Genomic prospecting and biochemical characterization of a novel thermostable 3-quinuclidinone reductase from hot spring metagenomes for efficient biocatalysis.

A novel thermophilic 3-quinuclidinone reductase (ScQR) from hot spring metagenomes retains 86% activity after 48 hours at 70°C, making it highly heat-stable.

• Why it matters: High thermal stability is crucial for industrial biocatalysts, yet few enzymes from extreme environments have been characterized for this trait, limiting their application potential.
• What they did: Metagenomic mining identified ScQR, which was heterologously expressed in Escherichia coli, and its catalytic properties, structural features, and stability were systematically analyzed, including enzyme assays, structural modeling, molecular dynamics, and computational design of variants.
• The result: ScQR's exceptional thermal stability and stereoselectivity for ( R )-3-quinuclidinol, along with improved variants, suggest its promise as a biocatalyst for high-temperature pharmaceutical and biotechnological processes.