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Yoon J, Jo Y, Shin S. Understanding Antimicrobial Peptide Synergy: Differential Binding Interactions and Their Impact on Membrane Integrity. J Phys Chem B 2024. [PMID: 39347577 DOI: 10.1021/acs.jpcb.4c03766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/01/2024]
Abstract
Research on antimicrobial peptides (AMPs) has been conducted as a solution to overcome antibiotic resistance. In particular, the synergistic effect that appears when two or more AMPs are used in combination has been observed. To find an effective synergistic combination, it is necessary to understand the underlying mechanism. However, a consistent explanation for this phenomenon has not yet been provided due to limitations in experimentally determining or predicting the structure of the heteroaggregates formed by the interactions between different AMPs and the interaction of the aggregate surface with the lipid membrane surface. In this study, we conducted molecular dynamics simulations for two heterogeneous aggregates of melittin-indolicidin and pexiganan-indolicidin to observe their structures in the solution phase and their interactions with the lipid membrane. We aimed to determine how the surfaces of these aggregates interact with the lipid membrane. Due to the different amino acid residue sequence characteristics of melittin and pexiganan, we found that when the two AMPs bind to indolicidin, they form aggregates with completely different structural characteristics. Accordingly, the sequence characteristics of pexiganan, which exhibits a relatively unstable structure compared to melittin in aqueous solution or on lipid membranes, allow for a more stable interaction with the lipid membrane when forming aggregates with indolicidin, effectively inhibiting the integrity of the lipid membranes. We also found that the amino acid residues forming the surface of the AMP aggregate show differential binding strengths to different lipid species forming the lipid membrane, thereby disrupting the membrane in a way that weakens its integrity. Through this, we provided insight into the basic principle of how the synergistic effect of AMPs occurs.
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Affiliation(s)
- Jeseong Yoon
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Youngbeom Jo
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Seokmin Shin
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea
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Shukri A, Carroll AC, Collins R, Charih F, Wong A, Biggar KK. Systematic in vitro optimization of antimicrobial peptides against Escherichia coli. JAC Antimicrob Resist 2024; 6:dlae096. [PMID: 38966332 PMCID: PMC11220656 DOI: 10.1093/jacamr/dlae096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 05/21/2024] [Indexed: 07/06/2024] Open
Abstract
Objectives Antimicrobial resistance is a growing concern and claims over 1 million lives per year. The discovery of new antimicrobial drugs is expensive and often generates low profitability, with very low success rates. One way to combat this is by the improvement of known antimicrobials, such as antimicrobial peptides (AMPs). The aim of this study was to improve the antimicrobial activities of two known AMPs, UyCT3 and indolicidin, with the use of peptide libraries and growth curves. Methods Peptide permutation libraries were synthesized for two AMPs, indolicidin and UyCT3, which included 520 peptides. These peptides were subsequently tested against MG1655-K12, to which subsequent peptide design was performed, then tested against three clinically Gram-negative relevant drug-resistant isolates. Best-performing candidates were subjected to a haemolysis assay for toxicity validation. Results Single amino acid permutations of UyCT3 and indolicidin were sufficient to inhibit growth of MG1655-K12, and subsequent generations of peptide design were able to inhibit growth of clinical isolates at concentrations as low as 5 µM. Our best-performing AMP, UyCT3I5A, W6Y, K10I, F13I, was not seen to be toxic towards sheep RBCs. Conclusions The efficacy of the AMPs improved with the use of our peptide library technology, whereby an AMP was found that inhibited bacterial growth of clinical Gram-negative isolates 4-fold better than its WT counterpart.
