Enzymes Flashcards
What are Enzymes
Enzymes are tertiary structure protein based biological catalysts that help in completing functions within organisms. Enzymes have the ability to speed up the rate of reaction within an organism while remaining unchanged. Enzymes are responsible for 2 types of reactions Catabolic (breaking bonds) and Anabolic (forming bonds).
What are some of the features of enzymes
Found in all living things
Used in Metabolic processes
Globular Proteins
May have a prosthetic group in the center
Have an active site
Lowers activation energy of chemical reactions
Are very specific in nature
Are reusable
Only a small amount required for reactions
Sensitive to pH, Temp and substrate concentration
Rate of reaction can be inhibited
Some enzymes need cofactors and coenzymes
What are substrates
Substrates are the molecule upon which enzymes may act. The substrate enters the active site to begin the reaction and forms temporary bonds with the R group of the amino acid in the enzyme. The enzyme converts the substrate into different molecules known as products.
What is the active site
The active site is the region of an enzyme where substrate molecules bind and undergo a chemical reaction. It contains amino acids which form temporary bonds with the substrate. The active site can either be highly specific to the substrate(Lock and Key mechanism) or Adapted to the substrate (Induced fit mechanism). The substrate can be blocked from reaching the active site through a process known as inhibition.
What are the Induced Fit and Lock and Key mechanisms
The Lock and key mechanism is where the shape of the active site matches the shape of the substrate molecule. The induced fit mechanism says the active site molds itself around the substrate to create a tighter fit for the substrate and allow for faster reactions.
What is Enzyme inhibition
Enzyme inhibition is when an inhibitor slows down or stops enzyme controlled reactions. There are 2 types of Inhibition Competitive and Non Competitive both of these can either be Reversible or Irreversible.
Competitive Inhibition- Inhibitors compete with the substrate to bind with the active site
Non Competitive Inhibition- Inhibitors bind to the allosteric site resulting in decreased efficacy on the enzyme.
What is activation energy and how do enzymes affect it
The activation energy is the energy needed to begin a reaction. Enzymes help in lowering the activation energy. The lower the activation energy the faster the rate of reaction.
What are Coenzymes and Cofactors
Coenzymes and Cofactors are enzymes that help proteins function appropriately Coenzymes are organic molecules that loosely bond to the active site of an enzyme and aid in substrate concentration to help the enzyme work better While Cofactors are inorganic and do not bind to the enzyme.
