This model represents a family of malate dehydrogenases in bacteria and eukaryotes which utilize either NAD or NADP depending on the species and context. MDH interconverts malate and oxaloacetate and is a part of the citric acid cycle as well as the C4 cycle in certain photosynthetic organisms.
Jiyao W et al.(2023). "The conserved domain database in 2023.",