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Lu H, Wang C, Lu W, Li X, Wang G, Dong W, Wang X, Chen H, Tan C. Antibacterial efficacy and mechanism of Cyprinus carpio chemokine-derived L-10 against multidrug-resistant Escherichia coli infections. Int J Antimicrob Agents 2024; 63:107104. [PMID: 38325720 DOI: 10.1016/j.ijantimicag.2024.107104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/02/2024] [Accepted: 01/29/2024] [Indexed: 02/09/2024]
Abstract
OBJECTIVES Antimicrobial resistance has raised concerns regarding untreatable infections and poses a growing threat to public health. Rational design of new AMPs is an ideal solution to this threat. METHODS In this study, we designed, modified, and synthesised an excellent AMP, L-10, based on the original sequence of the Cyprinus carpio chemokine. All experimental data were presented as the mean ± standard deviation (SD), and the two-tailed unpaired T-test method was used to analyze all data. RESULTS L-10 exhibited excellent antibacterial activity with negligible toxicity and improved the efficacy of a broad class of antibiotics against MDR Gram-negative pathogens, including tetracycline, meropenem, levofloxacin, and rifampin. Mechanistic studies have suggested that L-10 targets the bacterial membrane components, LPS and PG, to disrupt bacterial membrane integrity, thereby exerting antibacterial effects and enhancing the efficacy of antibiotics. Moreover, in animal infection models, L-10 significantly increased the survival rate of infected animals and effectively reduced the tissue bacterial load and inflammatory factor levels. In addition to its direct antibacterial activity, L-10 dramatically reduced pulmonary pathological alterations in a mouse model of endotoxemia and suppressed LPS-induced proinflammatory cytokines in vitro and in vivo. Lastly, L-10 was successfully expressed in Pichia pastoris and maintained antimicrobial activity against MDR Gram-negative pathogens in vivo and in vitro. CONCLUSION Collectively, these results reveal the potential of L-10 as an ideal candidate against MDR bacterial infections and provide new insights into the design, development, and clinical application of AMPs.
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Affiliation(s)
- Hao Lu
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China; Hubei Hongshan Laboratory, Wuhan, Hubei, China
| | - Chenchen Wang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China; Hubei Hongshan Laboratory, Wuhan, Hubei, China
| | - Wenjia Lu
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China; Hubei Hongshan Laboratory, Wuhan, Hubei, China
| | - Xiaodan Li
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China; Hubei Hongshan Laboratory, Wuhan, Hubei, China
| | - Gaoyan Wang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China; Hubei Hongshan Laboratory, Wuhan, Hubei, China
| | - Wenqi Dong
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China; Hubei Hongshan Laboratory, Wuhan, Hubei, China
| | - Xiangru Wang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China; Hubei Hongshan Laboratory, Wuhan, Hubei, China; Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan, Hubei, China; Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei, China
| | - Huanchun Chen
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China; Hubei Hongshan Laboratory, Wuhan, Hubei, China; Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan, Hubei, China; Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei, China
| | - Chen Tan
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China; Hubei Hongshan Laboratory, Wuhan, Hubei, China; Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan, Hubei, China; Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei, China.
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Wang A, Zhou M, Chen Q, Jin H, Xu G, Guo R, Wang J, Lai R. Functional Analyses of Three Targeted DNA Antimicrobial Peptides Derived from Goats. Biomolecules 2023; 13:1453. [PMID: 37892141 PMCID: PMC10605153 DOI: 10.3390/biom13101453] [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: 07/23/2023] [Revised: 09/03/2023] [Accepted: 09/14/2023] [Indexed: 10/29/2023] Open
Abstract
With the increase in drug-resistant bacteria, new antibacterial drugs have emerged as a prominent area of research and development. Antimicrobial peptides (AMPs), as innate immune agents, have garnered significant attention due to their potent, rapid, and broad-spectrum antibacterial activity. This study focused on investigating the functionality of three AMPs (CATH 1, CATH 2, and MAP34-B) derived from goat submandibular glands. Among these AMPs, CATH 2 and MAP34-B exhibited direct antibacterial activity against both Gram-negative and Gram-positive bacteria, primarily targeting the bacterial membrane. Additionally, these two AMPs were found to have the potential to induce reactive oxygen species (ROS) production in bacterial cells and interact with bacterial genome DNA, which may play a crucial role in their mechanisms of action. Furthermore, both CATH 1 and CATH 2 demonstrated significant antioxidant activity, and all three AMPs exhibited potential anti-inflammatory activity. Importantly, the cytotoxic activity of these AMPs against mammalian cells was found to be weak, and their hemolytic activity was extremely low. Overall, the characteristics of these three AMPs found in goat submandibular glands offer new insights for the study of host protection from an immunological perspective. They hold promise as potential candidates for the development of novel antibacterial agents, particularly in the context of combating drug-resistant bacteria.
