Conjugation of Ctx(Ile(21))-Ha Antimicrobial Peptides to Chitosan Ultrathin Films by N-Acetylcysteine Improves Peptide Physicochemical Properties and Enhances Biological Activity

Author(s)

Roque-Borda, Cesar Augusto ; Antunes, Bruna Fernandes ; Borgues, Anna Beatriz Toledo ; Pontes, Janaina Teixeira Costa de ; Meneguin, Andreia Bagliotti ; Chorilli, Marlus ; Trovatti, Eliane ; Teixeira, Silvio Rainho ; Pavan, Fernando Rogerio ; Vicente, Eduardo Festozo

• Document type: Journal article
• Source: ACS OMEGA; v. 7, n. 32, p. 10-pg., 2022-08-16.

Abstract

The importance of obtaining new compounds with improved antimicrobial activity is a current trend and challenge. Some polymers such as chitosan have shown promising bactericidal properties when they are structurally modified, which is due to the binding versatility provided by their free amines. Likewise, antimicrobial peptides (AMPs) have received attention in recent years because of their bactericidal activity that is similar to or even better than that of conventional drugs, and they exhibit a low induction rate of antimicrobial resistance. Herein, the modified AMP Ctx(Ile21)-Ha-Ahx-Cys was conjugated to chitosan using N- acetylcysteine as an intermediate by the carbodiimide method. Films were prepared using protonated chitosan in 1% acetic acid and Ctx(Ile21)-Ha-Ahx-Cys AMP dissolved in N-acetylcysteine-chitosan; 1.6 mmol of ethylcarbodiimide hydrochloride, 1.2 mmol of N-hydroxysulfosucchimide, and 0.1 mol L -1of N- morpholino)ethanesulfonic acid buffer at pH 6.5 by continuous stirring at 100 x g for 10 min at 37 & DEG;C. Physicochemical properties were evaluated by Fourier-transform infrared spectroscopy, differential scanning calorimetry/thermogravimetric analysis, and X-ray diffraction to determine the mechanical properties, solubility, morphology, and thickness. Furthermore, the antimicrobial activities of chitosan-based conjugated films were evaluated againstStaphylococcus aureus,Pseudomonas aeruginosa,SalmonellaTyphimurium, and Escherichia coli. The results showed that the conjugation of a potent AMP could further increase its antibacterial activity and maintain its stable physicochemical properties. Therefore, the developed peptide-chitosan conjugate could be applied as an additive in surgical procedures to prevent and combat bacterial infection. (AU)

• FAPESP's process: 20/16573-3 - In vitro and in vivo studies of antimicrobial peptide B1CTcu5 analogs encapsulated in colon-specific microparticles against Mycobacterium tuberculosis
• Grantee: Cesar Augusto Roque Borda
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 20/13497-4 - Search for the mechanism of action and therapeutic effect of new classes of drugs against Mycobacterium tuberculosis
• Grantee: Fernando Rogério Pavan
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/25707-3 - Application of the antimicrobial peptide Ctx(Ile21)-Ha and its conjugates in different formulations as a nutritional additive in laying hens
• Grantee: Cesar Augusto Roque Borda
• Support Opportunities: Scholarships in Brazil - Master