苹果酸脱氢酶 (MDH) 由于其在碳代谢以及氧化还原平衡和脂质合成等途径中的关键作用，自 20 世纪 60 年代以来一直受到广泛研究。最近，随着人们发现这些酶在癌症期间发生的代谢变化中的作用，人们对这些酶重新产生了兴趣，并且解决 MDH 研究问题的本科生教学实验室社区——苹果酸脱氢酶 CURE 社区 (MCC) 也广泛存在。本期特刊描述了 MDH 的不同方面，包括其生理作用、结构与功能关系、通过翻译后修饰进行的调节以及对其进化历史的看法。人类有两种同工型：一种是在糖酵解中形成 NAD 的细胞质同工型，另一种是在柠檬酸循环中起主要作用的线粒体同工型。尽管这两种同工型的序列不同，但酶的结构相似，并且研究表明每种同工型可能与共同途径中的其他酶形成复合物。实验和理论的进步有助于表征 MDH 的翻译后修饰，使我们能够提出更复杂的问题，涉及癌症背景下酶和底物混杂的调节。此外，关于苹果酸脱氢酶在其他生物体中的作用，特别是在寄生虫中，还有许多未解决的问题。本期的评论文章旨在阐明我们对 MDH 理解的最新进展，并突出未来研究的领域。© 2024 作者。由波特兰出版社有限公司代表生化学会出版。

Malate dehydrogenases (MDHs) have been extensively studied since the 1960s due to their key roles in carbon metabolism and pathways such as redox balance and lipid synthesis. Recently, there has been renewed interest in these enzymes with the discovery of their role in the metabolic changes that occur during cancer and a widespread community of undergraduate teaching laboratories addressing MDH research questions, the Malate Dehydrogenase CUREs Community (MCC). This special issue describes different facets of MDH, including its physiological role, its structure-function relationships, its regulation through post-translational modifications, and perspectives on its evolutionary history. There are two human isoforms: a cytoplasmic isoform that carries out formation of NAD+ for glycolysis, and a mitochondrial isoform that plays a major role in the citric acid cycle. Although the sequences of these two isoforms vary, the structures of the enzymes are similar, and studies suggest that each isoform may form complexes with other enzymes in common pathways. Experimental and theoretical advances have helped to characterize the post-translational modifications of MDH, allowing us to ask more complex questions involving the regulation of the enzyme and substrate promiscuity in the context of cancer. Additionally, there are many unresolved questions on the role of malate dehydrogenase in other organisms, especially in parasites. The review articles in this issue seek to shed light on the latest advances in our understanding of MDH and highlight areas for future studies.© 2024 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.