides (AMPs) from synthetic and natural sources are considered new-generation antibacterial agents. Besides their direct antimicrobial activity, growing evidence shows that some AMPs effectively enhance the activity of conventional antibiotics. The combinations of AMPs and antibiotics display an improved therapeutic effect on antibiotic-resistant bacterial infections and minimize the emergence of resistance. In this review, we discuss the value of AMPs in the age of resistance, including modes of action, limiting evolutionary resistance, and their designing strategies. We summarise the recent advances in combining AMPs and antibiotics against antibiotic-resistant pathogens, as well as their synergistic mechanisms. Lastly, we highlight the challenges and opportunities associated with the use of AMPs as potential antibiotic adjuvants. This will shed new light on the deployment of synergistic combinations to address the AMR crisis.
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Affiliation(s)
- Chen Chen
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Jingru Shi
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Dejuan Wang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Pan Kong
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Zhiqiang Wang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, Ministry of Education of China, Yangzhou University, Yangzhou, China
| | - Yuan Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Institute of Comparative Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, Ministry of Education of China, Yangzhou University, Yangzhou, China
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6
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Yang L, Gao Y, Zhang J, Tian C, Lin F, Song D, Zhou L, Peng J, Guo G. Antimicrobial peptide DvAMP combats carbapenem-resistant Acinetobacter baumannii infection. Int J Antimicrob Agents 2024; 63:107106. [PMID: 38325724 DOI: 10.1016/j.ijantimicag.2024.107106] [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: 08/16/2023] [Revised: 12/26/2023] [Accepted: 01/29/2024] [Indexed: 02/09/2024]
Abstract
Carbapenem-resistant Acinetobacter baumannii (CRAB), an important opportunistic pathogen, is a major cause of healthcare-associated infections. The polymyxins (colistin and polymyxin B) are the last line of defense in the treatment of CRAB infections, and there is an urgent need to develop novel alternative therapeutic strategies. In this study, we found that the antimicrobial peptide DvAMP exhibited satisfactory antibacterial and antibiofilm activity against CRAB. In addition, DvAMP showed tolerable stability in salt ions and serum and exhibited low toxicity in vivo. Investigation of the underlying mechanism demonstrated that DvAMP disrupts cell membrane structural integrity and specifically binds to exogenous lipopolysaccharides (LPS) and phospholipids (PG/CL), resulting in increased membrane permeability and dissipating proton motive force (PMF), further reducing intracellular ATP levels and inducing ROS accumulation, leading to bacterial death. Furthermore, DvAMP therapy efficiently improved survival rates and decreased the bacterial load in the lungs of mice in a mouse pneumonia model, showing that DvAMP administration reduced CRAB susceptibility to lung infection. These results indicate that the peptide DvAMP is a promising alternative therapeutic agent to combat CRAB infection.
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Affiliation(s)
- Longbing Yang
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China; Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, China; Translational Medicine Research Center, Guizhou Medical University, Guiyang, China
| | - Yongfei Gao
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China
| | - Jin Zhang
- Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, China; School of Public Health, Guizhou Medical University, Guiyang, China
| | - Chunren Tian
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China
| | - Fei Lin
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China
| | - Dongxu Song
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China; Translational Medicine Research Center, Guizhou Medical University, Guiyang, China
| | - Luoxiong Zhou
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China; School of Public Health, Guizhou Medical University, Guiyang, China
| | - Jian Peng
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China; Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, China.
| | - Guo Guo
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China; Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, China; Translational Medicine Research Center, Guizhou Medical University, Guiyang, China.
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7
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Heo HY, Zou G, Baek S, Kim J, Mylonakis E, Ausubel FM, Gao H, Kim W. A Methylazanediyl Bisacetamide Derivative Sensitizes Staphylococcus aureus Persisters to a Combination of Gentamicin And Daptomycin. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2306112. [PMID: 38126676 PMCID: PMC10916567 DOI: 10.1002/advs.202306112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 12/01/2023] [Indexed: 12/23/2023]
Abstract
Infections caused by Staphylococcus aureus, notably methicillin-resistant S. aureus (MRSA), pose treatment challenges due to its ability to tolerate antibiotics and develop antibiotic resistance. The former, a mechanism independent of genetic changes, allows bacteria to withstand antibiotics by altering metabolic processes. Here, a potent methylazanediyl bisacetamide derivative, MB6, is described, which selectively targets MRSA membranes over mammalian membranes without observable resistance development. Although MB6 is effective against growing MRSA cells, its antimicrobial activity against MRSA persisters is limited. Nevertheless, MB6 significantly potentiates the bactericidal activity of gentamicin against MRSA persisters by facilitating gentamicin uptake. In addition, MB6 in combination with daptomycin exhibits enhanced anti-persister activity through mutual reinforcement of their membrane-disrupting activities. Crucially, the "triple" combination of MB6, gentamicin, and daptomycin exhibits a marked enhancement in the killing of MRSA persisters compared to individual components or any double combinations. These findings underscore the potential of MB6 to function as a potent and selective membrane-active antimicrobial adjuvant to enhance the efficacy of existing antibiotics against persister cells. The molecular mechanisms of MB6 elucidated in this study provide valuable insights for designing anti-persister adjuvants and for developing new antimicrobial combination strategies to overcome the current limitations of antibiotic treatments.
