College of Environmental Science and Engineering, Yangzhou University, Yangzhou City, China.
Univ Lyon, INSA De Lyon, CNRS UMR 5240, Lyon, France.
Int J Biol Macromol. 2024 Aug;275(Pt 2):133707. doi: 10.1016/j.ijbiomac.2024.133707. Epub 2024 Jul 6.
Alcohol dehydrogenase (ADH) is an important enzyme that catalyzes alcohol oxidation and/or aldehyde reduction. As one of NAD-dependent ADH types, iron-containing/activated ADH (Fe-ADH) is ubiquitous in Bacteria, Archaea, and Eukaryotes, possessing a similar "tunnel-like" structure that is composed of a domain A in its N-terminus and a domain B in its C-terminus. A conserved "GGGS" sequence in the domain A of Fe-ADH associates with NAD, and one conserved Asp residue and three conserved His residues in the domain B are its catalytic active sites by surrounding with Fe atom, suggesting that it might employ similar catalytic mechanism. Notably, all the biochemically characterized Fe-ADHs from hyperthermophiles that thrive in above 80 °C possess two unique characteristics that are absent in other Fe-ADHs: thermophilicity and thermostability, thereby demonstrating that they can oxidize alcohol and reduce aldehyde at high temperature. Considering these two unique characteristics, Fe-ADHs from hyperthermophiles are potentially industrial biocatalysts for alcohol and aldehyde biotransformation at high temperature. Herein, we reviewed structural and biochemical characteristics of Fe-ADHs from hyperthermophiles, focusing on similarity and difference between Fe-ADHs from hyperthermophiles and their homologs from non-hyperthermophiles, and between hyperthermophilic archaeal Fe-ADHs and bacterial homologs. Furthermore, we proposed future directions of Fe-ADHs from hyperthermophiles.
醇脱氢酶(ADH)是一种重要的酶,能催化醇的氧化和/或醛的还原。作为 NAD 依赖型 ADH 之一,含铁/激活的 ADH(Fe-ADH)在细菌、古菌和真核生物中普遍存在,具有相似的“隧道样”结构,由其 N 端的结构域 A 和 C 端的结构域 B 组成。Fe-ADH 结构域 A 中的保守“GGGS”序列与 NAD 结合,结构域 B 中一个保守的天冬氨酸残基和三个保守的组氨酸残基通过周围的铁原子形成其催化活性位点,表明其可能采用相似的催化机制。值得注意的是,所有在 80°C 以上高温下生长的嗜热菌的生化特性得到表征的 Fe-ADH 都具有两个其他 Fe-ADH 所没有的独特特征:嗜热性和热稳定性,从而表明它们可以在高温下氧化醇和还原醛。鉴于这两个独特的特征,嗜热菌的 Fe-ADH 可能是高温下醇和醛生物转化的潜在工业生物催化剂。本文综述了嗜热菌的 Fe-ADH 的结构和生化特性,重点比较了嗜热菌和非嗜热菌的 Fe-ADH 之间、古菌和细菌的 Fe-ADH 之间的相似性和差异,最后提出了嗜热菌的 Fe-ADH 的未来研究方向。