Proteins

1. Proteins

2. Proteins: • Organic compound • Made up of C, H, O, N and some with S • Proteins are made up of long chains of the repeating units called amino acids.

3. There are 20 different types of amino acids that make up all proteins. 10 are essential to humans

4. 10 Essential Amino Acids:

5. The 20 amino acids combine in different orders to make up different proteins • Similar to the letters of the alphabet • 26 different letters combine to make 500,000+ words

6. Examples of foods rich in proteins:

7. Foods which are the best sources of amino acids:

8. S-T-E-A-K S E T K T A S E Blood Hair protein-keratin Muscle protein Skin protein-collagen

9. In other words……………. You are what you eat!!!!!!!

10. Or this……………. Your choice………………….

11. How much protein should you eat/day? Multiply your weight in pounds by 0.4 to estimate how many grams of protein you need each day. For example, a female who weighs 120 lbs would need about 48 grams of protein (120 lbs x 0.4 = 48 grams).

13. Function of Proteins: • Overall job of proteins is to: • Build new cells • Repair damages to our tissues and cells • Maintain our cells • Help digest our food • Regulate all cellular reactions

14. Proteins can be divided into two main types: 1. Structural Proteins: • They build and support our tissues

15. Examples of proteins: Collagen…………………skin Keratin……………………hair Actin and Myosin………….human muscles

16. 2. Functional Proteins: They perform specific functions within our bodies. Example:

17. Enzymes…speed up chemical reactions like digestion Insulin….transports glucose into cells Antibodies….destroy bacteria and viruses Hemoglobin…transports oxygen to cells

18. Amino acids bond together into chains with peptide bonds • A type of chemical bond lysine Amino acid Dipeptide Tripeptide Polypetptide Peptide Bond

19. All proteins have a very unique 3-D shape • If 3-D shape is altered the protein will be damaged. • Extreme cold to collagen…………Frost bite • Extreme heat to collagen…………3rd degree burn

20. Frying an egg: Egg White: 10% protein Yolk: 15% protein

21. Levels of organization of a protein: • 1st: Primary structure • Proteins are made in a linear shape • Straight line • A specific chain of amino acids is put together in the correct orderaccording to DNA’s code

22. One single change… Amino Acid Sequence Normal Sickle -Threonine – Proline – Glucine– Glucine -Threonine– Proline – Valine - Glucine

23. 2nd: Secondary Structure • The chain of amino acids becomes: • Coiled • Pleated • A spiral • Shape held in place with weak Hydrogen bonds.

24. 3rd: Tertiary Structure • The amino acid chain gets a 3-D shape • Each type of protein has its own 3-D shape • If shape is altered the protein can not function right.

25. 4th: Quaternary Structure • This level is achieved when two protein chains bond together to create a new protein.

27. Enzymes: -are catalyst -they are complex proteins that speed up all chemical reactions with our bodies. Enzymes are responsible for: -cell respiration -photosynthesis -Protein synthesis -Digestion Enzymes control every reaction within our bodies.

28. Enzymes are substrate specific. • Substrates are substances enzymes act upon like specific types of food. • Enzymes are specific types proteins. Therefore enzymes have specific 3-D shapes. • For each substrate/substance there is only one enzyme that can act upon it.

29. Take the example of digestion: Enzymes make the reaction of digestion occur 10 million times faster than it would without the enzymes. Digest candy bar with enzymes…. 20 min to 2 hours Digest same candy bar without enzymes…. 100 years

30. Substrate: Substance that an enzyme breaks down or acts upon. Ex: Our candy bar Due to their specific 3-D shape an enzyme can only act upon one type of substrate. There are different enzymes to break down the peanuts, the chocolate, the creamy filling, etc…..

31. Enzymes in the human alimentary canal and what they digest: The name of enzymes end in the suffix “ASE”.

32. Enzymes follow the lock and key hypothesis: For every type of substrate there is only one type of enzyme to break it down. Just like there is only one specific key which fits into a specific type of lock.

33. Enzyme animation

34. Let’s take a milk break….. Lactase Contains galactose and lactose sugars It’s a disaccharide

35. -The specific 3-D shape of an enzyme is called the active site. -point on the enzyme that “fits” around or into the substrate. -point where the substrate is broken.

37. Hyperlink -Enzymes are not altered or used up during a reaction. -Enzymes can be used over and over again.

38. Hyperlink Frostbite How environmental factors affect enzymes: Denaturing of enzymes: -extreme heat or coldness, and strong acids or bases can alter the shape of the active site making it less effective. (breaks the hydrogen bonds holding the 3D shape in place). -this is called the denaturing of the enzyme

40. Coenzymes: -Vitamins and minerals can bond to the enzyme and increase the rate of its function.

41. Competitive Inhibitors: -Certain drugs can bond to the enzyme and block the active site rendering it useless for doing its real job. Example: The drug marijuana contains the chemical THC. THC temporarily bonds to enzymes in our brain cells causing them to not function correctly thus causing the temporary feeling of being “high”.