Purification and N-terminal sequence of beta-trace, a protein abundant in human cerebrospinal fluid.

beta-Trace, a protein that represents a major constituent of human cerebrospinal fluid with unknown function has been purified to apparent homogeneity by gel chromatography and electrophoresis. After sodium dodecylsulfate electrophoresis on polyacrylamide gels (SDS-PAGE) and Western blotting, the N-terminal sequence (28 amino acids) has been determined. The high degree of identity with the corresponding sequences of prostaglandin D synthetase from rat (68%) and human (93%) suggests a strong relationship if not identity with this enzyme. Thus, 30 years after its discovery beta-trace might unravel as a well-known protein of the prostaglandin metabolism.