1. Aldehyde-alcohol dehydrogenase undergoes structural transition to form extended spirosomes for substrate channeling.
- Author
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Kim G, Yang J, Jang J, Choi JS, Roe AJ, Byron O, Seok C, and Song JJ
- Subjects
- Crystallography, X-Ray, Escherichia coli genetics, Models, Molecular, Protein Conformation, Substrate Specificity, Alcohol Dehydrogenase chemistry, Alcohol Dehydrogenase metabolism, Aldehyde Oxidoreductases chemistry, Aldehyde Oxidoreductases metabolism, Aldehydes metabolism, Cryoelectron Microscopy methods, Escherichia coli enzymology, Escherichia coli Proteins chemistry, Escherichia coli Proteins metabolism, Ethanol metabolism, Organelles metabolism
- Abstract
Aldehyde-alcohol dehydrogenase (AdhE) is an enzyme responsible for converting acetyl-CoA to ethanol via acetaldehyde using NADH. AdhE is composed of two catalytic domains of aldehyde dehydrogenase (ALDH) and alcohol dehydrogenase (ADH), and forms a spirosome architecture critical for AdhE activity. Here, we present the atomic resolution (3.43โÅ) cryo-EM structure of AdhE spirosomes in an extended conformation. The cryo-EM structure shows that AdhE spirosomes undergo a structural transition from compact to extended forms, which may result from cofactor binding. This transition leads to access to a substrate channel between ALDH and ADH active sites. Furthermore, prevention of this structural transition by crosslinking hampers the activity of AdhE, suggesting that the structural transition is important for AdhE activity. This work provides a mechanistic understanding of the regulation mechanisms of AdhE activity via structural transition, and a platform to modulate AdhE activity for developing antibiotics and for facilitating biofuel production.
- Published
- 2020
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