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Affiliation(s)
- Hee Young Heo
- College of PharmacyGraduate School of Pharmaceutical SciencesEwha Womans UniversitySeoul03760Republic of Korea
| | - Guijin Zou
- Institute of High Performance Computing (IHPC)Agency for ScienceTechnology and Research (A*STAR)Singapore138632Republic of Singapore
| | - Seongeun Baek
- College of PharmacyGraduate School of Pharmaceutical SciencesEwha Womans UniversitySeoul03760Republic of Korea
| | - Jae‐Seok Kim
- Department of Laboratory MedicineKangdong Sacred Heart HospitalHallym University College of MedicineSeoul05355Republic of Korea
| | | | - Frederick M. Ausubel
- Department of Molecular BiologyMassachusetts General HospitalBostonMA02114USA
- Department of GeneticsHarvard Medical SchoolBostonMA02115USA
| | - Huajian Gao
- Institute of High Performance Computing (IHPC)Agency for ScienceTechnology and Research (A*STAR)Singapore138632Republic of Singapore
- School of Mechanical and Aerospace EngineeringCollege of EngineeringNanyang Technological UniversitySingapore639789Republic of Singapore
| | - Wooseong Kim
- College of PharmacyGraduate School of Pharmaceutical SciencesEwha Womans UniversitySeoul03760Republic of Korea
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8
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Ji S, An F, Zhang T, Lou M, Guo J, Liu K, Zhu Y, Wu J, Wu R. Antimicrobial peptides: An alternative to traditional antibiotics. Eur J Med Chem 2024; 265:116072. [PMID: 38147812 DOI: 10.1016/j.ejmech.2023.116072] [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: 10/16/2023] [Revised: 12/04/2023] [Accepted: 12/17/2023] [Indexed: 12/28/2023]
Abstract
As antibiotic-resistant bacteria and genes continue to emerge, the identification of effective alternatives to traditional antibiotics has become a pressing issue. Antimicrobial peptides are favored for their safety, low residue, and low resistance properties, and their unique antimicrobial mechanisms show significant potential in combating antibiotic resistance. However, the high production cost and weak activity of antimicrobial peptides limit their application. Moreover, traditional laboratory methods for identifying and designing new antimicrobial peptides are time-consuming and labor-intensive, hindering their development. Currently, novel technologies, such as artificial intelligence (AI) are being employed to develop and design new antimicrobial peptide resources, offering new opportunities for the advancement of antimicrobial peptides. This article summarizes the basic characteristics and antimicrobial mechanisms of antimicrobial peptides, as well as their advantages and limitations, and explores the application of AI in antimicrobial peptides prediction amd design. This highlights the crucial role of AI in enhancing the efficiency of antimicrobial peptide research and provides a reference for antimicrobial drug development.
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Affiliation(s)
- Shuaiqi Ji
- College of Food Science, Shenyang Agricultural University, Shenyang, 110866, PR China; Shenyang Key Laboratory of Microbial Fermentation Technology Innovation, Shenyang, 110866, PR China
| | - Feiyu An
- College of Food Science, Shenyang Agricultural University, Shenyang, 110866, PR China; Liaoning Engineering Research Center of Food Fermentation Technology, Shenyang, 110866, PR China
| | - Taowei Zhang
- College of Food Science, Shenyang Agricultural University, Shenyang, 110866, PR China; Shenyang Key Laboratory of Microbial Fermentation Technology Innovation, Shenyang, 110866, PR China
| | - Mengxue Lou
- College of Food Science, Shenyang Agricultural University, Shenyang, 110866, PR China; Liaoning Engineering Research Center of Food Fermentation Technology, Shenyang, 110866, PR China
| | - Jiawei Guo
- College of Food Science, Shenyang Agricultural University, Shenyang, 110866, PR China; Shenyang Key Laboratory of Microbial Fermentation Technology Innovation, Shenyang, 110866, PR China
| | - Kexin Liu
- College of Food Science, Shenyang Agricultural University, Shenyang, 110866, PR China; Shenyang Key Laboratory of Microbial Fermentation Technology Innovation, Shenyang, 110866, PR China
| | - Yi Zhu
- College of Food Science, Shenyang Agricultural University, Shenyang, 110866, PR China; Liaoning Engineering Research Center of Food Fermentation Technology, Shenyang, 110866, PR China
| | - Junrui Wu
- College of Food Science, Shenyang Agricultural University, Shenyang, 110866, PR China; Liaoning Engineering Research Center of Food Fermentation Technology, Shenyang, 110866, PR China; Shenyang Key Laboratory of Microbial Fermentation Technology Innovation, Shenyang, 110866, PR China.
| | - Rina Wu
- College of Food Science, Shenyang Agricultural University, Shenyang, 110866, PR China; Liaoning Engineering Research Center of Food Fermentation Technology, Shenyang, 110866, PR China; Shenyang Key Laboratory of Microbial Fermentation Technology Innovation, Shenyang, 110866, PR China.
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9
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Scoffone VC, Barbieri G, Irudal S, Trespidi G, Buroni S. New Antimicrobial Strategies to Treat Multi-Drug Resistant Infections Caused by Gram-Negatives in Cystic Fibrosis. Antibiotics (Basel) 2024; 13:71. [PMID: 38247630 PMCID: PMC10812592 DOI: 10.3390/antibiotics13010071] [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: 12/20/2023] [Revised: 01/05/2024] [Accepted: 01/09/2024] [Indexed: 01/23/2024] Open
Abstract
People with cystic fibrosis (CF) suffer from recurrent bacterial infections which induce inflammation, lung tissue damage and failure of the respiratory system. Prolonged exposure to combinatorial antibiotic therapies triggers the appearance of multi-drug resistant (MDR) bacteria. The development of alternative antimicrobial strategies may provide a way to mitigate antimicrobial resistance. Here we discuss different alternative approaches to the use of classic antibiotics: anti-virulence and anti-biofilm compounds which exert a low selective pressure; phage therapies that represent an alternative strategy with a high therapeutic potential; new methods helping antibiotics activity such as adjuvants; and antimicrobial peptides and nanoparticle formulations. Their mechanisms and in vitro and in vivo efficacy are described, in order to figure out a complete landscape of new alternative approaches to fight MDR Gram-negative CF pathogens.
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Affiliation(s)
| | | | | | | | - Silvia Buroni
- Department of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, 27100 Pavia, Italy; (V.C.S.); (G.B.); (S.I.); (G.T.)
