Oxidative Modifications:
1. Side Chain Oxidation:
Specific amino acids (e.g., cysteine, methionine) are susceptible to oxidation.
This alters their chemical properties and can disrupt protein function by affecting enzymatic activity or binding interactions.
2. Backbone Oxidation:
Leads to fragmentation of the protein, altering its structure and solubility.
3. Cross-linking:
Free radicals can induce the formation of covalent bonds between proteins, resulting in aggregates that the cell cannot easily clear.
This is a hallmark of several age-related diseases.
Consequences:
Altered cellular signaling and enzymatic activity.
Misfolded proteins and aggregates, contributing to diseases like Alzheimer's and Parkinson's.