title: Crystallization of beta-galactosidase does not reduce the range of activity of individual molecules.
abstract: By use of a capillary electrophoresis-based procedure, it is possible to measure the activity of individual molecules of beta-galactosidase. Molecules from the crystallized enzyme as well as the original enzyme preparation used to grow the crystals both displayed a range of activity of 20-fold or greater. beta-Galactosidase molecules obtained from two different crystals had indistinguishable activity distributions of 31,600 +/- 1100 and 31,800 +/- 1100 reactions min(-1) (enzyme molecule)(-1). This activity was found to be significantly different from that of the enzyme used to grow the crystals, which showed an activity distribution of 38,500 +/- 900 reactions min(-1) (enzyme molecule)(-1).
authors.affiliation: Chemistry Department, University of Winnipeg, Winnipeg, Manitoba, R3B 2E9, Canada.
authors.forename: Glen K
authors.initials: GK
authors.lastname: Shoemaker
authors.forename: Douglas H
authors.initials: DH
authors.lastname: Juers
authors.forename: Jennifer M L
authors.initials: JM
authors.lastname: Coombs
authors.forename: Brian W
authors.initials: BW
authors.lastname: Matthews
authors.forename: Douglas B
authors.initials: DB
authors.lastname: Craig
mesh_terms: D003460:Crystallization; D019075:Electrophoresis, Capillary / Q000379:methods / Q000592:standards; D004789:Enzyme Activation; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000302:isolation & purification* / Q000592:standards; D005456:Fluorescent Dyes / Q000592:standards; D005697:Galactosides / Q000592:standards; D010078:Oxazines / Q000592:standards; D013379:Substrate Specificity; D001616:beta-Galactosidase / Q000737:chemistry* / Q000302:isolation & purification* / Q000592:standards
chemical_list: D029968:Escherichia coli Proteins; D005456:Fluorescent Dyes; D005697:Galactosides; D010078:Oxazines; C014180:resorufin; C056561:resorufin galactopyranoside; D001616:beta-Galactosidase