Peptide damage under Fenton conditions is sequence-dependent

Area of Science:

• Biochemistry
• Chemical Biology
• Proteomics

Background:

• The Fenton reaction, involving iron and hydrogen peroxide, generates highly reactive hydroxyl radicals.
• Hydroxyl radicals are known to cause oxidative damage to biomolecules, including peptides.
• Understanding peptide susceptibility to oxidative stress is crucial for various biological and chemical applications.

Purpose of the Study:

• To investigate the differential susceptibility of peptides to oxidative damage under Fenton conditions.
• To identify specific amino acid compositions that correlate with increased peptide degradation.

Main Methods:

• A large one-bead-one-compound peptide library (29,791 members) was synthesized.
• The peptide library was subjected to Fenton reaction conditions (FeCl(3), sodium ascorbate, H(2)O(2)).
• Peptide damage was assessed to determine the extent of degradation.

Main Results:

• Peptides containing two or more acidic amino acids exhibited significantly greater damage compared to other peptides.
• The presence of acidic residues appears to sensitize peptides to hydroxyl radical attack.
• This suggests a structure-activity relationship in peptide oxidative stability.

Conclusions:

• Acidic amino acid content is a key determinant of peptide vulnerability to Fenton-mediated oxidative damage.
• These findings have implications for peptide stability in biological systems and in the design of peptide-based therapeutics.
• Further research can explore protective strategies for peptides rich in acidic residues.