Purification and properties of glutamyl aminopeptidase from chicken egg-white.
Hydrolytic activities characteristic for different aminopeptidases were detected in the egg-white of unfertilized chicken eggs, and one aminopeptidase was isolated in an electrophoretically homogeneous form. The isolated aminopeptidase preferentially hydrolyzed bonds of alpha-glutamyl residue at the NH(2)-end of synthetic substrates and peptides. The enzyme is a dimer with an M(r) of 320,000 and pI of 4.2. Its optimal pH and temperature are 7.6 and 60 degrees C, respectively. EDTA, amastatin, and N-bromosuccinimide are inhibitors, while Ca2++ and Mn2+ are activators of the enzyme Ca2+ also stabilizes the enzyme. According to the observed properties, the isolated chicken egg-white aminopeptidase belongs to the glutamyl aminopeptidases.
Petrović
S
S
Department of Organic Chemistry and Biochemistry, "Rudjer Bosković" Institute, Zagreb, Yugoslavia.
Vitale
L
L
D000626:Aminopeptidases / Q000302:isolation & purification* / Q000378:metabolism; D000818:Animals; D002384:Catalysis; D002645:Chickens / Q000378:metabolism*; D004529:Egg White / Q000032:analysis*; D004795:Enzyme Stability; D043384:Glutamyl Aminopeptidase; D008970:Molecular Weight; D013379:Substrate Specificity
D000626:Aminopeptidases; D043384:Glutamyl Aminopeptidase