Enzymes-and-its-functions.pptx. Enzymes work

This is a presentation on how enzymes function

1. Enzyme Structure and Function

2. 2 Enzymes are molecules that help in speeding up the chemical reactions that occur in cells. This function of enzymes is known as catalysis .

3. 3 Enzymes are essential to the body’s normal functions. Many of these end with the suffix -ase .

4. 4 Examples of Enzymes Enzyme Function Amylase an enzyme found in saliva that helps digest starch Trypsin an enzyme found in the small intestine that helps break down proteins

5. 5 Examples of Enzymes Enzyme Function Helicase an enzyme that helps in unwinding DNA in the process of replication Lactase an enzyme that helps in breaking down the sugar lactose

6. Protein Structure 6 Tertiary Quaternary Primary Secondary The primary structure of a protein refers to the specific sequence of amino acids in a polypeptide chain.

7. Protein Structure 7 Tertiary Quaternary Primary Secondary The secondary structure refers to the protein’s folding pattern.

8. Protein Structure 8 Tertiary Quaternary Primary Secondary The tertiary structure refers to how the polypeptides form the shape of the molecule.

9. Protein Structure 9 Tertiary Quaternary Primary Secondary The quaternary structure refers to the subunits of the protein.

10. 10 Binding site amino acid residues that function to bind or accommodate the substrate molecule Enzyme Structure

11. 11 Catalytic site amino acid residues in the active site that serve to speed up or catalyze the reactions once binding has occurred Enzyme Structure

12. 12 Enzyme-substrate binding Enzyme-Substrate Complexes Substrates A substrate is a molecule that the reactions of which are catalyzed by the enzymes. Each enzyme is specific to a substrate.

13. 13 Enzyme-substrate binding Enzyme-Substrate Complexes Products Once the enzyme and substrate are bound to each other and the reaction has occurred, a product is then produced by the enzyme.

14. Enzyme-Substrate Models 14 Models Lock-and-Key: The specific shape between the active site and the substrate allows only that type of binding to occur between these two molecules. Induced Fit: Interaction is initially weak but the bond strengthens as the active site is modified.

15. Enzyme-Substrate Models 15 Lock-and-Key Induced Fit

16. Enzyme-Substrate Models 16 Lock-and-Key Induced Fit

17. 17 Why is it important for the protein’s active site to interact with the substrate?

18. 18 A good indicator for identifying whether a molecule is an enzyme is the presence of the suffix -ase. However, not all enzymes end with that suffix. Notable examples are the digestive enzymes pepsin, pepsinogen, trypsin, and rennin.

19. Functions of Enzymes 19 Functions Catalysis of chemical reactions Functions in cellular processes Several functions in the body

20. Functions of Enzymes 20 Enzymes as Catalysts Catalysis is the speeding up of reaction rates that are specific to the type of substrate and enzyme involved. Difference in the activation energy between a catalyzed and an uncatalyzed reaction

21. Functions of Enzymes 21 Enzymes as Catalysts The lowering of the activation energy is possible because enzymes modify the reactants into a state known as the transition state . Transition states of the reactants allow the catalysis of their reactions.

22. Functions of Enzymes 22 Enzymes’ Roles in the Body Function Enzymes Involved Digestion Enzymes like amylase, trypsin, pepsin, lactase, and others help in breaking down molecules for digestion. Cell division Enzymes like the cyclin-dependent kinases (Cdks) help in modifying proteins for cell division.

23. Functions of Enzymes 23 Enzymes’ Roles in the Body Function Enzymes Involved Nervous function Acetylcholinesterase helps in the breakdown of acetylcholine, which is necessary for nerve function. DNA replication Many enzymes, like helicase and DNA polymerase, all help cells replicate DNA.

24. 24 Identify the term being described in each of the following statements. This function of enzymes refers to their ability to speed up chemical reactions. This is the amount of energy needed for a chemical reaction to begin. This is the molecule, the reaction of which is catalyzed by the enzyme.

25. 25 Refer to the following graph to answer the questions below. Write the number that corresponds to your answer. Which part of the graph symbolizes the reactants? Which signifies the presence of an enzyme? Which signifies a faster rate of chemical reactions?

26. 26 Enzymes are biomolecules that help in speeding up the chemical reactions that occur in cells. Cells will require a large amount of energy to drive chemical reactions if enzymes are not present.

27. 27 Each enzyme has an area known as the active site , which is the area that recognizes the substrate molecule. For enzymes to perform their specific functions, they usually need to bind to a substrate. A substrate is a molecule, the reactions of which are catalyzed by enzymes.

28. 28 In the lock-and-key model , the specific shape between the active site and the substrate allows only that type of binding to occur between the two molecules.

29. 29 The induced-fit model states that the interaction between the enzyme’s active site and the substrate is initially weak but leads to the modification of the active site to strengthen the bond between the two molecules.

30. 30 Enzyme-substrate complex models vary according to whether the active site changes its shape in the presence of substrate molecules.

31. 31 31 What is the difference between the catalytic site and the binding site? Explain. Challenge Yourself