title: The cell-bound proteinase system of Lactobacillus casei--purification and characterization.
abstract: The cell-wall crude extract from Lactobacillus casei NCDO 151 was partially purified by DEAE-Sephacel chromatography. Three active fractions were eluted. Two major peaks (eluted with 0.05 M and 0.27 M phosphate buffer) were further investigated. Peak I represented enzymatic activity with an optimum temperature of 40 degrees C, an optimum pH of 7.0 and was strongly inhibited by the serine proteinase inhibitor phenylmethylsulfonylfluoride. Peak II represented an enzymatic activity with an optimum temperature of 45 degrees C, an optimum pH of 7.5 and was totally inhibited by p-hydroxymercuribenzoate. None of the enzymes was affected by the metal chelator ethylenediaminetetraacetic acid at a concentration up to 1 x 10(-2).
authors.affiliation: Faculty of Agriculture, Alexandria University, Egypt.
authors.forename: N
authors.initials: N
authors.lastname: Ezzat
authors.forename: M
authors.initials: M
authors.lastname: el Soda
authors.forename: H
authors.initials: H
authors.lastname: el Shafei
mesh_terms: D002611:Cheese; D005285:Fermentation; D005516:Food Microbiology; D006863:Hydrogen-Ion Concentration; D007780:Lacticaseibacillus casei / Q000201:enzymology*; D010447:Peptide Hydrolases / Q000302:isolation & purification*; D013696:Temperature
chemical_list: D010447:Peptide Hydrolases