S-sulphocysteine

S-sulphocysteine is a naturally occurring, endogenous amino acid derivative formed when sulfur metabolism is disrupted, such as in molybdenum cofactor deficiency or sulfite oxidase deficiency. It belongs to the class of organic compounds known as s-conjugated L-cysteines, where the sulfur atom of L-cysteine is substituted with a sulfo group. Structurally, it is a thiosulfate and an analog of glutamate. Mechanistically, S-sulphocysteine acts as a potent agonist at N-methyl-D-aspartate (NMDA) receptors in the central nervous system, leading to increased calcium influx and downstream excitotoxic signaling that can result in neurotoxicity and neuronal damage. Elevated levels are diagnostic markers for certain metabolic disorders affecting sulfur metabolism[5][6]. It has no approved pharmaceutical use but plays an important role as a biomarker and mediator of toxicity in rare genetic diseases.

Other names

L-cysteine S-sulfateS-sulfo-L-cysteinecysteine-S-sulfatecysteine-S-sulfonatecysteinyl-S-sulfonatecysteinyl-S-sulfonic acidS-sulpho-L-cysteinealaninethiosulfuric acid