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Affiliation(s)
- Ali Shukri
- Institute of Biochemistry and Department of Biology, Carleton University, Ottawa, Ontario, Canada K1S 5B6
| | - Amanda C Carroll
- Institute of Biochemistry and Department of Biology, Carleton University, Ottawa, Ontario, Canada K1S 5B6
| | - Ryan Collins
- Institute of Biochemistry and Department of Biology, Carleton University, Ottawa, Ontario, Canada K1S 5B6
| | - Francois Charih
- Department of Systems and Computer Engineering, Carleton University, Ottawa, Ontario, Canada K1S 5B6
| | - Alex Wong
- Institute of Biochemistry and Department of Biology, Carleton University, Ottawa, Ontario, Canada K1S 5B6
| | - Kyle K Biggar
- Institute of Biochemistry and Department of Biology, Carleton University, Ottawa, Ontario, Canada K1S 5B6
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Keeratikunakorn K, Chanapiwat P, Aunpad R, Ngamwongsatit N, Kaeoket K. Effect of Antimicrobial Peptide BiF2_5K7K on Contaminated Bacteria Isolated from Boar Semen and Semen Qualities during Preservation and Subsequent Fertility Test on Pig Farm. Antibiotics (Basel) 2024; 13:579. [PMID: 39061261 PMCID: PMC11274119 DOI: 10.3390/antibiotics13070579] [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: 05/09/2024] [Revised: 06/19/2024] [Accepted: 06/21/2024] [Indexed: 07/28/2024] Open
Abstract
The purpose of this study was to determine the impact of an antimicrobial peptide, BiF2_5K7K, on semen quality and bacterial contamination in boar semen doses used for artificial insemination. A key factor affecting semen quality and farm production is bacterial contamination in semen doses. Using antibiotics in a semen extender seems to be the best solution for minimizing bacterial growth during semen preservation. However, concern regarding antibiotic-resistant microorganisms has grown globally. As a result, antimicrobial peptides have emerged as interesting alternative antimicrobial agents to replace the current antibiotics used in semen extenders. BiF2_5K7K is an antimicrobial peptide that can inhibit Gram-negative and Gram-positive bacteria isolated from boar semen and sow vaginal discharge. In this study, ten fresh boar semen samples were collected and diluted with one of two types of semen extender: with (positive control) or without (negative control) an antibiotic (i.e., gentamicin). The semen extender without an antibiotic contained antimicrobial peptide BiF2_5K7K at different concentrations (15.625, 31.25, 62.5, and 125 µg/mL). The samples were stored at 18 °C until use. Semen quality parameters were assessed on days 0, 1, 3, and 5, and the total bacterial count was also evaluated at 0, 24, 36, 48, and 72 h after storage. A fertility test on a pig farm was also performed via sow insemination with a commercial extender plus BiF2_5K7K at a concentration of 31.25 µg/mL. No significant difference was found in terms of semen quality on days 0 or 1. On days 3 and 5, the total motility, progressive motility, and viability remained normal in the 15.625 and 31.25 µg/mL groups. However, the sperm parameters decreased starting on day 3 for the 125 µg/mL group and on day 5 for the 62.5 µg/mL group. For total bacterial count at 0, 24, 36, 48, and 72 h, the lowest bacterial count was found in the positive control group, and the highest bacterial count was found in the negative control group compared with the other groups. Comparing antimicrobial peptide groups from 0 to 48 h, the lowest bacterial count was found in the 125 µg/mL group, and the highest bacterial count was found in the 15.625 µg/mL group. For the fertility test, artificial insemination was conducted by using a commercial extender plus BiF2_5K7K at a concentration of 31.25 µg/mL. The results showed a superior pregnancy rate, farrowing rate, and total number of piglets born compared with artificial insemination conducted using a commercial extender plus antibiotic. In conclusion, BiF2_5K7K can inhibit bacterial growth in extended boar semen for 24 h, and thereafter, the bacterial count slightly increases. However, the increase in the number of bacterial counts from days 0 to 3 had no negative effect on sperm quality in the positive control, 15.625, or 31.25 µg/mL groups. This indicates that BiF2_5K7K might be an antimicrobial peptide candidate with potential for use as an alternative antimicrobial agent to replace the conventional antibiotic used in boar semen extenders.
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Affiliation(s)
- Krittika Keeratikunakorn
- Semen Laboratory, Department of Clinical Sciences and Public Health, Faculty of Veterinary Science, Mahidol University, 999 Phuttamonthon 4 Rd., Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand; (K.K.); (P.C.)
| | - Panida Chanapiwat
- Semen Laboratory, Department of Clinical Sciences and Public Health, Faculty of Veterinary Science, Mahidol University, 999 Phuttamonthon 4 Rd., Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand; (K.K.); (P.C.)
| | - Ratchaneewan Aunpad
- Graduate Program in Biomedical Sciences, Faculty of Allied Health Sciences, Thammasat University, Rangsit Campus, Klong Luang, Pathumthani 12120, Thailand;
| | - Natharin Ngamwongsatit
- Department of Clinical Sciences and Public Health, Faculty of Veterinary Science, Mahidol University, 999 Phuttamonthon 4 Rd., Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand;
- Laboratory of Bacteria, Veterinary Diagnostic Center, Faculty of Veterinary Science, Mahidol University, 999 Phuttamonthon 4 Rd., Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand
| | - Kampon Kaeoket
- Semen Laboratory, Department of Clinical Sciences and Public Health, Faculty of Veterinary Science, Mahidol University, 999 Phuttamonthon 4 Rd., Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand; (K.K.); (P.C.)