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10
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Liu F, Greenwood AI, Xiong Y, Miceli RT, Fu R, Anderson KW, McCallum SA, Mihailescu M, Gross R, Cotten ML. Host Defense Peptide Piscidin and Yeast-Derived Glycolipid Exhibit Synergistic Antimicrobial Action through Concerted Interactions with Membranes. JACS AU 2023; 3:3345-3365. [PMID: 38155643 PMCID: PMC10751773 DOI: 10.1021/jacsau.3c00506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 09/25/2023] [Accepted: 09/29/2023] [Indexed: 12/30/2023]
Abstract
Developing new antimicrobials as alternatives to conventional antibiotics has become an urgent race to eradicate drug-resistant bacteria and to save human lives. Conventionally, antimicrobial molecules are studied independently even though they can be cosecreted in vivo. In this research, we investigate two classes of naturally derived antimicrobials: sophorolipid (SL) esters as modified yeast-derived glycolipid biosurfactants that feature high biocompatibility and low production cost; piscidins, which are host defense peptides (HDPs) from fish. While HDPs such as piscidins target the membrane of pathogens, and thus result in low incidence of resistance, SLs are not well understood on a mechanistic level. Here, we demonstrate that combining SL-hexyl ester (SL-HE) with subinhibitory concentration of piscidins 1 (P1) and 3 (P3) stimulates strong antimicrobial synergy, potentiating a promising therapeutic window. Permeabilization assays and biophysical studies employing circular dichroism, NMR, mass spectrometry, and X-ray diffraction are performed to investigate the mechanism underlying this powerful synergy. We reveal four key mechanistic features underlying the synergistic action: (1) P1/3 binds to SL-HE aggregates, becoming α-helical; (2) piscidin-glycolipid assemblies synergistically accumulate on membranes; (3) SL-HE used alone or bound to P1/3 associates with phospholipid bilayers where it induces defects; (4) piscidin-glycolipid complexes disrupt the bilayer structure more dramatically and differently than either compound alone, with phase separation occurring when both agents are present. Overall, dramatic enhancement in antimicrobial activity is associated with the use of two membrane-active agents, with the glycolipid playing the roles of prefolding the peptide, coordinating the delivery of both agents to bacterial surfaces, recruiting the peptide to the pathogenic membranes, and supporting membrane disruption by the peptide. Given that SLs are ubiquitously and safely used in consumer products, the SL/peptide formulation engineered and mechanistically characterized in this study could represent fertile ground to develop novel synergistic agents against drug-resistant bacteria.
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Affiliation(s)
- Fei Liu
- Department
of Chemistry, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Alexander I. Greenwood
- Department
of Applied Science, William & Mary, Williamsburg, Virginia 23185, United States
| | - Yawei Xiong
- Department
of Applied Science, William & Mary, Williamsburg, Virginia 23185, United States
| | - Rebecca T. Miceli
- Department
of Chemistry, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
- Center
for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Riqiang Fu
- Center
of Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - Kyle W. Anderson
- National
Institute of Standards and Technology, Rockville, Maryland 20850, United States
| | - Scott A. McCallum
- Center
for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Mihaela Mihailescu
- Institute
for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland 20850, United States
| | - Richard Gross
- Department
of Chemistry, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
- Center
for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Myriam L. Cotten
- Department
of Applied Science, William & Mary, Williamsburg, Virginia 23185, United States
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11
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Zhong X, Deng K, Yang X, Song X, Zou Y, Zhou X, Tang H, Li L, Fu Y, Yin Z, Wan H, Zhao X. Brevicidine acts as an effective sensitizer of outer membrane-impermeable conventional antibiotics for Acinetobacter baumannii treatment. Front Microbiol 2023; 14:1304198. [PMID: 38173680 PMCID: PMC10762313 DOI: 10.3389/fmicb.2023.1304198] [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: 09/29/2023] [Accepted: 11/27/2023] [Indexed: 01/05/2024] Open
Abstract
The antibiotic resistance of Acinetobacter baumannii poses a significant threat to global public health, especially those strains that are resistant to carbapenems. Therefore, novel strategies are desperately needed for the treatment of infections caused by antibiotic-resistant A. baumannii. In this study, we report that brevicidine, a bacterial non-ribosomally produced cyclic lipopeptide, shows synergistic effects with multiple outer membrane-impermeable conventional antibiotics against A. baumannii. In particular, brevicidine, at a concentration of 1 μM, lowered the minimum inhibitory concentration of erythromycin, azithromycin, and rifampicin against A. baumannii strains by 32-128-fold. Furthermore, mechanistic studies were performed by employing erythromycin as an example of an outer membrane-impermeable conventional antibiotic, which showed the best synergistic effects with brevicidine against the tested A. baumannii strains in the present study. The results demonstrate that brevicidine disrupted the outer membrane of A. baumannii at a concentration range of 0.125-4 μM in a dose-dependent manner. This capacity of brevicidine could help the tested outer membrane-impermeable antibiotics enter A. baumannii cells and thereafter exert their antimicrobial activity. In addition, the results show that brevicidine-erythromycin combination exerted strong A. baumannii killing capacity by the enhanced inhibition of adenosine triphosphate biosynthesis and accumulation of reactive oxygen species, which are the main mechanisms causing the death of bacteria. Interestingly, brevicidine and erythromycin combination showed good therapeutic effects on A. baumannii-induced mouse peritonitis-sepsis models. These findings demonstrate that brevicidine is a promising sensitizer candidate of outer membrane-impermeable conventional antibiotics for treating A. baumannii infections in the post-antibiotic age.
