2aminoethanesulfonic

2-aminoethanesulfonic acid, commonly known as taurine, is an organic compound classified as an amino sulfonic acid. Its chemical formula is C2H7NO3S and its molecular weight is about 125.15 g/mol. At physiological pH it largely exists as a zwitterion, with a protonated amino group and a deprotonated sulfonate group.

Taurine occurs widely in animal tissues and is especially abundant in bile, where it conjugates with bile acids to form taurocholic and other taurine-conjugated bile acids. It is also present in many foods of animal origin. In mammals, taurine is synthesized endogenously from cysteine via the pathway that involves cysteine sulfinic acid decarboxylase, producing hypotaurine which is subsequently oxidized to taurine; this synthesis is limited in cats, making dietary taurine essential for feline health. The process requires vitamin B6 as a cofactor.

Biological roles of taurine include osmoregulation, antioxidation, membrane stabilization, calcium signaling, and neuromodulation. It contributes to the conjugation of bile acids, supports cellular water balance, and is implicated in neuroprotective and cytoprotective effects in various tissues.

Taurine is widely used as a dietary supplement and is a common ingredient in some energy drinks, infant formulas, pharmaceuticals, and cosmetics. It is naturally present in meat, fish, and dairy products, and it is a key additive in cat and certain other pet foods due to feline dietary requirements.

Safety and regulation are generally favorable; taurine has a high safety margin at typical dietary intakes. As with any supplement, high-dose use should follow applicable guidelines and consider potential interactions with other substances.