Identification of ubiquitin in seminal plasma from Tilapia, oreochromis niloticus

Abstract

The polypeptide ubiquitin, up to now almost exclusively discovered in intracellular spaces, was immunologically detected in Tilapia seminal plasma. Ubiquitin was purified from seminal plasma by column chromatography. N-terminal amino acid sequence analysis revealed 31 N-terminal amino acids to be identical between this ubiquitin and those of several species. Thus, we concluded that the protein detected in seminal plasma is a ubiquitin.