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Affiliation(s)
- Aili Wang
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (A.W.)
| | - Mengying Zhou
- Suzhou Guangji Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou 215137, China
| | - Qian Chen
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (A.W.)
| | - Hui Jin
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (A.W.)
| | - Gaochi Xu
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (A.W.)
| | - Ruiyin Guo
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (A.W.)
| | - Jianmin Wang
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian 271000, China;
| | - Ren Lai
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (A.W.)
- Key Laboratory of Bioactive Peptides of Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Sino-African Joint Research Center and Engineering Laboratory of Peptides, Kunming Institute of Zoology, Kunming 650107, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Zhang J, Gu S, Zhang T, Wu Y, Ma J, Zhao L, Li X, Zhang J. Characterization and antibacterial modes of action of bacteriocins from Bacillus coagulans CGMCC 9951 against Listeria monocytogenes. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113272] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Chou S, Li Q, Wu H, Li J, Chang YF, Shang L, Li J, Wang Z, Shan A. Selective Antifungal Activity and Fungal Biofilm Inhibition of Tryptophan Center Symmetrical Short Peptide. Int J Mol Sci 2021; 22:ijms22158231. [PMID: 34360998 PMCID: PMC8348200 DOI: 10.3390/ijms22158231] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 07/19/2021] [Accepted: 07/19/2021] [Indexed: 11/24/2022] Open
Abstract
Candida albicans, an opportunistic fungus, causes dental caries and contributes to mucosal bacterial dysbiosis leading to a second infection. Furthermore, C.albicans forms biofilms that are resistant to medicinal treatment. To make matters worse, antifungal resistance has spread (albeit slowly) in this species. Thus, it has been imperative to develop novel, antifungal drug compounds. Herein, a peptide was engineered with the sequence of RRFSFWFSFRR-NH2; this was named P19. This novel peptide has been observed to exert disruptive effects on fungal cell membrane physiology. Our results showed that P19 displayed high binding affinity to lipopolysaccharides (LPS), lipoteichoic acids (LTA) and the plasma membrane phosphatidylinositol (PI), phosphatidylserine (PS), cardiolipin, and phosphatidylglycerol (PG), further indicating that the molecular mechanism of P19 was not associated with the receptor recognition, but rather related to competitive interaction with the plasma membrane. In addition, compared with fluconazole and amphotericin B, P19 has been shown to have a lower potential for resistance selection than established antifungal agents.
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Affiliation(s)
- Shuli Chou
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China; (S.C.); (Q.L.); (H.W.); (J.L.); (L.S.); (J.L.); (Z.W.)
| | - Qiuke Li
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China; (S.C.); (Q.L.); (H.W.); (J.L.); (L.S.); (J.L.); (Z.W.)
| | - Hua Wu
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China; (S.C.); (Q.L.); (H.W.); (J.L.); (L.S.); (J.L.); (Z.W.)
| | - Jinze Li
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China; (S.C.); (Q.L.); (H.W.); (J.L.); (L.S.); (J.L.); (Z.W.)
| | - Yung-Fu Chang
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA;
| | - Lu Shang
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China; (S.C.); (Q.L.); (H.W.); (J.L.); (L.S.); (J.L.); (Z.W.)
| | - Jiawei Li
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China; (S.C.); (Q.L.); (H.W.); (J.L.); (L.S.); (J.L.); (Z.W.)
| | - Zhihua Wang
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China; (S.C.); (Q.L.); (H.W.); (J.L.); (L.S.); (J.L.); (Z.W.)
| | - Anshan Shan
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China; (S.C.); (Q.L.); (H.W.); (J.L.); (L.S.); (J.L.); (Z.W.)
