2-aminoethanesulfonic acid. (Often referred to as an amino acid, but technically is not because it contains a sulfonic acid group, rather than a carboxylic acid, and is not incorporated into proteins.)

Functions and Mechanisms

• Emulsifies lipids (necessary for bile)
• modulates cellular calcium levels
• Synthesis from cysteine - 3 known pathways
  • cysteine Dioxygenase (CDO), an iron-histidine enzyme [is this decarboxylation?]
  • cysteine sulfinic acid decarboxylase (CSAD): decarboxylates
    • cysteine sulfinic acid into hypotaurine
    • cysteic acid into taurine
  • All three pathways require pyridoxal-5'-phosphate (P5P) (the active coenzyme form of vitamin B6) as a cofactor
• Sulfite oxidase (SO), a histidine-molybdenum enzyme, breaks down taurine into sulfate necessary for detoxification
• Synthesized in the liver and the brain; concentrates there and in skeletal muscles, and in the brain.
• Membrane stabilization, osmoregulation, and modulation of cellular calcium levels
• Acylation pathway in Liver Detox Phase II
• present in high concentrations in most tissues, but especially proinflammatory cells

Treats

• Congestive heart failure, cystic fibrosis, toxic exposure, and hepatic disorders.
• Possibly epilepsy and diabetes

Testing:

• Langford (6/05) says insufficient bile (due to a lack of taurine from failure of CDO) is indicated by light-colored stool and elevated copper & mercury. [When I have a liver attack, my stools become paler: more yellow, less brown.] He says supplementing taurine and glycine may help.

Dietary sources:

• Shellfish and organ meats such as liver.
• Milk of other mammals but not cows.

Supplementation - Jo-Mar Labs sells the pure powder; I'm not looking any further.