Fractionation into Components of a Mixture of Acidic Ninhydrin-Positive Compounds of Mouse Brain Extracts with Thin-Layer and Ion-Exchange Chromatography

Abstract

Abstract A mixture of more than ten acidic or highly ionized ninhydrin-positive compounds of mouse brain extracts, occurring in ion-exchange chromatography from the beginning up to aspartic acid, was analyzed using ion-exchange and thin-layer chromatography standardized with known substances. These formed four peak groups in the chromatogram of an automatic amino acid analyzer. The first group contained cysteic acid, cysteine-sulfinic acid and phosphoserine, which could be separated from each others only by thin-layer chromatography. Only phosphoserine could be identified in the brain extract (about 0.14 mmol/kg brain wet weight), however. Taurine (4.1 mmol/kg) and phosphoethanolamine (1.05 mmol/kg) in the second group could be satisfactorily separated from each others after the hydrolysis of glycerylphosphoethanolamine (about 0.6 mmol/kg) and certain acidic peptides with 6 mol/1 HCl. Hypotaurine (0.03 mmol/kg) and urea (6.6 mmol/kg) were completely overlapped in the third peak, but urea was decomposed in...