1. Uncommon Amino Acids, Amino Acids Forming Proteins & Primary Structure of a Protein ( ) pg
By: Emily, Kennedy

2. 14.5 What Are Uncommon Amino Acids?
Derived from common amino acids
Made from parent amino acids through post-transitional modification
-Post- transitional modification: modification of amino acid after the protein is synthesized

3. Examples of Uncommon Amino Acids
Connective tissue proteins, like collagen, contain hydroxyproline and hydroxylsine
Thyroxine is an extra iodine-containing aromatic group added as a side chain to tyrosine
-released as a hormone through globylin

4. 14.6 How Do Amino Acids Combine to Form Proteins?
Every amino acid contains a carboxyl and amino group (combined to make an amide)
- Ex. O
C – NH
Bonding in amino acids is a peptide bond
Product of 2 amino acids is called a dipeptide

5. Constitutional isomers are made by switching the groups around but may change the structure & function of the protein
When more amino acids are added, tripeptides (3 amino acids linked), tetrapides (4 amino acids linked), and many other proteins are formed.

6. Forms of chains Peptides are the shortest chain
Polypeptides contain a chain of 30 to 50 amino acids linked together
Proteins are the longest chain

7. Residues are separate amino acids in a chain represented by letters to stand for their names
C-terminal is an amino acid at the right end of a peptide with a free α - carboxylic group (-COOH)
N- terminal is an amino acid on the left end of a peptide with a free α – amino group (-NH3)

8. Examples Of C & N terminals
Alanylglycyllysine - AGK or Ala – Gly - Lys
C – terminal : Lysine
N – terminal : Alanine

9. 14.7 What Are the Properties of Proteins?
Continous peptide bonds make the backbone of a protein.
Side chains: R groups branched off of backbone
Adjacent bonds can rotate around C – N &
C – C

10. Zwitterions Proteins conatin zwitterions like amino acids
Glutamic & Aspartic are acidic
Lysine & Arginine are basic

11. pH
Isoelectric point (I.P.) is the pH point of equal positive and negative charges
pH above I.P. is a negative charge
pH below the I.P. is a positive charge

12. pH solubility pH solubility depends on the forces on the surface
Causes to repel each other
Least soluble at I.P.

13. Primary have a linear sequence of amino acids in a chain
Secondary have repeating patterns, pleated sheet, or coil
Tertiary are the overall formation of the chain
Quarternary contain more than one chain and show how they are related to one another