Enzymatic maturation of pro-opiomelanocortin by anterior pituitary granules. Methodological approach leading to definite characterization of cleavage sites by means of high-performance liquid chromatography and microsequencing.
The coupling of high-performance liquid chromatography, gel-permeation, and reversed-phase chromatography with microsequencing proved to be advantageous for the unambiguous determination of specific sites in pro-opiomelanocortin, cleaved by secretory granule lysates of pig anterior pituitary. This system allows the unambiguous identification of a major chymotrypsin-like enzyme activity, optimal at pH 8.0, in the granule preparation, with a specificity directed towards some Phe decreases X and Tyr decreases X cleavage sites. The approach used emphasizes the necessity to use methodologies leading to the unambiguous determination of conversion activities.
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002458:Cell Fractionation; D002851:Chromatography, High Pressure Liquid; D003594:Cytoplasmic Granules / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D010455:Peptides / Q000032:analysis; D010903:Pituitary Gland, Anterior / Q000378:metabolism*; D010908:Pituitary Hormones, Anterior / Q000378:metabolism*; D011333:Pro-Opiomelanocortin; D011498:Protein Precursors / Q000378:metabolism*; D051381:Rats; D013552:Swine
D010455:Peptides; D010908:Pituitary Hormones, Anterior; D011498:Protein Precursors; D011333:Pro-Opiomelanocortin