title: Phosphate buffer effects on thermal stability and H2O2-resistance of horseradish peroxidase.
abstract: Horseradish peroxidase (HRP) has attracted intense research interest due to its potential applications in biotechnological fields. However, inadequate stability under prevalent conditions such as elevated temperatures and H(2)O(2) exposure, has limited its industrial application. In this study, stability of HRP was investigated in the presence of different buffer systems (potassium phosphate and Tris-HCl) and additives. It was shown that the concentration of phosphate buffer severely affects enzyme thermostability in a way that in diluted potassium phosphate buffer (10mM) half-life (from 13 to 35 min at 80 °C) and T(m) (from 73 to 77.5 °C) increased significantly. Among additives tested, trehalose had the most thermostabilizing effect. Exploring the role of glycosylation in stabilizing effect of phosphate buffer, non-glycosylated recombinant HRP was also examined for its thermal and H(2)O(2) stability in both diluted and concentrated phosphate buffers. The recombinant enzyme was more thermally stable in diluted buffer in accordance to glycosylated HRP; but interestingly recombinant HRP showed higher H(2)O(2) tolerance in concentrated buffer.
authors.affiliation: Department of Biotechnology, College of Science, University of Tehran, Tehran, Iran.
authors.forename: Sedigheh
authors.initials: S
authors.lastname: Asad
authors.forename: Seyed-Fakhreddin
authors.initials: SF
authors.lastname: Torabi
authors.forename: Mehrnoosh
authors.initials: M
authors.lastname: Fathi-Roudsari
authors.forename: Nasser
authors.initials: N
authors.lastname: Ghaemi
authors.forename: Khosro
authors.initials: K
authors.lastname: Khajeh
mesh_terms: D002021:Buffers; D002942:Circular Dichroism; D004795:Enzyme Stability; D005453:Fluorescence; D006031:Glycosylation; D006207:Half-Life; D006735:Horseradish Peroxidase / Q000737:chemistry*; D006358:Hot Temperature; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007700:Kinetics; D010710:Phosphates / Q000737:chemistry*; D017680:Potassium Compounds / Q000737:chemistry*; D011994:Recombinant Proteins / Q000737:chemistry*; D014199:Trehalose / Q000737:chemistry
chemical_list: D002021:Buffers; D010710:Phosphates; D017680:Potassium Compounds; D011994:Recombinant Proteins; C013216:potassium phosphate; D014199:Trehalose; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase