The enzyme catalysting breakdown without addition of water are called

Options

A. Lyases
B. Hydrolases
C. Ligases
D. Oxidoreductases.

Answer

To answer the question, "The enzyme catalyzing breakdown without addition of water are called," we can follow these steps:

### Step 1: Understand the Types of Enzymes
Enzymes can be classified based on their functions. Some enzymes require water to catalyze reactions, while others do not.

### Step 2: Identify Enzymes that Use Water
Enzymes that catalyze the breakdown of substrates with the addition of water are known as hydrolases. Examples include digestive enzymes like sucrase and lactase, which break down disaccharides into monosaccharides.

### Step 3: Identify Enzymes that Do Not Use Water
The enzymes that catalyze the breakdown of substrates without the addition of water are called lyases. Lyases facilitate the cleavage of bonds by removing groups without hydrolysis.

### Step 4: Provide an Example of a Lyase
An example of a lyase is aldolase, which catalyzes the breakdown of fructose 1,6-bisphosphate into dihydroxyacetone phosphate and phosphoglyceraldehyde during glycolysis. This reaction involves splitting a 6-carbon molecule into two 3-carbon molecules.

### Step 5: Differentiate from Other Enzymes
It is important to note that ligases are enzymes that synthesize molecules by joining two groups together, and oxidoreductases are involved in oxidation-reduction reactions. These are not relevant to the question at hand.

### Conclusion
Thus, the correct answer to the question is that the enzyme catalyzing breakdown without the addition of water is called a **lyase**.

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