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Affiliation(s)
- Xinyi Zhong
- Center for Sustainable Antimicrobials, Department of Pharmacy, Sichuan Agricultural University, Chengdu, China
- Center for Infectious Diseases Control (CIDC), Sichuan Agricultural University, Chengdu, China
| | - Kai Deng
- Center for Infectious Diseases Control (CIDC), Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China
| | - Xiuhan Yang
- Center for Sustainable Antimicrobials, Department of Pharmacy, Sichuan Agricultural University, Chengdu, China
- Center for Infectious Diseases Control (CIDC), Sichuan Agricultural University, Chengdu, China
| | - Xu Song
- Center for Sustainable Antimicrobials, Department of Pharmacy, Sichuan Agricultural University, Chengdu, China
- Center for Infectious Diseases Control (CIDC), Sichuan Agricultural University, Chengdu, China
| | - Yuanfeng Zou
- Center for Sustainable Antimicrobials, Department of Pharmacy, Sichuan Agricultural University, Chengdu, China
- Center for Infectious Diseases Control (CIDC), Sichuan Agricultural University, Chengdu, China
| | - Xun Zhou
- Center for Sustainable Antimicrobials, Department of Pharmacy, Sichuan Agricultural University, Chengdu, China
- Center for Infectious Diseases Control (CIDC), Sichuan Agricultural University, Chengdu, China
| | - Huaqiao Tang
- Center for Sustainable Antimicrobials, Department of Pharmacy, Sichuan Agricultural University, Chengdu, China
- Center for Infectious Diseases Control (CIDC), Sichuan Agricultural University, Chengdu, China
| | - Lixia Li
- Center for Sustainable Antimicrobials, Department of Pharmacy, Sichuan Agricultural University, Chengdu, China
- Center for Infectious Diseases Control (CIDC), Sichuan Agricultural University, Chengdu, China
| | - Yuping Fu
- Center for Sustainable Antimicrobials, Department of Pharmacy, Sichuan Agricultural University, Chengdu, China
- Center for Infectious Diseases Control (CIDC), Sichuan Agricultural University, Chengdu, China
| | - Zhongqiong Yin
- Center for Sustainable Antimicrobials, Department of Pharmacy, Sichuan Agricultural University, Chengdu, China
- Center for Infectious Diseases Control (CIDC), Sichuan Agricultural University, Chengdu, China
| | - Hongping Wan
- Center for Infectious Diseases Control (CIDC), Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China
| | - Xinghong Zhao
- Center for Sustainable Antimicrobials, Department of Pharmacy, Sichuan Agricultural University, Chengdu, China
- Center for Infectious Diseases Control (CIDC), Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China
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12
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Cebrián R, Lucas R, Fernández-Cantos MV, Slot K, Peñalver P, Martínez-García M, Párraga-Leo A, de Paz MV, García F, Kuipers OP, Morales JC. Synthesis and antimicrobial activity of aminoalkyl resveratrol derivatives inspired by cationic peptides. J Enzyme Inhib Med Chem 2023; 38:267-281. [PMID: 36600674 PMCID: PMC9828810 DOI: 10.1080/14756366.2022.2146685] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Antimicrobial resistance is a global concern, far from being resolved. The need of new drugs against new targets is imminent. In this work, we present a family of aminoalkyl resveratrol derivatives with antibacterial activity inspired by the properties of cationic amphipathic antimicrobial peptides. Surprisingly, the newly designed molecules display modest activity against aerobically growing bacteria but show surprisingly good antimicrobial activity against anaerobic bacteria (Gram-negative and Gram-positive) suggesting specificity towards this bacterial group. Preliminary studies into the action mechanism suggest that activity takes place at the membrane level, while no cross-resistance with traditional antibiotics is observed. Actually, some good synergistic relations with existing antibiotics were found against Gram-negative pathogens. However, some cytotoxicity was observed, despite their low haemolytic activity. Our results show the importance of the balance between positively charged moieties and hydrophobicity to improve antimicrobial activity, setting the stage for the design of new drugs based on these molecules.
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Affiliation(s)
- Rubén Cebrián
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands,Department of Clinical Microbiology, Instituto de Investigación Biosanitaria ibs. GRANADA, University Hospital Clínico San Cecilio, Granada, Spain,CONTACT Rubén Cebrián University Hospital San Cecilio,Clinical Microbiology Department, Av. de la Innovación s/n, 18061, Granada, Spain
| | - Ricardo Lucas
- Department of Organic and Pharmaceutical Chemistry, School of Pharmacy, University of Seville, Seville, Spain
| | - María Victoria Fernández-Cantos
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Koen Slot
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Pablo Peñalver
- Department of Biochemistry and Molecular Pharmacology, Instituto de Parasitología y Biomedicina López Neyra, CSIC, PTS Granada, Armilla, Granada, Spain
| | - Marta Martínez-García
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Antonio Párraga-Leo
- Department of Organic and Pharmaceutical Chemistry, School of Pharmacy, University of Seville, Seville, Spain
| | - María Violante de Paz
- Department of Organic and Pharmaceutical Chemistry, School of Pharmacy, University of Seville, Seville, Spain
| | - Federico García
- Department of Clinical Microbiology, Instituto de Investigación Biosanitaria ibs. GRANADA, University Hospital Clínico San Cecilio, Granada, Spain
| | - Oscar P. Kuipers
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands,Oscar P. Kuipers University of Groningen, Faculty of Science and Engineering, Department of Genetics, Nijenborgh 7, 9747AG, Groningen, The Netherlands
| | - Juan Carlos Morales
- Department of Biochemistry and Molecular Pharmacology, Instituto de Parasitología y Biomedicina López Neyra, CSIC, PTS Granada, Armilla, Granada, Spain,Juan Carlos Morales Instituto de Parasitología y Biomedicina López Neyra, CSIC, PTS Granada, Avda. del Conocimiento 17, Armilla, 18016Granada, Spain
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13
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Han R, Xing J, Sun H, Guo Z, Yi K, Hu G, Zhai Y, Velkov T, Wu H. The antihelminth drug rafoxanide reverses chromosomal-mediated colistin-resistance in Klebsiella pneumoniae. mSphere 2023; 8:e0023423. [PMID: 37747188 PMCID: PMC10597454 DOI: 10.1128/msphere.00234-23] [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: 04/26/2023] [Accepted: 08/03/2023] [Indexed: 09/26/2023] Open
Abstract
The emergence and rapid spread of multi-drug-resistant (MDR) bacteria pose a serious threat to global healthcare. Although the synergistic effect of rafoxanide and colistin was reported, little is known regarding the potential mechanism of this synergy, particularly against chromosomal-mediated colistin-resistant Klebsiella pneumoniae. In the present study, we elucidated the synergistic effect of rafoxanide and colistin against chromosomal-mediated colistin-resistant Klebsiella pneumoniae isolates from human (KP-9) and swine (KP-1) infections. Treatment with 1 mg/L rafoxanide overtly reversed the MIC max to 512-fold. Time-kill assays indicated that rafoxanide acted synergistically with colistin against the growth of KP-1 and KP-9. Mechanistically, we unexpectedly found that the combination destroys the inner-membrane integrity, and ATP synthesis was also quenched, albeit, not via F1F0-ATPase; thereby also inhibiting the activity of efflux pumps. Excessive production of reactive oxygen species (ROS) was also an underlying factor contributing to the bacterial-killing effect of the combination. Transcriptomic analysis unraveled overt heterogeneous expression as treated with both administrations compared with monotherapy. Functional analysis of these differentially expressed genes (DEGs) targeted to the plasma membrane and ATP-binding corroborated phenotypic screening results. These novel findings highlight the synergistic mechanism of rafoxanide in combination with colistin which effectively eradicates chromosomal-mediated colistin-resistant Klebsiella pneumoniae. IMPORTANCE The antimicrobial resistance of Klebsiella pneumoniae caused by the abuse of colistin has increased the difficulty of clinical treatment. A promising combination (i.e., rafoxanide+ colistin) has successfully rescued the antibacterial effect of colistin. However, we still failed to know the potential effect of this combination on chromosome-mediated Klebsiella pneumoniae. Through a series of in vitro experiments, as well as transcriptomic profiling, we confirmed that the MIC of colistin was reduced by rafoxanide by destroying the inner-membrane integrity, quenching ATP synthesis, inhibiting the activity of the efflux pump, and increasing the production of reactive oxygen species. In turn, the expression of relevant colistin resistance genes was down-regulated. Collectively, our study revealed rafoxanide as a promising colistin adjuvant against chromosome-mediated Klebsiella pneumoniae.
