Synthesis of Cyclic Hexapeptides via the Hydrazide Method and Evaluation of Their Antibacterial Activities
Abstract
:1. Introduction
2. Results
2.1. Synthesis of Cyclic Hexapeptides
2.2. Antimicrobial Assay of 11 Cyclic Hexapeptides
Comparative Analysis of Antimicrobial Peptide Efficacy
2.3. Hemolytic Assay
2.4. Time-Dependent Growth Kinetics of Cy-f2 Against Klebsiella pneumoniae
2.5. Scanning Electron Microscopy Analysis of Cy-f2 and Cy-f4 Effects on Klebsiella pneumoniae and Candida tropicalis
2.6. Stability of Cy-f1, Cy-f2, and Cy-f4
3. Discussion
4. Materials and Methods
4.1. Reagents and Instruments
4.2. Peptides Synthesis and Characterization
4.2.1. Synthesis of Cyclic Hexapeptides
4.2.2. Peptide Molecular Weight Identification
4.3. Biological Studies
4.3.1. Antibacterial Assay
4.3.2. Hemolytic Assay
− O.D of PBS control) × 100%
4.3.3. Time-Dependent Growth Kinetics
4.3.4. Scanning Electron Microscope (SEM)
4.4. Stability
4.4.1. Simulated Gastric Fluid Stability
4.4.2. Simulated Intestinal Fluid Stability
4.4.3. Thermal Stability
4.5. Structural Prediction by AlphaFold2
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Peptide Name | Sequence | Theoretical M.W. (g/mol) | Experimental M.W. (g/mol) |
---|---|---|---|
Cy-f1 | c-[CLLKIF] | 717.98 | 717.97 |
Cy-f2 | c-[CRLKIF] | 761.01 | 761.03 |
Cy-f3 | c-[CKLKIF] | 733.00 | 733.22 |
Cy-f4 | c-[CKLRWF] | 834.06 | 834.22 |
Cy-f5 | c-[CRKPII] | 710.95 | 711.35 |
Cy-f6 | c-[CRKPIV] | 696.92 | 697.25 |
Cy-f7 | c-[CRKPVL] | 696.92 | 697.53 |
Cy-f8 | c-[CRIVVR] | 726.95 | 727.34 |
Cy-f9 | c-[CIRPIL] | 695.94 | 696.75 |
Cy-f10 | c-[CRVIIR] | 740.98 | 741.27 |
Cy-f11 | c-[CIRPII] | 695.94 | 696.13 |
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Cui, Y.; Liu, M.; Ruan, B.; Liao, Z.; Tang, X.; Zhangsun, D.; Wu, Y.; Luo, S. Synthesis of Cyclic Hexapeptides via the Hydrazide Method and Evaluation of Their Antibacterial Activities. Molecules 2025, 30, 2444. https://doi.org/10.3390/molecules30112444
Cui Y, Liu M, Ruan B, Liao Z, Tang X, Zhangsun D, Wu Y, Luo S. Synthesis of Cyclic Hexapeptides via the Hydrazide Method and Evaluation of Their Antibacterial Activities. Molecules. 2025; 30(11):2444. https://doi.org/10.3390/molecules30112444
Chicago/Turabian StyleCui, Yunfei, Meng Liu, Binghui Ruan, Zhouyuji Liao, Xue Tang, Dongting Zhangsun, Yong Wu, and Sulan Luo. 2025. "Synthesis of Cyclic Hexapeptides via the Hydrazide Method and Evaluation of Their Antibacterial Activities" Molecules 30, no. 11: 2444. https://doi.org/10.3390/molecules30112444
APA StyleCui, Y., Liu, M., Ruan, B., Liao, Z., Tang, X., Zhangsun, D., Wu, Y., & Luo, S. (2025). Synthesis of Cyclic Hexapeptides via the Hydrazide Method and Evaluation of Their Antibacterial Activities. Molecules, 30(11), 2444. https://doi.org/10.3390/molecules30112444