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Biomedical subjects

Stefan Bienz

Publications and source records attributed to Stefan Bienz.

4 recordsLinked to original sources
PubMed2005

New linear polyamine derivatives in spider venoms.

Linear free polyamines were characterized in the venom of the spiders Agelenopsis aperta, Hololena curta, and Paracoelotes birulai by RP-HPLC coupled to mass spectrometry. The several linear polyamines found were tetramine, pentamine, and hexamine derivatives. Some of these natural products were identified as N-hydroxylated, guanidylated, or acetylated compounds. In addition, the biosynthetical pathway leading to the formation of acylpolyamines in spider venoms is discussed.

Animals↗
PubMed2004

Tandem mass spectrometric investigation of acylpolyamines of spider venoms and their 15N-labeled derivatives.

The fragmentation mechanism of the acylpentamine toxins 1-4 found in the venom of the spider Agelenopsis aperta has been investigated in detail. To identify the origin of the two doublets of unexpected fragment ions at m/z 129/112 and m/z 115/98, three synthetic 15N-labeled analogs 5-7 have been prepared and subjected to CID fragmentation on a triple quadrupole mass spectrometer. It appears that the unexpected doublet of fragment ions arises from an internal portion of the polyamine backbone after either a transaminative Zip reaction or a sequential fragmentation of the quasi-molecular ion. The second option has been proven by in-source CID experiments. The detailed knowledge of acylpentamine fragmentation mechanisms is essential for the correct characterization of isomeric compounds, particularly for coeluting compounds within complex mixtures such as spider venoms.

Animals↗