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Affiliation(s)
- Rongjia Han
- Department of Pharmacology and Toxicology, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China
| | - Jiabao Xing
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Huarun Sun
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, China
| | - Zeyu Guo
- National Reference Laboratory of Veterinary Drug Residues (SCAU), College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Kaifang Yi
- Department of Pharmacology and Toxicology, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China
| | - Gongzheng Hu
- Department of Pharmacology and Toxicology, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China
| | - Yajun Zhai
- Department of Pharmacology and Toxicology, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China
| | - Tony Velkov
- Department of Pharmacology, Biodiscovery Institute, Monash University, Clayton, Victoria, Australia
| | - Hua Wu
- Department of Pharmacology and Toxicology, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China
- Department of Pharmacology, Biodiscovery Institute, Monash University, Clayton, Victoria, Australia
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14
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Tang M, Zhao D, Liu S, Zhang X, Yao Z, Chen H, Zhou C, Zhou T, Xu C. The Properties of Linezolid, Rifampicin, and Vancomycin, as Well as the Mechanism of Action of Pentamidine, Determine Their Synergy against Gram-Negative Bacteria. Int J Mol Sci 2023; 24:13812. [PMID: 37762115 PMCID: PMC10530309 DOI: 10.3390/ijms241813812] [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: 08/01/2023] [Revised: 09/02/2023] [Accepted: 09/05/2023] [Indexed: 09/29/2023] Open
Abstract
Combining pentamidine with Gram-positive-targeting antibiotics has been proven to be a promising strategy for treating infections from Gram-negative bacteria (GNB). However, which antibiotics pentamidine can and cannot synergize with and the reasons for the differences are unclear. This study aimed to identify the possible mechanisms for the differences in the synergy of pentamidine with rifampicin, linezolid, tetracycline, erythromycin, and vancomycin against GNB. Checkerboard assays were used to detect the synergy of pentamidine and the different antibiotics. To determine the mechanism of pentamidine, fluorescent labeling assays were used to measure membrane permeability, membrane potential, efflux pump activity, and reactive oxygen species (ROS); the LPS neutralization assay was used to evaluate the target site; and quantitative PCR was used to measure changes in efflux pump gene expression. Our results revealed that pentamidine strongly synergized with rifampicin, linezolid, and tetracycline and moderately synergized with erythromycin, but did not synergize with vancomycin against E. coli, K. pneumoniae, E. cloacae, and A. baumannii. Pentamidine increased the outer membrane permeability but did not demolish the outer and inner membranes, which exclusively permits the passage of hydrophobic, small-molecule antibiotics while hindering the entry of hydrophilic, large-molecule vancomycin. It dissipated the membrane proton motive force and inactivated the efflux pump, allowing the intracellular accumulation of antimicrobials that function as substrates of the efflux pump, such as linezolid. These processes resulted in metabolic perturbation and ROS production which ultimately was able to destroy the bacteria. These mechanisms of action of pentamidine on GNB indicate that it is prone to potentiating hydrophobic, small-molecule antibiotics, such as rifampicin, linezolid, and tetracycline, but not hydrophilic, large-molecule antibiotics like vancomycin against GNB. Collectively, our results highlight the importance of the physicochemical properties of antibiotics and the specific mechanisms of action of pentamidine for the synergy of pentamidine-antibiotic combinations. Pentamidine engages in various pathways in its interactions with GNB, but these mechanisms determine its specific synergistic effects with certain antibiotics against GNB. Pentamidine is a promising adjuvant, and we can optimize drug compatibility by considering its functional mechanisms.
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Affiliation(s)
- Miran Tang
- Department of Clinical Laboratory, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325035, China; (M.T.); (S.L.); (X.Z.); (Z.Y.); (H.C.); (C.Z.)
| | - Deyi Zhao
- Department of Medical Lab Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou 325015, China;
| | - Sichen Liu
- Department of Clinical Laboratory, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325035, China; (M.T.); (S.L.); (X.Z.); (Z.Y.); (H.C.); (C.Z.)
| | - Xiaotuan Zhang
- Department of Clinical Laboratory, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325035, China; (M.T.); (S.L.); (X.Z.); (Z.Y.); (H.C.); (C.Z.)
| | - Zhuocheng Yao
- Department of Clinical Laboratory, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325035, China; (M.T.); (S.L.); (X.Z.); (Z.Y.); (H.C.); (C.Z.)
| | - Hule Chen
- Department of Clinical Laboratory, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325035, China; (M.T.); (S.L.); (X.Z.); (Z.Y.); (H.C.); (C.Z.)
| | - Cui Zhou
- Department of Clinical Laboratory, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325035, China; (M.T.); (S.L.); (X.Z.); (Z.Y.); (H.C.); (C.Z.)
| | - Tieli Zhou
- Department of Clinical Laboratory, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325035, China; (M.T.); (S.L.); (X.Z.); (Z.Y.); (H.C.); (C.Z.)
| | - Chunquan Xu
- Department of Clinical Laboratory, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325035, China; (M.T.); (S.L.); (X.Z.); (Z.Y.); (H.C.); (C.Z.)
