sulfaattion

Sulfatation, more commonly spelled sulfation, is the introduction or transfer of a sulfate group into another molecule. In organic chemistry, sulfation refers to the formation of sulfate esters by reacting an alcohol or phenol with sulfating reagents such as sulfur trioxide, chlorosulfuric acid, or sulfuryl chloride. The resulting product is a sulfate ester (ROSO3H) or its negatively charged form after neutralization (ROSO3−). Sulfation of alcohols or phenols is used to increase solubility, activate a site for further chemical transformation, or introduce a protecting group in synthesis.

In biochemistry, sulfation is a major biological conjugation process that attaches a sulfate group from the donor molecule 3'-phosphoadenosine-5'-phosphosulfate (PAPS) to a wide range of substrates. Enzymes called sulfotransferases catalyze these transfers, modifying hormones, neurotransmitters, drugs, carbohydrates, and proteins. Sulfation often increases hydrophilicity and promotes excretion, while in some cases it modulates biological activity, receptor interactions, or protein function. Tyrosine sulfation, a common post-translational modification of secreted and membrane proteins, influences protein–protein interactions and signaling.

Biological and medical relevance includes its role in drug metabolism, where sulfation competes with other conjugation pathways such as glucuronidation, and where individual variation in sulfotransferase enzymes can affect drug clearance and toxicity. Sulfation also occurs in plants and microbes, contributing to detoxification and the biochemical fate of natural products.