AI Article Synopsis

  • The text discusses the urgent need for new antibiotics due to rising microbial resistance, highlighting antimicrobial peptides (AMPs) like AurH1, a modified version of Aurein1.2, for their unique antifungal properties.
  • In this study, AurH1 was synthetically modified into two forms: acylated (Ac-AurH1) and amidated (AurH1-NH), with tests conducted on their antifungal activity, cytotoxicity, impact on cancer cells, and effects in human serum.
  • Results indicated that amidation at AurH1's C-terminal enhances its antifungal effectiveness and cytotoxicity without altering its mechanism of action, suggesting promise for further research in animal studies.

Article Abstract

Background: The increasing growth of microbial resistance threatens the health of human societies. Therefore, the discovery and design of new antibiotics seem necessary. Today, antimicrobial peptides (AMPs) are receiving attention due to their unique properties. In our previous studies, exclusive antifungal effects of AurH1, which is a truncated and modified form of Aurein1.2, were synthesized. In this study, AurH1 antifungal peptide was synthesized into acylated (Ac-AurH1) and amidated (AurH1-NH) derivatives, and their antifungal activity, cytotoxicity, anticancer activity, hemolytic effects were investigated. Finally, the time- of killing, the action mechanism of amidated and acylated peptides, and the effects of salts and human serum on their antimicrobial potency were determined. All the results obtained about these peptides were compared with the AurH1 without chemical modifications.

Results: The results showed that amidation at the C-terminal of AurH1 compared to acylation at the N-terminal of it can improve the antifungal properties and cytotoxicity of AurH1. The results showed that AurH1 amidation can maintain the antifungal activity of this peptide in the culture medium containing specific dilutions of human serum compared to the intact AurH1. Also, the amidation of the C-terminal of AurH1 could not affect the mechanism of action and its time -of killing.

Conclusion: As a result, the amidation of the C-terminal of the AurH1 is a suitable strategy to improve its antifungal properties and cytotoxicity. This modification can enhance its properties for animal studies.

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Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC10633902PMC
http://dx.doi.org/10.1186/s12866-023-03090-7DOI Listing

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