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15
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Yang L, Tian Z, Zhao W, Zhang J, Tian C, Zhou L, Jiao Z, Peng J, Guo G. Novel antimicrobial peptide DvAMP serves as a promising antifungal agent against Cryptococcus neoformans. Bioorg Chem 2023; 138:106679. [PMID: 37329812 DOI: 10.1016/j.bioorg.2023.106679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 05/30/2023] [Accepted: 06/12/2023] [Indexed: 06/19/2023]
Abstract
Cryptococcus neoformans is an important opportunistic human fungal pathogen that causes cryptococcosis in immunocompromised patients. However, the number of drugs for the treatment of cryptococcosis is restricted, and the development of novel antifungal drugs and innovative strategies for the treatment of cryptococcosis is urgently needed. In this study, we validated that DvAMP is a novel antimicrobial peptide with antimicrobial activity and that it was obtained by pre-screening from the UniProt database of more than three million unknown functional sequences based on the quantitative structure-activity relationships (QSARs) protocol (http://www.chemoinfolab.com/antifungal). The peptide exhibited satisfactory biosafety and physicochemical properties, and relatively rapid fungicidal activity against C. neoformans. Meanwhile, DvAMP was able to inhibit the static biofilm of C. neoformans and cause a reduction in the thickness of the capsule. In addition, DvAMP exerts antifungal effects through membrane-mediated mechanisms (membrane permeability and depolarization) and mitochondrial dysfunction, involving a hybrid multi-hit mechanism. Furthermore, by using the C. neoformans-Galleria mellonella infection model, we demonstrated that DvAMP has significant therapeutic effects in vivo and that it significantly reduces the mortality and fungal burden of infected larvae. These results suggest that DvAMP may be a potential antifungal drug candidate for the treatment of cryptococcosis.
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Affiliation(s)
- Longbing Yang
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang 550025, China; Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China; Translational Medicine Research Center, Guizhou Medical University, Guiyang 550025, China
| | - Zhuqing Tian
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang 550025, China
| | - Wenjing Zhao
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang 550025, China
| | - Jin Zhang
- School of Public Health, Guizhou Medical University, Guiyang 550025, China
| | - Chunren Tian
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang 550025, China
| | - Luoxiong Zhou
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang 550025, China; School of Public Health, Guizhou Medical University, Guiyang 550025, China
| | - Zhenlong Jiao
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang 550025, China; Translational Medicine Research Center, Guizhou Medical University, Guiyang 550025, China
| | - Jian Peng
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang 550025, China; Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China
| | - Guo Guo
- The Key and Characteristic Laboratory of Modern Pathogen Biology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang 550025, China; Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang 550025, China; Translational Medicine Research Center, Guizhou Medical University, Guiyang 550025, China.
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16
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Tang M, Qian C, Zhang X, Liu Y, Pan W, Yao Z, Zeng W, Xu C, Zhou T. When Combined with Pentamidine, Originally Ineffective Linezolid Becomes Active in Carbapenem-Resistant Enterobacteriaceae. Microbiol Spectr 2023; 11:e0313822. [PMID: 37125928 PMCID: PMC10269503 DOI: 10.1128/spectrum.03138-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 04/11/2023] [Indexed: 05/02/2023] Open
Abstract
The increasing prevalence of carbapenem-resistant Enterobacteriaceae (CRE) and their biofilm-relevant infections pose a threat to public health. The drug combination strategy provides a new treatment option for CRE infections. This study explored the synergistic antibacterial, antibiofilm activities as well as the in vivo efficacy against CRE of pentamidine combined with linezolid. This study further revealed the possible mechanisms underlying the synergy of the combination. The checkerboard and time-kill assays showed that pentamidine combined with linezolid had significant synergistic antibacterial effects against CRE strains (9/10). Toxicity assays on mammal cells (mouse RAW264.7 and red blood cells) and on Galleria mellonella confirmed that the concentrations of pentamidine and/or linezolid that were used were relatively safe. Antibiofilm activity detection via crystal violet staining, viable bacteria counts, and scanning electron microscopy demonstrated that the combination enhanced the inhibition of biofilm formation and the elimination of established biofilms. The G. mellonella infection model and mouse thigh infection model demonstrated the potential in vivo efficacy of the combination. In particular, a series of mechanistic experiments elucidated the possible mechanisms for the synergy in which pentamidine disrupts the outer membranes, dissipates the membrane potentials, and devitalizes the efflux pumps of CRE, thereby facilitating the intracellular accumulation of linezolid and reactive oxygen species (ROS), which ultimately kills the bacteria. Taken together, when combined with pentamidine, which acts as an outer membrane permeabilizer and as an efflux pump inhibitor, originally ineffective linezolid becomes active in CRE and exhibits excellent synergistic antibacterial and antibiofilm effects as well as a potential therapeutic effect in vivo on CRE-relevant infections. IMPORTANCE The multidrug resistance and biofilm formation of Gram-negative bacteria (GNB) may lead to incurable "superbug" infections. Drug combinations, with the potential to augment the original treatment ranges of drugs, are alternative treatment strategies against GNB. In this study, the pentamidine-linezolid combination showed notable antibacterial and antibiofilm activity both in vitro and in vivo against the problem carbapenem-resistant Enterobacteriaceae (CRE). Pentamidine is often used as an antiprotozoal and antifungal agent, and linezolid is a defensive Gram-positive bacteria (GPB) antimicrobial. Their combination expands the treatment range to GNB. Hence, the pentamidine-linezolid pair may be an effective treatment for complex infections that are mixed by GPB, GNB, and even fungi. In terms of mechanism, pentamidine inhibited the outer membranes, membrane potentials, and efflux pumps of CRE. This might be a universal mechanism by which pentamidine, as an adjuvant, potentiates other drugs, similar to linezolid, thereby having synergistic antibacterial effects on CRE.
