ISSN:
1471-4159
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Abstract: An adrenomedullary protease capable of generating Met5-enkephalin from endogenous precursor(s) has been purified 1,000-fold using affinity chromatog-raphy in combination with gel filtration. This trypsin-like enzyme has an apparent molecular weight of 20,000 dal-tons by gel filtration. The reactivity of the enzyme toward several fluorogenic peptides, Peptides E and F, and the heptapeptides, Met5-enkephalin-Arg6-Phe7 and Met5-en-kephalin-Arg6-Arg7, was examined. The two heptapeptides and the fluorogenic compounds were poor substrates for the adrenal enzyme; in contrast, Peptides E and F were cleaved. The low molecular weight products of Peptide F digestion were identified by HPLC as Arg1-Met6-enkephalin, Met5-enkephalin, and Met5-enkephalin-Lys6, while digestion of Peptide E resulted in the production of Leu5-enkephalin and Met5-enkephalin-Arg6-Arg7. [3H]-βm-Lipotropin was not hydrolyzed by the adrenal enzyme. These results indicate that this adrenomedullary protease is capable of cleaving adrenal opioid peptides at the paired basic sites and thus represents a possible candidate for a proenkephalin-converting enzyme.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1471-4159.1984.tb02802.x
