Showing 3 results for Antimicrobial Peptide
Safieh Sofian, Hossein Nadri Manesh, Abdolali Alizadeh,
Volume 11, Issue 4 (12-2008)
Abstract
Background: Aurein 1/2 is a 13-residue peptide with a vast antimicrobial and anticancer activity. Two- dimensional NMR spectroscopy of peptide solubilized in the 70% TFE (2, 2, 2-Trifluoroethanol) indicated an alpha-helical conformation. The mechanism of its action is not yet fully recognized. This study was designed to improve the antimicrobial activity and relationship between subsequence-activity in Aurein 1/2 and its analoges. Analogs of this peptide were designed and synthesized. Methods and Materials: The G1F3/RW and F3W analogs and retro - analog were synthesized with solide phase and purified via HPLC and lyophilized. These analogs were assayed by several methods: amino acid analysis, HPLC, and electrospray mass spectrometry. Then antimicrobial activity of the peptides was assessed by using the standard microdilution susceptibility test. Results: The data demonstrated that G1F3/RW analog had a higher activity and results of test figure of minimum inhibitory concentration for F3W analog had three levels. But the native, F3W analog and retro-analog was inactive. Conclusion: The higher activity of G1F3/RW in compare to F3W may be related to the positive charge of Arg that leading stronger interaction with the negative charges on the membrane surface. The result showed that reversed direction of aurein 1/2 significantly effects on activity of the peptide. It is also suggested inactivation of reto-analog amino acid type, position and size should be cautious for peptides designed as drug because it may be effect to control dimerization and maintenance of antimicrobial activity of the peptide.
Mohammadbagher Salehi, Mojtaba Saadati, Babak Barati, Mahdi Saberi, Gholamreza Olaad, Aliasghar Rahimi,
Volume 14, Issue 6 (1-2012)
Abstract
Background: The major aim of this study was synthesis and assay of antimicrobial activity of peptide D28 and its new analogues derivatives as dimeric peptides.
Materials and Methods: Three antimicrobial peptides known as D28, Di-D28-Lys,Di-Cys-D28 including 20, 41, 42 residues were synthesized respectively. For peptide synthesis, solid phase peptide synthesis method using blocked amino acids with flourenyl methoxy carbonyl group and for peptide purification HPLC were used. Peptides compositions were confirmed by amino acid analysis and SDS-PAGE electrophoresis. Antimicrobial tests against Staphylococcus aureus and Pseudomonas aeruginosa were performed as disk and well diffusion on plate and by adding to liquid broth culture (Broth macrodilution) in different concentrations.
Results: Three required peptides (D28, Di-D28-Lys, Di-Cys-D28) successfully were synthesized. All three peptides were effective against S. aureus, but Di-Cys-D28 on the contrary to two other ones, showed no antimicrobial activity against P. aeruginosa. The inhibitory activity of Di-D28-Lys against P. aeruginosa was more than that of D28 peptide.
Conclusion: Improvement of antimicrobial peptides activity through dimerization depends on the methods of dimerization and the strain of bacterium. Di-D28-Lys peptide in comparison with D28 and Di-Cys-D28 showed wide range and more antimicrobial activity. Therefore, Di-D28-Lys peptide could be a suitable antibiotic candidate for future studies.
Ali Ganji, Amir Mohammad Saeedi, Ali Ghazavi, Ghasem Mosayebi,
Volume 22, Issue 4 (9-2019)
Abstract
Cancer is one of the leading causes of death worldwide. Thus, it is important to find newer, more selective, and more effective therapies for this disease. One of these methods that have attracted many researchers is using anticancer peptides regarding their specificity, lower side effects, and higher effectiveness on the cancer cells. One type of anticancer peptides is antimicrobial peptides. Although they have already been studied and introduced as potential agents to fight infectious diseases, only recently they have been used as a new way of cancer treatment. For decades, antimicrobial peptides have been considered a component of the native immune system; however, they can also be used as anticancer peptides due to their mechanisms and properties. This new therapeutic approach can provide a promising pathway for optimal cancer treatment with fewer side effects.