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Affiliation(s)
- Miran Tang
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, China
| | - Changrui Qian
- School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang Province, China
| | - Xiaotuan Zhang
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, China
| | - Yan Liu
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, China
| | - Wei Pan
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, China
| | - Zhuocheng Yao
- Department of Medical Lab Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang Province, China
| | - Weiliang Zeng
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, China
| | - Chunquan Xu
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, China
| | - Tieli Zhou
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, China
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17
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Bagewadi ZK, Aakanksha UK, Yaraguppi DA, Yunus Khan TM, Deshpande SH, Dammalli M, Revankar AG, Savalagi AJ, Hiremath SV. Molecular docking and simulation studies against nucleoside diphosphate kinase (NDK) of Pseudomonas aeruginosa with secondary metabolite identified by genome mining from paenibacillusehimensis. J Biomol Struct Dyn 2023; 41:12610-12619. [PMID: 36651083 DOI: 10.1080/07391102.2023.2167118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 01/05/2023] [Indexed: 01/19/2023]
Abstract
Pseudomonas aeruginosa is one of the leading opportunistic pathogens that causes nosocomial pneumonia and mostly in people with cystic fibrosis. In the present study, an in-silicoapproach was adopted to identify the novel drug target against Pseudomonas aeruginosa by employing subtractive genomics and molecular docking studies. Each step in the subtractive genomics scrutinized the bacterial proteome and determined a potential drug target against Pseudomonas aeruginosa. 71 essential proteins were obtained from the subcellular localization method that resides in the extracellular region. Metabolic pathways were studied to elucidate the unique pathways where the involvement of proteins present in the pathogen was predicted and a total of 6 unique pathways were determined. By, Genome mining of the source organism Paenibacillusehimensis, 9 ligands were obtained. The molecular docking analysis between the binding site of target protein NDK and ligands was carried out by employing the AutoDock Vina tool. Based on the highest binding affinity, Paenibactin, AnabaenopeptinNZ857 and Nostamide A complex with NDK protein with a lower binding energy of -7.5 kcal/mol, -7.4and -7.2 kcal/molrespectively were considered for the simulation studies. Molecular dynamics simulation studies showed the ligand in complex with protein was highly stable and rigid for a duration of 150 ns. For Paenibactin, AnabaenopeptinNZ857 and Nostamide Acomplex with protein, RMSD plot showed a deviation of ∼0.2-0.3 nm till ∼30ns/50 ns-110ns and further stabilized. The radius of the gyration plot clearly showed that the values stayed at ∼1.45 nm- 1.55 nm showing compactness and stability. The SASA stayed at the range ∼80nm2 and at least one total number of hydrogen bonds was shown throughout the 150 ns simulation for all three possible ligand-protein complexes. In the RMSF plot, the maximum fluctuation was ranged from ∼0.4-0.42 nm at the range between ∼57ns-60ns.The Paenibactin, AnabaenopeptinNZ857 and Nostamide A complex with NDK protein showed a stable, rigid and compact interaction throughout the simulation of duration 150 ns.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Zabin K Bagewadi
- Department of Biotechnology, KLE Technological University, Hubballi, India
| | - U K Aakanksha
- Department of Biotechnology, KLE Technological University, Hubballi, India
| | - Deepak A Yaraguppi
- Department of Biotechnology, KLE Technological University, Hubballi, India
| | - T M Yunus Khan
- Department of Mechanical Engineering, College of Engineering, King Khalid University, Abha, Kingdom of Saudi Arabia
| | - Sanjay H Deshpande
- Department of Biotechnology, KLE Technological University, Hubballi, India
| | - Manjunath Dammalli
- Department of Biotechnology, Siddaganga Institute of Technology, Tumkur, India
| | - Archana G Revankar
- Department of Biotechnology, KLE Technological University, Hubballi, India
| | - Anudeep J Savalagi
- Department of Biotechnology, KLE Technological University, Hubballi, India
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Pseudomonas aeruginosa Phosphate Transporter PitA (PA4292) Controls Susceptibility to Aminoglycoside Antibiotics by Regulating the Proton Motive Force. Antimicrob Agents Chemother 2022; 66:e0099222. [PMID: 36346250 PMCID: PMC9765264 DOI: 10.1128/aac.00992-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Pseudomonas aeruginosa is an opportunistic Gram-negative bacterium that causes nosocomial infections in immunocompromised patients. β-lactam and aminoglycoside antibiotics are commonly used in the treatment of P. aeruginosa infections. Previously, we found that mutation in a PA4292 gene increases bacterial resistance to β-lactam antibiotics. In this study, we demonstrated that mutation in PA4292 increases bacterial susceptibility to aminoglycoside antibiotics. We further found enhanced uptake of tobramycin by the ΔPA4292 mutant, which might be due to an increase of proton motive force (PMF). Sequence analysis revealed PA4292 is homologous to the Escherichia coli phosphate transporter PitA. Mutation of PA4292 indeed reduces intracellular phosphate concentration. We thus named PA4292 as pitA. Although the PMF is enhanced in the ΔpitA mutant, the intracellular ATP concentration is lower than that in the isogenic wild-type strain PA14, which might be due to lack of the ATP synthesis substrate phosphate. Overexpression of the phosphate transporter complex genes pstSCAB in the ΔpitA mutant restores the intracellular phosphate concentration, PMF, ATP synthesis, and aminoglycosides resistance. In addition, growth of wild-type PA14 in a low-phosphate medium resulted in higher PMF and aminoglycoside susceptibility compared to cells grown in a high-phosphate medium. Overall, our results demonstrate the roles of PitA in phosphate transportation and reveal the relationship between intracellular phosphate and aminoglycoside susceptibility.
