Characterization of a putative tropinone reductase from Tarenaya hassleriana with a broad substrate specificity

A novel short-chain alcohol dehydrogenase from Tarenaya hassleriana labeled as putative tropinone reductase was heterologously expressed in Escherichia coli. Purified recombinant protein had molecular weight of approximately 30 kDa on 12% sodium dodecyl sulfate-polyacrylamide gel electrophoresis. T. hassleriana tropinone reductase-like enzyme (ThTRL) had not detected oxidative activity. The optimum pH for enzyme activity of ThTRL was weakly acidic (pH 5.0). 50 degrees C was the optimum temperature for ThTRL. The highest catalytic efficiency and substrate affinity for recombinant ThTRL were observed with (+)-camphorquinone (k(cat)/K-m = 814.3 s(-1) mM(-1), K-m = 44.25 mu M). ThTRL exhibited a broad substrate specificity and reduced various carbonyl compounds, including small lipophilic aldehydes and ketones, terpene ketones, and their structural analogs.

Automated summary

The novel enzyme ThTRL from T. hassleriana exhibits broad substrate specificity, able to reduce various compounds with carbonyl groups, and shows high catalytic efficiency under specific conditions.