期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1978
卷号：75
期号：9
页码：4115-4119
DOI：10.1073/pnas.75.9.4115
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The presence or absence of peptide hormones in tissue extracts may in certain cases be demonstrated by exposing the extracts to conditions under which characteristic fragments of the polypeptide molecule in question are formed and then analyzing for such fragments. An approximate quantitation of the hormones may also be achieved thereby. In the present work the COOH-terminal fragments of polypeptides containing characteristic alpha-amide groups were released enzymatically and then converted into the fluorescent dansyl derivatives, which were identified by thin-layer chromatography. In this way the presence of secretin, cholecystokinin, and the vasoactive intestinal peptide in concentrates of porcine intestinal extracts were demonstrated by their COOH-terminal amide fragments: valine (or leucylvaline) amide, phenylalanine amide, and asparagine (or leucylasparagine) amide, respectively. The analytical methodology used in the present study may also be useful in devising simple and reliable chemical assay methods for the isolation of already known polypeptides and in the isolation of previously uncharacterized polypeptides from natural sources.