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Amer L, Retout M, Jokerst JV. Activatable prodrug for controlled release of an antimicrobial peptide via the proteases overexpressed in Candida albicans and Porphyromonas gingivalis. Theranostics 2024; 14:1781-1793. [PMID: 38389835 PMCID: PMC10879876 DOI: 10.7150/thno.91165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 02/11/2024] [Indexed: 02/24/2024] Open
Abstract
Candida albicans and Porphyromonas gingivalis are prevalent in the subgingival area where the frequency of fungal colonization increases with periodontal disease. Candida's transition to a pathogenic state and its interaction with P. gingivalis exacerbate periodontal disease severity. However, current treatments for these infections differ, and combined therapy remains unexplored. This work is based on an antimicrobial peptide that is therapeutic and induces a color change in a nanoparticle reporter. Methods: We built and characterized two enzyme-activatable prodrugs to treat and detect C. albicans and P. gingivalis via the controlled release of the antimicrobial peptide. The zwitterionic prodrug quenches the antimicrobial peptide's activity until activation by a protease inherent to the pathogens (SAP9 for C. albicans and RgpB for P. gingivalis). The toxicity of the intact prodrugs was evaluated against fungal, bacterial, and mammalian cells. Therapeutic efficacy was assessed through microscopy, disk diffusion, and viability assays, comparing the prodrug to the antimicrobial peptide alone. Finally, we developed a colorimetric detection system based on the aggregation of plasmonic nanoparticles. Results: The intact prodrugs showed negligible toxicity to cells absent a protease trigger. The therapeutic impact of the prodrugs was comparable to that of the antimicrobial peptide alone, with a minimum inhibitory concentration of 3.1 - 16 µg/mL. The enzymatic detection system returned a detection limit of 10 nM with gold nanoparticles and 3 nM with silver nanoparticles. Conclusion: This approach offers a convenient and selective protease sensing and protease-induced treatment mechanism based on bioinspired antimicrobial peptides.
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Affiliation(s)
- Lubna Amer
- Program in Materials Science and Engineering, University of California, San Diego, La Jolla, CA 92093, United States
| | - Maurice Retout
- Department of NanoEngineering, University of California, San Diego, La Jolla, CA 92093, United States
| | - Jesse V. Jokerst
- Program in Materials Science and Engineering, University of California, San Diego, La Jolla, CA 92093, United States
- Department of NanoEngineering, University of California, San Diego, La Jolla, CA 92093, United States
- Department of Radiology, University of California, San Diego, La Jolla, CA 92093, United States
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Amer L, Retout M, Jokerst JV. Activatable prodrug for controlled release of an antimicrobial peptide via the proteases overexpressed in Candida albicans and Porphyromonas gingivalis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.27.568833. [PMID: 38076788 PMCID: PMC10705279 DOI: 10.1101/2023.11.27.568833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/05/2024]
Abstract
We report the controlled release of an antimicrobial peptide using enzyme-activatable prodrugs to treat and detect Candida albicans and Porphyromonas gingivalis . Our motivation lies in the prevalence of these microorganisms in the subgingival area where the frequency of fungal colonization increases with periodontal disease. This work is based on an antimicrobial peptide that is both therapeutic and induces a color change in a nanoparticle reporter. This antimicrobial peptide was then built into a zwitterionic prodrug that quenches its activity until activation by a protease inherent to these pathogens of interest: SAP9 or RgpB for C. albicans and P. gingivalis , respectively. We first confirmed that the intact zwitterionic prodrug has negligible toxicity to fungal, bacterial, and mammalian cells absent a protease trigger. Next, the therapeutic impact was assessed via disk diffusion and viability assays and showed a minimum inhibitory concentration of 3.1 - 16 µg/mL, which is comparable to the antimicrobial peptide alone (absent integration into prodrug). Finally, the zwitterionic design was exploited for colorimetric detection of C. albicans and P. gingivalis proteases. When the prodrugs were cleaved, the plasmonic nanoparticles aggregated causing a color change with a limit of detection of 10 nM with gold nanoparticles and 3 nM with silver nanoparticles. This approach has value as a convenient and selective protease sensing and protease-induced treatment mechanism based on bioinspired antimicrobial peptides. Abstract Figure
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Canè C, Casciaro B, Di Somma A, Loffredo MR, Puglisi E, Battaglia G, Mellini M, Cappiello F, Rampioni G, Leoni L, Amoresano A, Duilio A, Mangoni ML. The antimicrobial peptide Esc(1-21)-1c increases susceptibility of Pseudomonas aeruginosa to conventional antibiotics by decreasing the expression of the MexAB-OprM efflux pump. Front Chem 2023; 11:1271153. [PMID: 37942400 PMCID: PMC10628714 DOI: 10.3389/fchem.2023.1271153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 10/09/2023] [Indexed: 11/10/2023] Open
Abstract
