Which theory is commonly used to model how enzymes interact with their substrates?

• A. Central dogma
• B. Induced fit model
• C. Fluid mosaic model
• D. Lock and key model

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the context of the question. The problem is asking about a theory that explains how enzymes interact with their substrates, which is a fundamental concept in enzymology.
2. Step 2: Review the key theories mentioned in the options: (1) Central dogma, which describes the flow of genetic information (DNA -> RNA -> Protein), and is unrelated to enzyme-substrate interaction. (2) Fluid mosaic model, which explains the structure of cell membranes, also unrelated to enzyme-substrate interaction. (3) Lock and key model, which suggests that enzymes and substrates fit together like a key in a lock, emphasizing specificity. (4) Induced fit model, which proposes that enzymes undergo conformational changes to better fit the substrate upon binding.
3. Step 3: Compare the lock and key model with the induced fit model. The lock and key model assumes a rigid fit, while the induced fit model accounts for flexibility and dynamic changes in enzyme structure, which is more consistent with experimental evidence.
4. Step 4: Recognize that the induced fit model is the commonly accepted theory for enzyme-substrate interaction because it explains how enzymes adapt their shape to bind substrates more effectively, enhancing catalytic activity.
5. Step 5: Conclude that the correct answer is the induced fit model, as it is widely used to describe enzyme-substrate interactions in modern biochemistry.