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Development of Resistance to Eravacycline by Klebsiella pneumoniae and Collateral Sensitivity-Guided Design of Combination Therapies. Microbiol Spectr 2022; 10:e0139022. [PMID: 35972286 PMCID: PMC9603973 DOI: 10.1128/spectrum.01390-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The evolution of bacterial antibiotic resistance is exhausting the list of currently used antibiotics and endangers those in the pipeline. The combination of antibiotics is a promising strategy that may suppress resistance development and/or achieve synergistic therapeutic effects. Eravacycline is a newly approved antibiotic that is effective against a variety of multidrug-resistant (MDR) pathogens. However, the evolution of resistance to eravacycline and strategies to suppress the evolution remain unexplored. Here, we demonstrated that a carbapenem-resistant Klebsiella pneumoniae clinical isolate quickly developed resistance to eravacycline, which is mainly caused by mutations in the gene encoding the Lon protease. The evolved resistant mutants display collateral sensitivities to β-lactam/β-lactamase inhibitor (BLBLI) combinations aztreonam/avibactam and ceftazidime-avibactam. Proteomic analysis revealed upregulation of the multidrug efflux system AcrA-AcrB-TolC and porin proteins OmpA and OmpU, which contributed to the increased resistance to eravacycline and susceptibility to BLBLIs, respectively. The combination of eravacycline with aztreonam/avibactam or ceftazidime-avibactam suppresses resistance development. We further demonstrated that eravacycline-resistant mutants evolved from an NDM-1-containing K. pneumoniae strain display collateral sensitivity to aztreonam/avibactam, and the combination of eravacycline with aztreonam/avibactam suppresses resistance development. In addition, the combination of eravacycline with aztreonam/avibactam or ceftazidime-avibactam displayed synergistic therapeutic effects in a murine cutaneous abscess model. Overall, our results revealed mechanisms of resistance to eravacycline and collateral sensitivities to BLBLIs and provided promising antibiotic combinations in the treatment of multidrug-resistant K. pneumoniae infections. IMPORTANCE The increasing bacterial antibiotic resistance is a serious threat to global public health, which demands novel antimicrobial medicines and treatment strategies. Eravacycline is a newly approved antibiotic that belongs to the tetracycline antibiotics. Here, we found that a multidrug-resistant Klebsiella pneumoniae clinical isolate rapidly developed resistance to eravacycline and the evolved resistant mutants displayed collateral sensitivity to antibiotics aztreonam/avibactam and ceftazidime-avibactam. We demonstrated that the combination of eravacycline with aztreonam/avibactam or ceftazidime-avibactam repressed resistance development and improved the treatment efficacies. We also elucidated the mechanisms that contribute to the increased resistance to eravacycline and susceptibility to aztreonam/avibactam and ceftazidime-avibactam. This work demonstrated the mechanisms of antibiotic resistance and collateral sensitivity and provided a new therapeutically option for effective antibiotic combinations.
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Truncated Pleurocidin Derivative with High Pepsin Hydrolysis Resistance to Combat Multidrug-Resistant Pathogens. Pharmaceutics 2022; 14:pharmaceutics14102025. [PMID: 36297458 PMCID: PMC9610943 DOI: 10.3390/pharmaceutics14102025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 09/13/2022] [Accepted: 09/20/2022] [Indexed: 11/29/2022] Open
Abstract
The global prevalence of antimicrobial resistance calls for the development of novel antimicrobial agents, particularly for these orally available drugs. Structural modifications of the natural antimicrobial peptides (AMPs) provide a straightforward approach to develop potent antimicrobial agents with high specificity and low toxicity. In this study, we truncated 11-amino-acids at the C-terminus of Pleurocidin, an AMP produced by Pleuronectes americanus, and obtained four peptide analogues termed GK-1, GK-2, GK-3 and GK-4. Minimum inhibitory concentration (MIC) tests showed that GK-1 obtained by direct truncation of Pleurocidin has no antibacterial activity, while GK-2, GK-3 and GK-4 show considerable antibacterial activity with Pleurocidin. Notably, GK-4 displays rapid bacteriostatic activity, great stability and low hemolysis, as well as enhanced hydrolytic resistance to pepsin treatment. Mechanistic studies showed that GK-4 induces membrane damage by interacting with bacterial membrane-specific components, dissipates bacterial membrane potential and promotes the generation of ROS. SEM and CD analysis further confirmed the ability of GK-4 to resist pepsin hydrolysis, which may be attributed to its stable helicity structure. Collectively, our findings reveal that GK-4 is a potential orally available candidate to treat infections caused by multidrug-resistant pathogens.
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Wesseling CJ, Martin NI. Synergy by Perturbing the Gram-Negative Outer Membrane: Opening the Door for Gram-Positive Specific Antibiotics. ACS Infect Dis 2022; 8:1731-1757. [PMID: 35946799 PMCID: PMC9469101 DOI: 10.1021/acsinfecdis.2c00193] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
New approaches to target antibacterial agents toward Gram-negative bacteria are key, given the rise of antibiotic resistance. Since the discovery of polymyxin B nonapeptide as a potent Gram-negative outer membrane (OM)-permeabilizing synergist in the early 1980s, a vast amount of literature on such synergists has been published. This Review addresses a range of peptide-based and small organic compounds that disrupt the OM to elicit a synergistic effect with antibiotics that are otherwise inactive toward Gram-negative bacteria, with synergy defined as a fractional inhibitory concentration index (FICI) of <0.5. Another requirement for the inclusion of the synergists here covered is their potentiation of a specific set of clinically used antibiotics: erythromycin, rifampicin, novobiocin, or vancomycin. In addition, we have focused on those synergists with reported activity against Gram-negative members of the ESKAPE family of pathogens namely, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and/or Acinetobacter baumannii. In cases where the FICI values were not directly reported in the primary literature but could be calculated from the published data, we have done so, allowing for more direct comparison of potency with other synergists. We also address the hemolytic activity of the various OM-disrupting synergists reported in the literature, an effect that is often downplayed but is of key importance in assessing the selectivity of such compounds for Gram-negative bacteria.
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