Cysteinmodifikasjoner

Cysteinmodifikasjoner, or cysteine modifications, refer to the chemical alterations that occur on the amino acid cysteine within proteins. Cysteine is unique among amino acids due to its sulfur-containing side chain, which can form disulfide bonds with other cysteine residues or react with various electrophilic compounds. These modifications play crucial roles in protein structure, function, and stability. One common modification is the formation of disulfide bonds, which are essential for maintaining the tertiary structure of proteins. Disulfide bonds can be formed through the oxidation of two cysteine residues, creating a strong covalent bond. Another significant modification is the formation of S-glutathionylation, where a glutathione molecule reacts with a cysteine residue, often as a protective mechanism against oxidative stress. Additionally, cysteine can be modified by acetylation, methylation, or nitrosylation, which can influence protein activity and localization. These modifications are tightly regulated and often involve specific enzymes and regulatory mechanisms. Dysregulation of cysteine modifications has been linked to various diseases, including neurodegenerative disorders, cardiovascular diseases, and cancer. Understanding the mechanisms and functions of cysteine modifications is therefore essential for advancing our knowledge of protein biology and developing targeted therapies for related diseases.