No abstract

Advanced organic polymer electrode based on PTVE-functionalized carbon nanotubes is prepared for sodium organic battery.

The thermostable esterase Est-Y29, belonging to the family VIII lipolytic esterase isolated 20 from metagenomes extracted from the topsoil in Republic of Korea, was identified as a 21 promising catalyst for the production of (S)-ketoprofen, an important nonsteroidal anti-22 inflammatory drug (NSAID). For industrial applications, the enantioselectivity of the enzyme towards the S-enantiomer of the racemic ketoprofen ester substrate needs to be improved. To 24 understand the structural basis of Est-Y29 enantioselectivity, which is necessary for the rational 25 design of an enzyme with enhanced enantioselectivity, we solved the crystal structures of Est-26 Y29 bound to (S)-ketoprofen at 1.69 Å resolution. Structural analyses revealed that the S-27 enantiomer can be stabilized by a -interaction between the methyl substituent at the chiral 28 carbon of the ligand and the aromatic pocket formed by Tyr123, Phe125, and Tyr170. This 29 finding is further supported by the highly improved enantioselectivity of the mutant Est-Y29 30 (F125W) toward (S)-ketoprofen due to the enhanced -interaction. Our results provide the 31 molecular basis of the enantioselectivity of Est-Y29 against (S)-ketoprofen and further offer 32 the opportunity for the rational design of enzyme enantioselectivity as well as potential 33 applications of the mutant Est-Y29 to industrial biocatalysts.