Proteins: The Body’s Building Blocks

Proteins: The Body’s Building Blocks

What is Protein? • Protein: an energyyielding nutrient composed of carbon, hydrogen, oxygen, and nitrogen. • Protein are polymers of amino acids linked together by peptide bonds. • Protein are key constituents of food, contributing towards organoleptic properties (particularly texture) and nutritive value

Protein in the Body Muscle

Bone

Skin

Other: blood, glands, nerve tissue

How Does the Body Use Protein? • Functions of protein – Provide structural and mechanical support – Maintain body tissues – Functions as enzymes and hormones – Help maintain acid base balance – Transport nutrients – Assist the immune system – Serve as a source of energy when necessary

Amino Acids Types of Amino Acids • Dispensable Amino Acids: Your body can produce these on its own. – Your body can synthesize 11 of the amino acids from the other amino acids

• Indispensable Amino Acids: The remaining 9 amino acids must come from your diet – also called essential amino acids – You must obtain them from the foods you eat since your body cannot make them

Complete proteins: • Foods containing all the essential amino acids Examples: fish, meat, eggs, milk, cheese Incomplete proteins: • Foods that are missing some essential amino acids Examples: Legumes, nuts, whole grains

Protein Synthesis

Protein digestion

Denaturation of Proteins • Denaturation is a change in a protein which causes an alteration in its physical and/or biological properties without rupture of its peptide bonds. • Denaturation of protein occurs when there is a distruption in any of the bonds that stabilize the secondary , tertiary, or quaternary structures. The primary is not affected. • Denaturing agents include :

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Heat Acids Bases High Salts Concentration Organic Solvent and Various Organic Solutes Mechanical agitation