title: Preparation of bacterial X-prolyl dipeptidyl aminopeptidase and its stabilization by organic cosolvents.
abstract: To obtain large amounts of the X-prolyl dipeptidyl aminopeptidase from Lactococcus lactis subsp lactis (PepX, E.C. 3.4.14.5), PepX was purified from a commercial L. lactis cell extract. The enzyme was purified in only three steps and the last one was performed by HPLC on a C4 reverse-phase column using acetonitrile as an eluent. Despite its high molecular mass (175 kDa), the enzyme was recovered with a good activity yield (75%). Advantages and drawbacks of this technique compared to the classical ones are discussed. The stability of the enzyme in aqueous solutions and in the presence of 10 water-miscible solvents was also investigated. PepX was found to be stabilized by dimethyl sulfoxide, triglyme, and glycerol.
authors.affiliation: Unité Protéines, I.N.R.A., Station de Recherches Laitières, Jouy-en-Josas, France.
authors.forename: J F
authors.initials: JF
authors.lastname: Chich
authors.forename: J C
authors.initials: JC
authors.lastname: Gripon
authors.forename: B
authors.initials: B
authors.lastname: Ribadeau-Dumas
mesh_terms: D000626:Aminopeptidases / Q000737:chemistry / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D004795:Enzyme Stability; D013294:Lactococcus lactis / Q000201:enzymology*; D012997:Solvents
chemical_list: D012997:Solvents; D000626:Aminopeptidases; C022750:X-Pro aminopeptidase