title: Purification, crystallization, and preliminary X-ray analysis of PepX, an X-prolyl dipeptidyl aminopeptidase from Lactococcus lactis.
abstract: The X-prolyl dipeptidyl aminopeptidase PepX, a serine peptidase isolated originally from Lactococcus lactis subsp lactis NCDO 763, was cloned and overproduced in Escherichia coli. The enzyme was isolated in its active form in two purification steps. Crystals of PepX were grown by the hanging drop vapor diffusion method using polyethyleneglycol 4000 as precipitant at pH 5.0. The crystals are orthorhombic with cell dimensions a = 92.8 A, b = 102.6 A, and c = 101.6 A, space group P2(1)2(1)2, and probably contain one monomer of 87.5 kDa in the asymmetric unit. The crystals, very stable under X-rays, diffract to at least 2.2 A and are suitable for high-resolution structural analysis.
authors.affiliation: Unité de Biochimie et de Structure des Protéines, INRA, Centre de Recherches de Jouy-en-Josas, France.
authors.forename: J F
authors.initials: JF
authors.lastname: Chich
authors.forename: P
authors.initials: P
authors.lastname: Rigolet
authors.forename: M
authors.initials: M
authors.lastname: Nardi
authors.forename: J C
authors.initials: JC
authors.lastname: Gripon
authors.forename: B
authors.initials: B
authors.lastname: Ribadeau-Dumas
authors.forename: S
authors.initials: S
authors.lastname: Brunie
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D003001:Cloning, Molecular; D003460:Crystallization; D018360:Crystallography, X-Ray; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D004926:Escherichia coli / Q000378:metabolism; D013294:Lactococcus lactis / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D001426:Bacterial Proteins; D011993:Recombinant Fusion Proteins; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; C098392:PepX dipeptidyl aminopeptidase