title: Effects of polyethylene glycol on stability of alpha-chymotrypsin in aqueous ethanol solvent.
abstract: The effects of polyethylene glycol (PEG) of different molecular weights (400, 2000, 6000, 12,000, 20,000, and 35,000) on the conformational stability and catalytic activity of alpha-chymotrypsin in 60% ethanol were studied. The inactivation caused by the organic solvent was not influenced by PEG 400. However, the PEGs with higher molecular weights up to 35,000 increased the stability of the enzyme, but this alpha-chymotrypsin stabilizing effect was molecular weight-independent. With increase of the molecular weight of PEG, a more stable tertiary structure of the enzyme was observed.
authors.affiliation: Department of Biochemistry, Faculty of Science, University of Szeged, Szeged, Hungary. lmsimon@bio.u-szeged.hu
authors.forename: L M
authors.initials: LM
authors.lastname: Simon
authors.forename: M
authors.initials: M
authors.lastname: Kotormán
authors.forename: A
authors.initials: A
authors.lastname: Szabó
authors.forename: G
authors.initials: G
authors.lastname: Garab
authors.forename: I
authors.initials: I
authors.lastname: Laczkó
mesh_terms: D002918:Chymotrypsin / Q000737:chemistry*; D004789:Enzyme Activation; D004795:Enzyme Stability; D000431:Ethanol / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D011092:Polyethylene Glycols / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D012997:Solvents / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D012997:Solvents; D014867:Water; D000431:Ethanol; D011092:Polyethylene Glycols; D002918:Chymotrypsin; C117608:alpha-chymotrypsin