- Correspondence:
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Jiang R, Zhang P, Wu X, Wang Y, Rehman T, Yao X, Luo Y, Yang Z. Expression of antimicrobial peptide Cecropin P1 in Saccharomyces cerevisiae and its antibacterial and antiviral activity in vitro. ELECTRON J BIOTECHN 2021. [DOI: 10.1016/j.ejbt.2020.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Zhu N, Zhong C, Liu T, Zhu Y, Gou S, Bao H, Yao J, Ni J. Newly designed antimicrobial peptides with potent bioactivity and enhanced cell selectivity prevent and reverse rifampin resistance in Gram-negative bacteria. Eur J Pharm Sci 2021; 158:105665. [DOI: 10.1016/j.ejps.2020.105665] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 11/18/2020] [Accepted: 11/26/2020] [Indexed: 01/10/2023]
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Cui Q, Xu QJ, Liu L, Guan LL, Jiang XY, Inam M, Kong LC, Ma HX. Preparation, Characterization and Pharmacokinetic Study of N-Terminal PEGylated D-Form Antimicrobial Peptide OM19r-8. J Pharm Sci 2020; 110:1111-1119. [PMID: 33129837 DOI: 10.1016/j.xphs.2020.10.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/26/2020] [Accepted: 10/26/2020] [Indexed: 02/07/2023]
Abstract
Recently, new cationic antibacterial peptide OM19R has been designed with low minimum inhibitory concentration (MIC) values against some gram-negative bacteria, such as Escherichia coli, Salmonella, and Shigella. However, this hybrid peptide, like most antibacterial peptides, has low enzyme stability and short half-life, which, in turn, increases the drug's cost. In this study, an antibacterial peptide (OM19r-8) was obtained containing some D-Arg amino acids. The new preparations were carried out through the replacement of l-Arginine by d-Arginine and the addition of PEG chains. Firstly, eight OM19r series of antibacterial peptides were obtained by designing D-Arg. Then, a polyethylene glycol-modified product mPEG5-butyrALD-OM19r-8 (mPEG5-OM19r-8) was isolated and purified by reverse-phase high-performance liquid chromatography (RT-HPLC). The enzyme stability test showed that the resistance of antibacterial peptide OM19r-8 to protease degradation increased by 4-32-fold. Moreover, the Time-kill studies showed that the germicidal kinetics curves of mPEG5-OM19r-8 and OM19r-8 to Escherichia coli had a similar trend, thus suggesting that PEG modification has an acceptable effect on the activity of the original peptide. Furthermore, the elimination of half-life (28.09 ± 2.81min) of mPEG5-OM19r-8, and the area under the drug concentration-time curve (2686.48 ± 651.36min∗ug/ml) was significantly prolonged. The current study demonstrates an example that optimizes the AMP by utilizing L-to-D amino acid replacement and including PEG chains. These results provide useful data for the clinical application of the mPEG5-OM19r-8.
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Affiliation(s)
- Qi Cui
- College of Animal Science and Technology, Jilin Agricultural University, Xincheng Street No.2888, Changchun 130118, China
| | - Qi-Jun Xu
- College of Animal Science and Technology, Jilin Agricultural University, Xincheng Street No.2888, Changchun 130118, China
| | - Lei Liu
- College of Animal Science and Technology, Jilin Agricultural University, Xincheng Street No.2888, Changchun 130118, China
| | - Li-Li Guan
- College of Life Science and Technology, Jilin Agricultural University, Xincheng Street No.2888, Changchun 130118, China
| | - Xiu-Yun Jiang
- College of Animal Science and Technology, Jilin Agricultural University, Xincheng Street No.2888, Changchun 130118, China
| | - Muhammad Inam
- College of Animal Science and Technology, Jilin Agricultural University, Xincheng Street No.2888, Changchun 130118, China
| | - Ling-Cong Kong
- College of Animal Science and Technology, Jilin Agricultural University, Xincheng Street No.2888, Changchun 130118, China; The Key Laboratory of Animal Production, Product Quality and Security, Ministry of Education, Jilin Agricultural University, Xincheng Street No.2888, Changchun, Jilin, China.
| | - Hong-Xia Ma
- College of Animal Science and Technology, Jilin Agricultural University, Xincheng Street No.2888, Changchun 130118, China; The Key Laboratory of Animal Production, Product Quality and Security, Ministry of Education, Jilin Agricultural University, Xincheng Street No.2888, Changchun, Jilin, China.
