BGM1002/L01 Proteins Overview

Question 1

Why are proteins studied?

Answer 1

To understand how cells work.

Question 2

Give 2 examples of proteins in Medicine.

Answer 2

Herceptin - anticancer antibody
Insulin - protein hormone used to treat T1 Diabetes

Question 3

What is the active/targeted component in most vaccines?

Answer 3

Proteins

Question 4

In a 75kg human, what is the approximate protein weight?

Answer 4

Wet - 12kg
Dry - 25%

Question 5

Approximately what percentage of cell material is protein?

Answer 5

50%

Question 6

What percentage of protein in the body is muscle?

Answer 6

50-75%

Question 7

What structures can proteins form? (Give 5)

Answer 7

Cytoskeleton
Enzymes
Cell receptors
Toxins
Antibodies
Hair
Fingernails
Histones
Transporters
Ribosomal proteins
DNA/RNA polymerase

Question 8

How many different varieties of protein are in the human body?

Answer 8

Approximately 20,000.

Question 9

How many biogenic amino acids are there?

Answer 9

20/21

Question 10

How many levels of protein structure are there? Name them.

Answer 10

4 - Primary, secondary, tertiary, quaternary.

Question 11

What is the relationship between all proteinogenic amino acids?

Answer 11

They are L-isomers

Question 12

Name the 6 common aliphatic amino acids.

Answer 12

Alanine, Glycine, Isoeucine, Leucine, Proline, Valine.

Question 13

Name the 3 common aromatic amino acids.

Answer 13

Phenylalanine, Tryptophan, Tyrosine.

Question 14

Name the 2 common acidic amino acids.

Answer 14

Aspartic acid, Glutamic acid.

Question 15

Name the 3 common basic amino acids.

Answer 15

Arginine, Histidine, Lysine

Question 16

Name the 2 common hydroxylic amino aids.

Answer 16

Serine, Threonine.

Question 17

Name the 2 common Sulfur-containing amino acids.

Answer 17

Cysteine, Methionine.

Question 18

Name the 2 common amidic amino acids.

Answer 18

Asparagine, Glutamine.

Question 19

What type of reaction occurs during formation of a peptide bond?

Answer 19

Condensation.

Question 20

Which parts of the amino acids react during formation of a peptide bond?

Answer 20

Carboxylic acid and amino groups.

Question 21

What type of isomerisation can a peptide bond undergo?

Answer 21

Cis/trans

Question 22

What unit of measurement is used for a C-N peptide bond and what is it equal to?

Answer 22

Å (angstrom = 0.1 nm)

Question 23

In which way is the polypeptide backbone directional?

Answer 23

N-term to C-term.

Question 24

Which organelle synthesises proteins?

Answer 24

Ribosomes.

Question 25

What type of amino acids do ribosomal proteins have exclusively?

Answer 25

L-amino acids.

Question 26

What type of amino acids are found in some non-ribosomal proteins? Give one example.

Answer 26

D-amino acids - bacterial cell walls.

Question 27

What is a covalent bond?

Answer 27

The strongest molecular bond of two atoms sharing pairs of valence electrons.

Question 28

What are ribosomes composed of?

Answer 28

Large and small sub-units.

Question 29

How do ribosomes catalyse formation of peptide bonds?

Answer 29

By binding mRNA and charged tRNA molecules.

Question 30

What are amino acids delivered to the ribosomes by?

Answer 30

tRNA

Question 31

What occurs as a result of stopping peptide bond formation? Why is this useful?

Answer 31

It stops protein synthesis and kills the cell. It is useful as a drug target.

Question 32

What is a proteome?

Answer 32

The sum of all the proteins in a cell.

Question 33

How are proteins modified after translation?

Answer 33

Post-translational modification.

Question 34

What is a primary protein?

Answer 34

A single linear string of amino acids

Question 35

What is a secondary protein?

Answer 35

A folded 'backbone' of amino acids, in a regular arrangement

Question 36

What is a tertiary protein?

Answer 36

Overall 3-dimensional arrangement of bonded amino acids

Question 37

What is a quaternary protein?

Answer 37

A globular or fibrous structure with multiple strings of protein; a functional arrangement with other proteins or cofactors

Question 38

What is the CORN law?

Answer 38

A rule used to distinguish enantiomers from each other (whether an amino acid is an L-isomer or D-isomer).

Question 39

Which way is a protein read?

Answer 39

From the amino group to the carboxyl group

Question 40

What type of bond is a peptide bond?

Answer 40

Planar bond

Question 41

Which type of bond is the strongest of all molecular bonds?

Answer 41

Covalent bond (shared pairs of valence electrons)

Question 42

What effect does a mutation in the genome have on the resultant protein/amino acid?

Answer 42

It creates a variant protein/different amino acid

Question 43

What type of bodily response can occur due to spike proteins?

Answer 43

Autoimmune response