Introduction: The increase in bacterial strains resistant to conventional antibiotics is an alarming problem for human health and could lead to pandemics in the future. Among bacterial pathogens responsible for a large variety of severe infections there is Pseudomonas aeruginosa. Therefore, there is an urgent need for new molecules with antimicrobial activity or that can act as adjuvants of antibiotics already in use. In this scenario, antimicrobial peptides (AMPs) hold great promise. Recently, we characterized a frog-skin AMP derived from esculentin-1a, namely Esc(1-21)-1c, endowed with antipseudomonal activity without being cytotoxic to human cells. Methods: The combinatorial effect of the peptide and antibiotics was investigated through the checkerboard assay, differential proteomic and transcriptional analysis. Results: Here, we found that Esc(1-21)-1c can synergistically inhibit the growth of P. aeruginosa cells with three different antibiotics, including tetracycline. We therefore investigated the underlying mechanism implemented by the peptide using a differential proteomic approach. The data revealed a significant decrease in the production of three proteins belonging to the MexAB-OprM efflux pump upon treatment with sub-inhibitory concentration of Esc(1-21)-1c. Down-regulation of these proteins was confirmed by transcriptional analysis and direct measurement of their relative levels in bacterial cells by tandem mass spectrometry analysis in multiple reaction monitoring scan mode. Conclusion: These evidences suggest that treatment with Esc(1-21)-1c in combination with antibiotics would increase the intracellular drug content making bacteria more susceptible to the antibiotic. Overall, these results highlight the importance of characterizing new molecules able to synergize with conventional antibiotics, paving the way for the development of alternative therapeutic strategies based on AMP/antibiotic formulations to counteract the emergence of resistant bacterial strains and increase the use of "old" antibiotics in medical practice.
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Affiliation(s)
- Carolina Canè
- Department of Chemical Sciences, University of Naples “Federico II”, Naples, Italy
| | - Bruno Casciaro
- Laboratory Affiliated to Pasteur Italia-Fondazione Cenci Bolognetti, Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Angela Di Somma
- Department of Chemical Sciences, University of Naples “Federico II”, Naples, Italy
- CEINGE Biotecnologie Avanzate, Naples, Italy
| | - Maria Rosa Loffredo
- Laboratory Affiliated to Pasteur Italia-Fondazione Cenci Bolognetti, Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Elena Puglisi
- Laboratory Affiliated to Pasteur Italia-Fondazione Cenci Bolognetti, Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Gennaro Battaglia
- Department of Chemical Sciences, University of Naples “Federico II”, Naples, Italy
| | - Marta Mellini
- Department of Science, University “Roma Tre”, Rome, Italy
| | - Floriana Cappiello
- Laboratory Affiliated to Pasteur Italia-Fondazione Cenci Bolognetti, Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - Giordano Rampioni
- Department of Science, University “Roma Tre”, Rome, Italy
- IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Livia Leoni
- Department of Science, University “Roma Tre”, Rome, Italy
| | - Angela Amoresano
- Department of Chemical Sciences, University of Naples “Federico II”, Naples, Italy
- National Institute of Biostructure and Biosystems (INBB), Rome, Italy
| | - Angela Duilio
- Department of Chemical Sciences, University of Naples “Federico II”, Naples, Italy
- National Institute of Biostructure and Biosystems (INBB), Rome, Italy
| | - Maria Luisa Mangoni
- Laboratory Affiliated to Pasteur Italia-Fondazione Cenci Bolognetti, Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
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Costa NS, dos Anjos LR, de Souza JV, Brasil MCDA, Moreira VP, Graminha MAS, Lubec G, Gonzalez ERP, Cilli EM. Development of New Leishmanicidal Compounds via Bioconjugation of Antimicrobial Peptides and Antileishmanial Guanidines. ACS OMEGA 2023; 8:34008-34016. [PMID: 37744786 PMCID: PMC10515597 DOI: 10.1021/acsomega.3c04878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 08/16/2023] [Indexed: 09/26/2023]
Abstract
Leishmaniasis refers to a collection of diseases caused by protozoa from the Leishmania genus. These diseases, along with other parasitic afflictions, pose a significant public health issue, particularly given the escalating number of at-risk patients. This group includes immunocompromised individuals and those residing in impoverished conditions. The treatment of leishmaniasis is crucial, particularly in light of the mortality rate associated with nontreatment, which stands at 20-30,000 deaths per year globally. However, the therapeutic options currently available are limited, often ineffective, and potentially toxic. Consequently, the pursuit of new therapeutic alternatives is warranted. This study aims to design, synthesize, and evaluate the leishmanicidal activity of antimicrobial peptides functionalized with guanidine compounds and identify those with enhanced potency and selectivity against the parasite. Accordingly, three bioconjugates were obtained by using the solid-phase peptide synthesis protocol. Each proved to be more potent against intracellular amastigotes than their respective peptide or guanidine compounds alone and demonstrated higher selectivity to the parasites than to the host cells. Thus, the conjugation strategy employed with these compounds effectively contributes to the development of new molecules with leishmanicidal activity.