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Maystrenko A, Feng Y, Akhtar N, Li J. The Addition of a Synthetic LPS-Targeting Domain Improves Serum Stability While Maintaining Antimicrobial, Antibiofilm, and Cell Stimulating Properties of an Antimicrobial Peptide. Biomolecules 2020; 10:E1014. [PMID: 32650576 PMCID: PMC7407491 DOI: 10.3390/biom10071014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 07/04/2020] [Accepted: 07/06/2020] [Indexed: 12/21/2022] Open
Abstract
Multi-drug resistant (MDR) bacteria and their biofilms are a concern in veterinary and human medicine. Protegrin-1 (PG-1), a potent antimicrobial peptide (AMP) with antimicrobial and immunomodulatory properties, is considered a potential alternative for conventional antibiotics. AMPs are less stable and lose activity in the presence of physiological fluids, such as serum. To improve stability of PG-1, a hybrid peptide, SynPG-1, was designed. The antimicrobial and antibiofilm properties of PG-1 and the PG-1 hybrid against MDR pathogens was analyzed, and activity after incubation with physiological fluids was compared. The effects of these peptides on the IPEC-J2 cell line was also investigated. While PG-1 maintained some activity in 25% serum for 2 h, SynPG-1 was able to retain activity in the same condition for up to 24 h, representing a 12-fold increase in stability. Both peptides had some antibiofilm activity against Escherichia coli and Salmonella typhimurium. While both peptides prevented biofilm formation of methicillin-resistant Staphylococcus aureus (MRSA), neither could destroy MRSA's pre-formed biofilms. Both peptides maintained activity after incubation with trypsin and porcine gastric fluid, but not intestinal fluid, and stimulated IPEC-J2 cell migration. These findings suggest that SynPG-1 has much better serum stability while maintaining the same antimicrobial potency as PG-1.
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Affiliation(s)
| | | | | | - Julang Li
- Animal Biosciences, University of Guelph, Guelph, ON N1G 2W1, Canada; (A.M.); (Y.F.); (N.A.)
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Chou S, Wang J, Shang L, Akhtar MU, Wang Z, Shi B, Feng X, Shan A. Short, symmetric-helical peptides have narrow-spectrum activity with low resistance potential and high selectivity. Biomater Sci 2019; 7:2394-2409. [PMID: 30919848 DOI: 10.1039/c9bm00044e] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Broad-spectrum antibiotics have, until now, been the mainstay of antibiotic therapy. However, the increasing threat of drug-resistant bacteria and the ecological imbalance of normal microbial communities have forced a reconsideration of the best strategies to treat such pathogens. Therefore, antibacterial agents with specific abilities of eliminating pathogens may provide long-term protection. Antimicrobial peptides (AMPs), which can be optimized by modifying their primary sequences, are regarded as potentially valuable in development of pathogen-specific agents. To obtain efficient narrow-spectrum AMPs, database-filtering technology, which filters the most probable amino acid composition, positive charge, sequence length and hydrophobic content of peptides against Gram-negative bacteria, was taken as the first step. Then, the filtered parameters were distributed and modified into an α-helical symmetrical structure by considering the structure-function relationship of synthesized antimicrobial peptides. Finally, short, safe and stable peptides against Escherichia coli, Salmonella pullorum and Pseudomonas aeruginosa were successfully identified. The potential peptides F1 and F4 showed low cell toxicity, low resistance potential and low salt sensitivity. CD spectroscopy of the peptides illustrated that F1 and F4 exhibited a tendency towards an α-helical structure in a membrane-mimetic environment. Indeed, fluorescence spectroscopy and electron microscopy analyses indicated that the shorter potential sequence F4 killed the bacteria by causing physical destruction of the bacterial membrane and cytosol leakage. In the mouse model test, F4 reduced the bacterial load in major organs and the cytokine (TNF-α, IL-6, and IL-1β) levels in serum significantly (P < 0.05). Collectively, this symmetric-helical distribution, dependent on database-filtering parameters, is a promising strategy for designing effective smart AMPs with high cell selectivity, and it also provides new insights into the design and optimization of pathogen-specific biomaterials.
