Biomedical subjects
Publications and source records attributed to W Kausler.
A procedure is described to isolate peptides from complex biological fluids (e.g. seminal plasma) in pure form within a short time. The sequence of the isolated peptides was determined by liquid secondary ion mass spectrometry in combination with enzymatic cleavage reactions. The method was used for the structure elucidation of a peptide of molecular weight 2766 u with an N-terminal pyroglutamine residue.
Two previously unknown peptides with a high amount of polar amino acids were isolated from human seminal plasma by a combination of dialysis, gel filtration, ion-exchange chromatography, and RP-HPLC. Their structures were determined by gas-phase sequencing simultaneously considering the different peak intensities.
Practical hints are summarized for the investigation of peptides by soft ionization methods based on liquid secondary ion mass spectrometry. The method aims: to purify the sample; to force a peptide to the surface by ion pair formation; to recover the sample used for mass spectral analysis; to distinguish between Lys and Gln by derivatization; to spot amino acids in the low mass region; and to improve sequence information by use of peptide fragments, not described previously.