PG. 19 – 29(SAME PAGES FOR THE NEXT FEW

CLASSES)

Protein(polypeptides, enzymes)

Building proteins

Proteins are polymers of amino acids

There are ~21 standard (natural) amino acids 9 are essential 12 are non-essential

What does this mean?

The vegan dilemma…

Animal foods contain all essential amino acids(Plant-derived foods do not)

Protein structure

Proteins vary enormously in size Smallest protein = 20 amino acids Large protein – 27,000 amino acids

The order of the amino acids determines the structure, properties and function of the protein

peptide bond

Protein structure

There are 4 levels of protein structure1. Primary structure

amino acid sequence

2. Secondary structure simple 3D arrangements

Alpha helix

Beta sheet

Protein structure

3. Tertiary structure 3D protein structure

4. Quaternary structure multiple proteins combined to make 1 functional unit

Protein function

Proteins can serve multiple functions1. Structural proteins

Muscle, bone, hair skin

2. Hormones Testosterone, estrogen, insulin

3. Enzymes “Big molecules that do stuff”

(eg. accomplish or aid in most cellular reactions)

Denaturation

The shape of a protein can be altered by heat or radiation

This denaturation causes the protein to unfold/uncoil and lose functionality

This change is usually permanent

Denaturation

Testing for proteins

Biuret solution Turquois solution becomes violet

Try this…

Pg. 27 #22 – 24