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Affiliation(s)
- Shuli Chou
- Laboratory of Molecular Nutrition and Immunity, The Institute of Animal Nutrition, Northeast Agricultural University, Harbin, P. R. China.
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Design and Characterization of a Novel Hybrid Antimicrobial Peptide OM19R Based on Oncocin and MDAP-2. Int J Pept Res Ther 2019. [DOI: 10.1007/s10989-019-09984-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Zhong C, Liu T, Gou S, He Y, Zhu N, Zhu Y, Wang L, Liu H, Zhang Y, Yao J, Ni J. Design and synthesis of new N-terminal fatty acid modified-antimicrobial peptide analogues with potent in vitro biological activity. Eur J Med Chem 2019; 182:111636. [PMID: 31466017 DOI: 10.1016/j.ejmech.2019.111636] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 08/12/2019] [Accepted: 08/19/2019] [Indexed: 12/25/2022]
Abstract
Developing novel antimicrobial agents is a top priority in fighting against bacterial resistance. Thus, a series of new monomer and dimer peptides were designed and synthesized by conjugating fatty acids at the N-terminus of partial d-amino acid substitution analogues of anoplin and dimerization. The new peptides exhibited more efficient killing of gram-negative and gram-positive bacteria, including methicillin-resistant Staphylococcus aureus compared with the parent peptide anoplin, and the dimer peptides were superior to the monomer peptides. It was important that the new peptides displayed low impact on bacterial resistance development. In addition, the antimicrobial activities were not significantly influenced by a physiological salt environment. They also presented high stability in the presence of protease or serum. Almost all of the new peptides had better selectivity towards anionic bacterial membranes over zwitterionic mammalian cell membranes. Moreover, the new peptides displayed synergistic or additive effects when used together with the antibiotics rifampicin and polymyxin B. These results showed that the new peptides could also prevent the formation of bacterial biofilms. Furthermore, outer/inner membrane permeabilization and cytoplasmic membrane depolarization experiments revealed that the new peptides had strong membrane permeabilization and depolarization. Confocal laser scanning microscopy, flow cytometry analysis and scanning electron microscopy further demonstrated that the new peptides could damage the integrity of the bacterial membrane. Finally, a DNA-binding affinity assay showed that the new peptides could bind to bacterial DNA. In summary, the conjugation of fatty acids at the N-terminus of peptides and dimerization are promising strategies for obtaining potent antimicrobial agents.
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Affiliation(s)
- Chao Zhong
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, 730000, China; School of Pharmacy, Lanzhou University, Lanzhou, 730000, China
| | - Tianqi Liu
- School of Pharmacy, Lanzhou University, Lanzhou, 730000, China
| | - Sanhu Gou
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, 730000, China; School of Pharmacy, Lanzhou University, Lanzhou, 730000, China
| | - Yongtao He
- School of Pharmacy, Lanzhou University, Lanzhou, 730000, China
| | - Ningyi Zhu
- School of Pharmacy, Lanzhou University, Lanzhou, 730000, China
| | - Yuewen Zhu
- School of Pharmacy, Lanzhou University, Lanzhou, 730000, China
| | - Li Wang
- School of Pharmacy, Lanzhou University, Lanzhou, 730000, China
| | - Hui Liu
- School of Pharmacy, Lanzhou University, Lanzhou, 730000, China
| | - Yun Zhang
- School of Pharmacy, Lanzhou University, Lanzhou, 730000, China
| | - Jia Yao
- The First Hospital of Lanzhou University, Lanzhou, 730000, China
| | - Jingman Ni
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou, 730000, China; School of Pharmacy, Lanzhou University, Lanzhou, 730000, China.
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