Open AccessIsolation of a dipeptidyl aminopeptidase, a putative processing enzyme, from skin secretion of Xenopus laevis
Author(s) -
MOLLAY Christa,
VILAS Ulrike,
HUTTICHER Anton,
KREIL Günther
Publication year - 1986
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1986.tb09935.x
Subject(s) - xenopus , aminopeptidase , enzyme , dipeptidyl peptidase , biochemistry , oligopeptide , alanine , amino acid , chemistry , proline , secretion , hydrolysis , peptide sequence , cleavage (geology) , stereochemistry , biology , peptide , leucine , gene , paleontology , fracture (geology)
A dipeptidyl aminopeptidase has been purified to apparent homogeneity from skin secretion of Xenopus laevis. This enzyme is a glycoprotein with a molecular mass of about 98 kDa. It hydrolyzes a variety of dipeptidyl‐ p ‐nitroanilides and oligopeptides containing proline, alanine or glycine as the second amino acid and is inhibited by diisopropylfluorophosphate. The pH optimum was found to be around 8, while at pH 6, substrates were cleaved at about one‐third of the maximal rate. This dipeptidyl aminopeptidase has the specificity required for the cleavage of amino‐terminal extensions preceding the sequence of caerulein and xenopsin in their respective precursors.