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Question 1

Protein conformations

Answer 1

Several levels on protein structure

Question 2

Levels of protein structures

Answer 2

Primary, Secondary, Tertiary, Quaternary

Question 3

1°(Primary) description

Answer 3

• Rarely have a function
• A chain of more than 50 amino aids linked by peptide linkages
• sequence and type of amino acid present varies

Question 4

1°(Primary) Chemical bonding

Answer 4

• peptide linkage between the NH2 of one amino acid and the carboxylic acid group of the next amino acid
• No R-group interactions

Question 5

2° (secondary) description

Answer 5

• One or more polypeptide chains individually coiled into a helix (called an alpha helix) or a beta-pleated sheet
• Ex. some parts of hemoglobin

Question 6

2° (secondary) chemical bonding

Answer 6

Hydrogen bonding and peptide links between the carbonyl and nitrogen of Aino acids that are 5 A.A. units apart

Question 7

Ex. Spiders webs

Answer 7

Pleated sheet

Question 8

Ex. Keratin

Answer 8

Alpha helix

Question 9

3° (tertiary) Description

Answer 9

• The folding of a coiled (helical or folded sheet) polypeptide chain
• curn on a curl
• Ex. hemoglobin

Question 10

3° (tertiary) chemical bonding

Answer 10

• hydrophilic and hydrophobic R-groups (ex OH with OH)
• Hydrogen bonding between distance amino acids
• disulfide bridges
• Prosthetic groups

Question 11

Prosthetic groups

Answer 11

• Inorganic attachments
• Ex. Heme

Question 12

4° (Quaternary) Description

Answer 12

• The assembly of 2 or more folded helical sub-units
• ie. 2 or more different peptide molecules

Question 13

4° (Quaternary) chemical bonding

Answer 13

• Hydrophobic interactions
• Hydrogen bonding
• R-group interactions
• Van der waal’s forces (intermolecular forces)

Question 14

Protein Denaturing

Answer 14

• Does not necessarily affect peptide bonds
• The unraveling of a portion which could ultimately alter the proteins function

Question 15

Factors that cause denaturing

Answer 15

Temperature, pH, Ion Concentration, Presence of other reactive chemicals

Question 16

Temperature

Answer 16

• Extreme temperatures (especially heat) breaks interactions that hold together protein conformations
• Ex. High environmental temperatures or fever

Question 17

pH

Answer 17

• Extreme pH’s can cause denaturing but certain proteins/enzymes have ideal pH ranges
• In humans issues come with lung and kidneys

Question 18

Ion Concentration

Answer 18

Certain ions can disrupt interactions between R-groups in proteins therefore causing denaturing

Question 19

Presence of other reactive chemicals

Answer 19

• Any chemicals that are highly reactive could disrupt interactions in proteins