2.5 Enzymes Flashcards
What are enzymes?
Biological catalysts that speed up the rate of a reaction by lowering activation energy required
Are enzymes globular or fibrous?
They are globular proteins
Do enzymes get destroyed in the reaction?
No. They are not changed or consumed by reactions they catalyze. They can be reused.
What is a substrate?
Molecule acted on by the enzyme
How do you recognize an enzyme?
Usually end with -ase and named after molecules they react with.
What is the active site?
Region/indentation on surface of enzyme that binds to the substrate molecule
What is responsible for catalytic activity of enzyme?
Sequence of amino acids
How are active sites specific to substrate?
They complement in terms of shape and chemical properties.
Why are some enzymes fixed in position? eg. in membrane
To localize certain reactions to a particular site
Enzyme-substrate complex
When substrate binds to active site
Enzyme-product complex
Formed when enzyme catalyzes conversion of substrate into product
What is collision frequency?
Rate of enzyme catalysis
2 ways to increase collision frequency
- Increase molecular motion using thermal energy
- Increase concentration of particles (either substrate or enzyme)
What type of structure does enzyme specificity depend on?
Tertiary structure
