Structure Elucidation of a New Icosapeptide from Human Semen

Abstract
Only 300 μg of the new oligopeptide 1 was available for a structure determination. The sequence could be determined by a combination of liquid secondary ion mass spectrometry (LSIMS) and Edman degradation. Crucial for this success was the observation that the sample used for the mass spectrometric analysis could be eluted unchanged from the target and subsequently used for an Edman degradation. equation image