Fast atom bombardment/tandem mass spectrometry of physalaemin-like peptides

Determination of the primary structure of Paim II, an alpha-amylase inhibitor from Streptomyces coruchorushii, by high-performance tandem mass spectrometry

This study indicates one of the advantages of tandem mass spectrometry; the primary structures of proteins with little structural difference can be determined by using tandem mass spectrometry without prior purification of each component. The primary structure of Paim II, a protein alpha-amylase inhibitor from Streptomyces coruchorushii, was determined by using tandem mass spectrometry. Paim II consists of two component proteins with ragged N-terminus, and was sequenced on the basis of the structure of Paim I, an analogous alpha-amylase inhibitor from the same natural origin.

Recognition, purification, and structural elucidation of mammalian physalaemin-related molecules

Although the PHLIPs are able to enhance gastrointestinal contractility to a very modest extent, the actual physiological significance of the PHLIPs is not completely understood at the present time. Should the high Mr PHLIM be the precursor molecule(s), the PHLIPs may represent partial enzymatic hydrolysis products of the amino-terminal region of the precursor(s). In this regard, it is interesting to note that immunohistochemical staining of rat duodenum indicates the presence of PHY antiserum cross-reacting material in Brunner's glands, which appear to be involved in secretion of mucin. The amphibian peptide, bombesin, has also been detected in amphibian skin mucous glands by immunochemistry; other investigators have indicated that cerulein, an amphibian analog of the carboxy-terminal region of cholecystokinin, is discharged along with mucin from cutaneous glands in Xenopus after the injection of adrenalin.