biothiols

Biothiols are a class of organic compounds containing a thiol group (-SH) attached to a biological molecule. Thiols, also known as mercaptans, are characterized by the presence of a sulfur atom bonded to a hydrogen atom. In biological systems, these sulfur-containing functional groups play crucial roles in a wide variety of processes.

The most well-known biothiol is cysteine, an amino acid essential for protein structure and function. The thiol group of cysteine residues can form disulfide bonds (-S-S-) with other cysteine residues, which are vital for stabilizing the three-dimensional folding of proteins. This disulfide bond formation is a reversible process that can be influenced by the cellular redox environment.

Beyond cysteine, other important biothiols include glutathione, a tripeptide that acts as a major antioxidant in cells. Glutathione protects cells from oxidative damage by scavenging reactive oxygen species and also plays a role in detoxification and the regulation of cellular signaling pathways. Thiols are also found in coenzymes like coenzyme A, which is central to metabolism, and in various signaling molecules. The reactivity of the thiol group makes biothiols potent nucleophiles and reducing agents, contributing to their diverse biological functions. Their presence and activity are essential for maintaining cellular health and integrity.