Hydrolase vs. Hydratase — What's the Difference?

Hydrolases are a broad class of enzymes that catalyze the hydrolysis of various chemical bonds, including ester, glycosidic, peptide, and other bonds, using water. This process often results in the breakdown of complex molecules into simpler ones, facilitating various biological functions such as digestion and metabolism. On the other hand, hydratases, also known as hydro-lyases, specifically catalyze the addition of water to double bonds in a substrate without breaking the substrate into two parts. This action typically involves the conversion of one molecule into another, often playing a crucial role in metabolic pathways like the citric acid cycle.

Hydrolases are involved in critical biological processes across all forms of life, from bacteria to humans, showcasing their versatility in biochemistry. They are essential for recycling cellular components, degrading food into absorbable nutrients, and regulating biomolecules. Whereas hydratases have a more specialized function, mainly involved in specific metabolic pathways, such as the hydration of fumarate to malate in the citric acid cycle or the conversion of 2-acetyl-CoA to acetoacetyl-CoA in fatty acid synthesis, indicating their specialized roles in metabolism.

The activity of hydrolases is fundamental in various industrial and biotechnological applications, including waste treatment, the food industry, and pharmaceuticals, where they are used to synthesize or degrade complex biomolecules. Hydratases, while less widely applied industrially, are crucial in the synthesis of certain pharmaceuticals and chemicals, illustrating their importance in both natural and engineered chemical processes.

Hydrolases can be highly specific to their substrates or exhibit broad specificity, allowing them to act on a wide range of substrates. This diversity makes them indispensable in biological systems for maintaining cellular homeostasis. In contrast, hydratases typically exhibit high specificity towards their substrates, catalyzing hydration reactions in particular substrates within specific metabolic pathways, reflecting their tailored roles in cellular processes.

Understanding the mechanisms and functions of hydrolases and hydratases is vital for advancements in biochemistry and molecular biology. The study of hydrolases has led to significant developments in drug design and the treatment of diseases where these enzymes are involved. Meanwhile, hydratases are studied for their role in metabolic engineering and synthetic biology, aiming to produce novel compounds or improve metabolic efficiencies.