Expression and characterization of Est2: a novel cold-adapted esterase from Antarctic bacterium defining the new esterase family XXII.

ABSTRACT: Extremozymes from Antarctic microbiota represent a potential source of unique biocatalysts. In this study, a novel esterase gene est2 was identified from the Antarctic bacterium Pseudomonas sp. A6-5. Phylogenetic and sequence analyses classified it as the founding member of a new esterase family XXII. The catalytic triad of the enzyme consisted of Ser¹⁴¹, Asp²⁷⁵, and His³⁰³, with the nucleophilic Ser¹⁴¹ situated within the characteristic GXSXG motif of α/β-hydrolases. Est2 exhibited remarkable cold-adaptation where 20-85% of the maximum activity was observed at temperatures ranging from 0 to 15°C. Substrate specificity profiling revealed preferential hydrolysis of medium-chain p-nitrophenyl esters and triglyceride emulsions.

SUBMITTER: He Y 

PROVIDER: S-EPMC12446244 | biostudies-literature | 2025

REPOSITORIES: biostudies-literature