Structural and biochemical characterization of Arabidopsis alcohol dehydrogenases reveals distinct functional properties but similar redox sensitivity

• DOI: 10.1111/tpj.16651
• Publication Date: 2024-02-03T04:51:14Z
• Authors: Maria Meloni; Jacopo Rossi; Silvia Fanti; Giacomo Carloni; Daniele Tedesco; Patrick Treffon; Luca Piccinini; Giuseppe Falini; Paolo Trost; Elizabeth Vierling; Francesco Licausi; Beatrice Giuntoli; Francesco Musiani; Simona Fermani; Mirko Zaffagnini
• Keywords: 0301 basic medicine; 0303 health sciences; Arabidopsis thaliana; Ethanol; Arabidopsis Proteins; 3D structure; Arabidopsis thaliana; alcohol dehydrogenase; cysteine; ethanol; nitrosoglutathione; redox sensitivity; thiol oxidation; zinc ion; Alcohol dehydrogenase; alcohol dehydrogenase; thiol oxidation; Arabidopsis; Alcohol Dehydrogenase; 3D structure; Substrate Specificity; zinc ion; redox sensitivity; S-Nitrosoglutathione; ethanol; Amino Acid Sequence; 3D-structure; nitrosoglutathione; cysteine; Oxidation-Reduction

SUMMARY Alcohol dehydrogenases (ADHs) are a group of zinc‐binding enzymes belonging to the medium‐length dehydrogenase/reductase (MDR) protein superfamily. In plants, these fulfill important functions involving reduction toxic aldehydes corresponding alcohols (as well as catalyzing reverse reaction, i.e., alcohol oxidation; ADH1) and nitrosoglutathione (GSNO; ADH2/GSNOR). We investigated compared structural biochemical properties ADH1 GSNOR from Arabidopsis thaliana . expressed purified determined two new structures, NADH‐ADH1 apo‐GSNOR, thus completing landscape ADHs in both apo‐ holo‐forms. A comparison revealed high sequence conservation (59% identity) similar fold. contrast, striking dissimilarity was observed catalytic cavity supporting substrate specificity accommodation. Consistently, showed strict for their substrates (ethanol GSNO, respectively), although had ability oxidize long‐chain alcohols, with performing better than GSNOR. Both contain number cysteines (12 15 out 379 residues GSNOR, respectively) significant responsivity thiol‐oxidizing agents, indicating that redox modifications may constitute mechanism controlling enzyme activity under optimal growth stress conditions.