The Characterization of Ancient Methanococcales Malate Dehydrogenases Reveals That Strong Thermal Stability Prevents Unfolding Under Intense γ-Irradiation.

ABSTRACT: Malate dehydrogenases (MalDHs) (EC.1.1.1.37), which are involved in the conversion of oxaloacetate to pyruvate in the tricarboxylic acid cycle, are a relevant model for the study of enzyme evolution and adaptation. Likewise, a recent study showed that Methanococcales, a major lineage of Archaea, is a good model to study the molecular processes of proteome thermoadaptation in prokaryotes. Here, we use ancestral sequence reconstruction and paleoenzymology to characterize both ancient and extant MalDHs. We observe a good correlation between inferred optimal growth temperatures and experimental optimal temperatures for activity (A-Topt). In particular, we show that the MalDH present in the ancestor of Methanococcales was hyperthermostable and had an A-Topt of 80 °C, consistent with a hyperther

SUBMITTER: Madern D 

PROVIDER: S-EPMC11631191 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature