Mode of action of enzyme | lock and key model | induced fit model

Summary

This video explains two models of enzyme action: the Lock and Key model and the Induced Fit model. The Lock and Key model, proposed by Emil Fischer, suggests that substrates bind specifically to an enzyme's active site, similar to a key fitting into a lock. In contrast, the Induced Fit model, introduced by Daniel Koshland, suggests that the enzyme's active site initially doesn't match the substrate but changes shape upon binding, much like a hand fitting into a glove. Both models emphasize enzyme specificity and adaptability in catalyzing reactions.

Takeaways

• 😀 The Lock and Key model was proposed by Emil Fischer to explain enzyme-substrate interaction.
• 😀 According to the Lock and Key model, the enzyme's active site is specifically complementary to the substrate.
• 😀 In the Lock and Key model, the substrate binds to the enzyme, is converted into a product, and then released.
• 😀 The Lock and Key model is analogous to a key fitting into a lock, where specificity is critical.
• 😀 The Induced Fit model was proposed by Daniel Koshland and emphasizes the dynamic nature of enzyme-substrate interaction.
• 😀 In the Induced Fit model, the enzyme's active site is not initially complementary to the substrate.
• 😀 The active site of the enzyme changes its shape after the substrate approaches, allowing for proper binding.
• 😀 The Induced Fit model is compared to a hand fitting into a glove, where the glove adjusts to the hand's shape.
• 😀 The Induced Fit model focuses on the flexibility of the enzyme's active site, unlike the rigid Lock and Key model.
• 😀 Both models explain the specificity and mechanism by which enzymes catalyze reactions, but from different perspectives.

Q & A

What is the lock and key model of enzyme action?

The lock and key model, proposed by Emil Fischer, suggests that the substrate is specific to the enzyme's active site, much like a key fitting into a lock. The substrate binds to the active site, and the enzyme then converts it into a product.

Who proposed the lock and key model?

The lock and key model was proposed by Emil Fischer.

What happens to the substrate in the lock and key model?

In the lock and key model, the substrate binds specifically to the enzyme's active site and is then converted into the product.

How does the lock and key model compare to the real-world analogy of a lock and key?

In the lock and key model, the enzyme's active site is like a lock, and the substrate is like a key that only fits that specific lock, meaning only certain substrates can interact with a particular enzyme.

What is the induced fit model of enzyme action?

The induced fit model, proposed by Daniel Koshland, suggests that the enzyme's active site is initially not complementary to the substrate. When the substrate approaches, the enzyme changes its shape to fit the substrate, enabling it to convert the substrate into a product.

Who proposed the induced fit model?

The induced fit model was proposed by Daniel Koshland.

How does the induced fit model differ from the lock and key model?

The induced fit model differs from the lock and key model in that the enzyme's active site is not initially complementary to the substrate. It only changes its shape when the substrate binds, unlike the lock and key model where the enzyme's active site and substrate are already complementary.

What is a real-world analogy used to describe the induced fit model?

The induced fit model is often compared to hands fitting into gloves. Just as a hand adjusts the shape of a glove to fit its size and shape, the enzyme's active site changes shape to accommodate the substrate.

What happens to the enzyme's active site in the induced fit model?

In the induced fit model, the enzyme's active site changes shape after the substrate approaches, ensuring a better fit for the substrate to be converted into a product.

How do both the lock and key model and the induced fit model explain enzyme-substrate interaction?

Both models explain how enzymes interact with substrates to produce products, but they differ in how the enzyme's active site relates to the substrate. In the lock and key model, the enzyme's active site is already a perfect fit for the substrate, while in the induced fit model, the enzyme's active site adjusts to fit the substrate.