Structural and biochemical insights into the thermostable esterase Ta0887 from Thermoplasma acidophilum.

Authors

Alejandro Delgado-Rey, Miriam Livier Llamas-García, Gabriela M Montero-Morán, Leticia Santos, Samuel Lara-González

Published in

FEBS open bio. Aug 21, 2026. Epub Aug 21, 2026.

Abstract

Microbial esterases are versatile and stable enzymes with a wide range of biotechnological applications. However, few esterases have been characterized from archaea, an important source of extremophilic enzymes. In this study, we report the biochemical characterization and crystal structure of Ta0887, a novel esterase from the thermoacidophilic archaeon Thermoplasma acidophilum. The protein was successfully cloned, expressed, and purified in Escherichia coli. Light scattering assays revealed that Ta0887 is a monomer in solution. Activity assays using p-nitrophenyl (p-NP) esters confirmed its esterase activity, showing a substrate preference for p-NP hexanoate (C6). Furthermore, the substitution of Ser95 with alanine completely abolished enzymatic activity, thereby confirming its essential role as the nucleophilic residue of the catalytic triad. The enzyme exhibited optimal activity at 65 °C and pH 8.0. Notably, Ta0887 displayed high thermal stability, retaining 66% residual activity after incubation at 80 °C for 2 h, consistent with its thermal denaturation midpoint temperature of 80.6 °C. The crystal structure of Ta0887, resolved at 1.93 Å, revealed an α/β-hydrolase core domain consisting of an eight-strand β-sheet, surrounded by seven α-helices, and a cap domain comprising four α-helices. Ta0887 features a large substrate-binding pocket at the interface between the two domains that contains the conserved residues Ser95, Asp187, and His215 of the catalytic triad. Further analysis indicates that an efficiently packed hydrophobic core is a key feature for the observed thermostability. The findings from this study provide a basis for the future engineering of Ta0887 with the aim of enhancing its potential for industrial and biotechnological applications.

PMID:
42630012
Bibliographic data and abstract were imported from PubMed on 22 Aug 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.