title: Introducing a salt bridge into the lipase of Stenotrophomonas maltophilia results in a very large increase in thermal stability.
abstract: High thermostability of enzymes is a prerequisite for their biotechnological applications. An organic solvent-tolerant and cold-active lipase, from the Stenotrophomonas maltophilia, was unstable above 40 °C in previous studies. To increase the enzyme stability, possible hydrogen-bond networks were simulated by the introduction of a salt bridge in a highly flexible region of the protein. Compared with the wild-type lipase, a mutant lipase (G165D and F73R) showed a >900-fold improvement in half-life at 50 °C, with the optimal activity-temperature increasing from 35 to 90 °C. Therefore, the hydrogen-bond strategy is a powerful approach for improving enzyme stability through the introduction of a salt bridge.
authors.affiliation: Institute of Bioengineering, Department of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, People's Republic of China.
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Wu
authors.forename: Mu
authors.initials: M
authors.lastname: Li
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhou
authors.forename: Li-Rong
authors.initials: LR
authors.lastname: Yang
authors.forename: Gang
authors.initials: G
authors.lastname: Xu
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D004795:Enzyme Stability / Q000235:genetics; D006358:Hot Temperature; D006860:Hydrogen Bonding; D008049:Lipase / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D056004:Molecular Dynamics Simulation; D016297:Mutagenesis, Site-Directed; D011487:Protein Conformation; D020615:Stenotrophomonas maltophilia / Q000201:enzymology* / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D008049:Lipase