C-Terminal β8-α9 Interaction Modulates Thermal Stability and Enzymatic Activity Differently in Hyperthermophilic Esterase EstE1 and Mesophilic Esterase rPPE.

ABSTRACT: Hydrophobic interactions and hydrogen bonds are 2 types of noncovalent interactions that play distinct roles in the folding and structural stability of proteins. However, the specific roles of these interactions in hydrophobic or hydrophilic environments in α/β-hydrolases are not fully understood. A hyperthermophilic esterase EstE1 in a dimer maintains the C-terminal β8-α9 strand-helix via hydrophobic interactions (Phe276 and Leu299), constituting a closed dimer interface. Moreover, a mesophilic esterase rPPE in a monomer maintains the same strand-helix via a hydrogen bond (Tyr281 and Gln306). Unpaired polar residues (F276Y in EstE1 and Y281A/F and Q306A in rPPE) or reduced hydrophobic interactions (F276A/L299A in EstE1) between the β8-α9 strand-helix decrease thermal stability. EstE1 (F27

SUBMITTER: Nguyen TA 

PROVIDER: S-EPMC10304677 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature