title: Purification and partial characterization of aminopeptidase from barley (Hordeum vulgare L.) seeds.
abstract: Aminopeptidases (EC 3.4.11) are proteolytic enzymes, which hydrolyze one amino acid from N-terminus of peptidic substrates. Inhibitors of plant aminopeptidases can find an application in agriculture as herbicides. Isolation and partial characterization of aminopeptidase from barley (Hordeum vulgare L.) seeds has been described. The enzyme was purified to molecular homogeneity using a six-step purification procedure (precipitation with (NH4)2SO4, followed by chromatography on Sephadex G-25, DEAE-Sepharose, Sephacryl HR 300, Macro-Prep Q and Phenyl-Sepharose HP columns). The enzyme was purified 365-fold with recovery above 18%. The molecular weight of the purified enzyme was determined by SDS-PAGE and gel filtration as 58 kDa, and was found to be a monomer. Its pH and temperature optima were 7.5 and 52 °C, respectively. The enzyme behaves as standard leucine aminopeptidase by preferring bulky amino acids at the N-terminus, with phenylalanine being of choice.
authors: Faculty of Chemistry, University of Opole, Oleska 48, 45-052 Opole, Poland. bartosz.oszywa@pwr.wroc.pl
authors: Bartosz
authors: B
authors: Oszywa
authors: Maciej
authors: M
authors: Makowski
authors: Małgorzata
authors: M
authors: Pawełczak
mesh_terms: D000626:Aminopeptidases / Q000302:isolation & purification* / Q000378:metabolism*; D001467:Hordeum / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D010940:Plant Proteins / Q000302:isolation & purification / Q000378:metabolism; D012639:Seeds / Q000201:enzymology*; D013696:Temperature
chemical_list: D010940:Plant Proteins; D000626:Aminopeptidases