title: A dynamic light scattering study of beta-galactosidase: environmental effects on protein conformation and enzyme activity.
abstract: Dynamic light scattering (DLS) is a useful technique for analyzing the size, shape, and other structural characteristics of protein molecules in solution. The effects of various environmental conditions on the structure and activity of Aspergillus oryzae beta-galactosidase were studied. DLS was used to determine protein particle size under various salt, pH, and temperature conditions. Changes in the activity and stability of this enzyme caused by different environmental conditions were found to correlate well with the size changes of the protein particles. This change in protein size can be attributed to protein unfolding and aggregation under extreme conditions. The presence of the enzyme substrate, lactose, in the protein solution greatly enhanced enzyme stability by inhibiting aggregation.
authors.affiliation: Department of Chemical Engineering, Ohio State University, Columbus 43210.
authors.forename: S T
authors.initials: ST
authors.lastname: Yang
authors.forename: J L
authors.initials: JL
authors.lastname: Marchio
authors.forename: J W
authors.initials: JW
authors.lastname: Yen
mesh_terms: D001236:Aspergillus oryzae / Q000201:enzymology; D004789:Enzyme Activation; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007785:Lactose / Q000494:pharmacology; D008027:Light; D046911:Macromolecular Substances; D010316:Particle Size; D011189:Potassium Chloride / Q000494:pharmacology; D011487:Protein Conformation; D012542:Scattering, Radiation; D012965:Sodium Chloride / Q000494:pharmacology; D013696:Temperature; D014508:Urea / Q000494:pharmacology; D001616:beta-Galactosidase / Q000737:chemistry* / Q000378:metabolism
chemical_list: D046911:Macromolecular Substances; D012965:Sodium Chloride; D011189:Potassium Chloride; D014508:Urea; D001616:beta-Galactosidase; D007785:Lactose