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Affiliation(s)
- Natalia
C. S. Costa
- Department
of Biochemistry and Organic Chemistry, Institute
of Chemistry, São Paulo State University (UNESP), 14800-060 Araraquara, São Paulo, Brazil
| | - Luana Ribeiro dos Anjos
- Fine
Organic Chemistry Lab, School of Sciences and Technology, São Paulo State University (UNESP), 19060-080 Presidente
Prudente, Sao Paulo, Brazil
| | - João Victor
Marcelino de Souza
- Department
of Biochemistry and Organic Chemistry, Institute
of Chemistry, São Paulo State University (UNESP), 14800-060 Araraquara, São Paulo, Brazil
| | | | - Vitor Partite Moreira
- Fine
Organic Chemistry Lab, School of Sciences and Technology, São Paulo State University (UNESP), 19060-080 Presidente
Prudente, Sao Paulo, Brazil
| | - Marcia A. S. Graminha
- School
of Pharmaceutical Sciences, São Paulo
State University (UNESP), 14800-903 Araraquara, São
Paulo, Brazil
| | - Gert Lubec
- Department
of Neuroproteomics, Paracelsus Medical University, 5020 Salzburg, Austria
| | - Eduardo Rene P. Gonzalez
- Fine
Organic Chemistry Lab, School of Sciences and Technology, São Paulo State University (UNESP), 19060-080 Presidente
Prudente, Sao Paulo, Brazil
| | - Eduardo Maffud Cilli
- Department
of Biochemistry and Organic Chemistry, Institute
of Chemistry, São Paulo State University (UNESP), 14800-060 Araraquara, São Paulo, Brazil
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Lazar V, Oprea E, Ditu LM. Resistance, Tolerance, Virulence and Bacterial Pathogen Fitness-Current State and Envisioned Solutions for the Near Future. Pathogens 2023; 12:pathogens12050746. [PMID: 37242416 DOI: 10.3390/pathogens12050746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/16/2023] [Accepted: 05/19/2023] [Indexed: 05/28/2023] Open
Abstract
The current antibiotic crisis and the global phenomena of bacterial resistance, inherited and non-inherited, and tolerance-associated with biofilm formation-are prompting dire predictions of a post-antibiotic era in the near future. These predictions refer to increases in morbidity and mortality rates as a consequence of infections with multidrug-resistant or pandrug-resistant microbial strains. In this context, we aimed to highlight the current status of the antibiotic resistance phenomenon and the significance of bacterial virulence properties/fitness for human health and to review the main strategies alternative or complementary to antibiotic therapy, some of them being already clinically applied or in clinical trials, others only foreseen and in the research phase.
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Affiliation(s)
- Veronica Lazar
- Department of Botany and Microbiology, Faculty of Biology, University of Bucharest, 1-3 Portocalelor Street, 060101 Bucharest, Romania
| | - Eliza Oprea
- Department of Botany and Microbiology, Faculty of Biology, University of Bucharest, 1-3 Portocalelor Street, 060101 Bucharest, Romania
| | - Lia-Mara Ditu
- Department of Botany and Microbiology, Faculty of Biology, University of Bucharest, 1-3 Portocalelor Street, 060101 Bucharest, Romania
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