L-ЦИСТАТИОНИН

L-(+)-Cystathionine is a dipeptide formed by serine and homocysteine. Transsulfuration of methionine yields homocysteine, which combines with serine to form this precursor of cysteine. L-(+)-Cystathionine is largely expressed in the mammalian brain and deficiency can indicate the presence of metabolic disorders such as cystathioninuria.

White Crystalline Solid

L-Cystathionine has been used in ultra-performance liquid chromatography for the validation of cystathionine and the correlation of its abundance with vertebrate metamorphosis. It has also been used as an inhibitor of sinusoidal GSH (glutathione) carrier to signify that thiol redox state imbalance is associated with the modulation of autophagy in carcinoma cells.

S,S-Cystathionine is purified by converting it to the HCl salt in 20% HCl and carefully basifying with aqueous NH3 until separation is complete. Filter it off and dry it in a vacuum. It forms prisms from H2O. The dibenzoyl derivative has m 229o (from EtOH). [IR: Greenstein & Winitz Chemistry of the Amino Acids (J Wiley) Vol 3 p2690 1961 and Tallan et al. J Biol Chem 230 707 1958, Synthesis: du Vigneaud et al. J Biol Chem 143 59 1942, Anslow et al. J Biol Chem 166 39 1946.] [Prepn: Weiss & Stekol J Am Chem Soc 73 2497 1951; see also du Vigneaud et al. J Biol Chem 143 60 1942, Biological synthesis: Greenberg Methods Enzymol 5 943 1962, Beilstein 4 IV 3197.]