A class of enzymes that catalyze the removal of water from a substrate molecule, converting an alcohol into an aldehyde or ketone. They play a critical role in a variety of metabolic pathways, including the breakdown of carbohydrates, fatty acids, and amino acids.
While some dehydratases may also have isomerase activity, it's not a defining feature of all dehydratases. Similarly, some isomerases may also have dehydratase activity, but this isn't a defining feature of all isomerases.