title: Delicate balance of electrostatic interactions and disulfide bridges in thermostability of firefly luciferase.
abstract: The wild type Photinus pyralis luciferase does not have any disulfide bridge. Disulfide bridges are determinant in inherent stability of protein at moderate temperatures. Meanwhile, arginin is responsible for thermostability at higher temperatures. In this study, by concomitant introduction of disulfide bridge and a surface arginin in a mutant (A296C-A326C/I232R), the contribution of disulfide bridge introduction and surface hydrophilic residue on activity and global stability of P. pyralis luciferase is investigated. In addition to the mentioned mutant; I232R, A296C-A326C and wild type luciferases are characterized. Though addition of Arg caused stability against proteolysis but in combination with disulfide bridge resulted in decreased thermal stability compared to A296C-A326C mutant. In spite of long distance of two different mutations (A296C-A326C and I232R) from each other in the three-dimensional structure, combination of their effects on the stability of luciferase was not cumulative.
authors: Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
authors: Somayeh
authors: S
authors: Karimzadeh
authors: Maryam
authors: M
authors: Moradi
authors: Saman
authors: S
authors: Hosseinkhani
mesh_terms: D000178:Acrylamides / Q000494:pharmacology; D000817:Anilino Naphthalenesulfonates / Q000737:chemistry; D004220:Disulfides / Q000737:chemistry*; D004789:Enzyme Activation; D004795:Enzyme Stability / Q000187:drug effects; D007700:Kinetics; D049409:Luciferases, Firefly / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D011193:Potassium Iodide / Q000494:pharmacology; D011487:Protein Conformation; D059748:Proteolysis; D055672:Static Electricity; D013696:Temperature
chemical_list: C515594:8-anilino-1-naphthalenesulfonic acid; D000178:Acrylamides; D000817:Anilino Naphthalenesulfonates; D004220:Disulfides; D011193:Potassium Iodide; D049409:Luciferases, Firefly