Biochemistry Lecture: Enzymes and Catalysts

What is the compound on which an enzyme acts called?

What is a holoenzyme composed of?

Where does the catalysis occur in an enzyme?

What is the term used for the energy barrier that substrates need to overcome before a reaction will occur?

How do enzymes affect the activation energy required for a reaction?

What happens to the energy barrier required for a reaction when enzymes are present?

Which type of enzymatic action involves breaking a single structure into smaller components or joining two or more substrate molecules together?

What are small organic molecules that act as cofactors for enzymes called?

Which family of enzymes assists in the breakdown of carbohydrates?

What type of specificity describes an enzyme that acts on molecules with specific functional groups such as amino, phosphate, and methyl groups?

Which model explains the enzyme-substrate interaction where the enzyme changes its shape for substrate binding?

What term is used to describe enzymes that contain tightly bound metal ions?

Which type of enzymatic specificity describes an enzyme that acts on a particular steric or optical isomer?

What are tightly bound cofactors called when they perform functions similar to those of prosthetic groups?

Enzymes that require metal ions as loosely bound cofactors are termed as?

What are examples of metal ions that can serve as cofactors for enzymes?

The compound on which an enzyme acts is called a substrate.
A holoenzyme is composed of an enzyme and its cofactor(s), which may be metal ions or organic molecules.
Catalysis in an enzyme occurs at the active site, where substrate binding takes place.

The energy barrier substrates must overcome for a reaction to occur is known as activation energy.
Enzymes lower the activation energy required, facilitating biological reactions by speeding up their rates.
When enzymes are present, the energy barrier for a reaction decreases, enhancing the likelihood of reaction occurrences.

Lyase action breaks a single structure into smaller components, while ligase action joins two or more substrate molecules.
Small organic molecules that act as cofactors for enzymes are referred to as coenzymes.

Amylases are a family of enzymes that assist in the breakdown of carbohydrates.
Group specificity describes enzymes that act on molecules with specific functional groups, such as amino, phosphate, and methyl groups.

The induced fit model explains enzyme-substrate interactions, suggesting that the enzyme alters its shape upon substrate binding.
Enzymes containing tightly bound metal ions are termed metalloenzymes.

Absolute specificity describes enzymes that act on a particular steric or optical isomer.
Tightly bound cofactors performing functions similar to prosthetic groups are called prosthetic groups.
Enzymes requiring metal ions as loosely bound cofactors are known as metal-activated enzymes.