title: AppA C-terminal plays an important role in its thermostability in Escherichia coli.
abstract: Due to our previous research, mainly the thermostable mutants Q307D, Y311K, and I427L, we conjectured that Escherichia coli AppA phytase's C-terminal plays an important role in its thermostability, and AppA begins to collapse from the C-terminal when at a higher temperature. So here we constructed C-lose mutant to prove it. The residual activities of the wild-type AppA phytase and C-lose were 31.42 and 70.49 %, respectively, after being heated at 80 °C for 10 min. The C-terminal deletion mutant C-lose showed 39.07 % thermostability enhancement than the wild-type both without the pH and temperature optimum changed. It proved the C-lose plays a key role in E. coli AppA phytase's thermostability.
authors.affiliation: Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu, 610064, Sichuan, People's Republic of China. 86silver_z@163.com
authors.forename: Baojin
authors.initials: B
authors.lastname: Fei
authors.forename: Yu
authors.initials: Y
authors.lastname: Cao
authors.forename: Hui
authors.initials: H
authors.lastname: Xu
authors.forename: Xinran
authors.initials: X
authors.lastname: Li
authors.forename: Tao
authors.initials: T
authors.lastname: Song
authors.forename: Zhongan
authors.initials: Z
authors.lastname: Fei
authors.forename: Dairong
authors.initials: D
authors.lastname: Qiao
authors.forename: Yi
authors.initials: Y
authors.lastname: Cao
mesh_terms: D010832:6-Phytase / Q000737:chemistry* / Q000235:genetics*; D000135:Acid Phosphatase / Q000737:chemistry* / Q000235:genetics*; D004795:Enzyme Stability / Q000187:drug effects / Q000528:radiation effects; D004926:Escherichia coli / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D050505:Mutant Proteins / Q000737:chemistry / Q000235:genetics; D055550:Protein Stability / Q000187:drug effects / Q000528:radiation effects
chemical_list: D029968:Escherichia coli Proteins; D050505:Mutant Proteins; D000135:Acid Phosphatase; D010832:6-Phytase; C406788:appA protein, E coli