BGM1002/L03 Proteins In Health

Question 1

How many subunits does myoglobin consist of?

Answer 1

1 - tertiary structure

Question 2

How many subunits does haemoglobin consist of?

Answer 2

4 - tertiary & quaternary structure

Question 3

What is the tertiary structure of a protein?

Answer 3

Overall 3D shape

Question 4

What are the ‘chunks’ that proteins fold into called?

Answer 4

Domains

Question 5

How many amino acids long is a typical domain?

Answer 5

100-200

Question 6

What is the term given to related amino acid sequences which give similar structures?

Answer 6

Structural homology

Question 7

What is better conserved: structure or sequence?

Answer 7

Structure

Question 8

Where is protein folding encoded?

Answer 8

Amino acid sequence - primary encoded

Question 9

What database holds all amino acid sequences/protein structure data?

Answer 9

Protein Data Back (PDB)

Question 10

What 2 programmes are able to predict protein structure?

Answer 10

ML & LLM

Question 11

What can quaternary proteins bind to?

Answer 11

Other protein chains (homo-hetero interactions)
Small molecules (metals/cofactors)

Question 12

How does myoglobin/haemoglobin bind the haem cofactor?

Answer 12

Porphyrin ring with iron coordinated
Globin protein coordinates iron axially

Question 13

What is myoglobin?

Answer 13

Monomer that binds oxygen in muscle and delivers oxygen to muscle in low saturations

Question 14

What is haemoglobin?

Answer 14

Tetramer that binds oxygen in lungs/blood and releases oxygen to tissues in low saturations

Question 15

What does Hb’s oxygen affinity depend on?

Answer 15

Amount of blood oxygen

Question 16

What other factors can affect Hb’s affinity for oxygen? (3)

Answer 16

Chloride ions
Bis-phosphoglycerate
Protonation state of Hb
Carbon dioxide binding
Ligand binding state

Question 17

What kind of disease is Sickle Cell Anemia?

Answer 17

Autosomal recessive

Question 18

What mutation causes sickle cell anemia?

Answer 18

Subsitution E6V

Question 19

What causes Cystic Fibrosis?

Answer 19

Truncation of CFTR protein

Question 20

What kind of mutation causes CF?

Answer 20

Missense (incomplete protein/premature stop codon)

Question 21

What does CFTR stand for?

Answer 21

Cystic Fibrosis Transmembrane Conductance Regulator

Question 22

What is Phenylketonuria (PKN)?

Answer 22

Loss and poor function of phenylalanine hydroxylase

Question 23

What is Type 1 Diabetes?

Answer 23

Autoimmune disease which causes destruction of pancreatic beta cells, preventing insulin production

Question 24

How does blood clotting occur?

Answer 24

Platelets aggregate to stop bleeding by forming a clot - clotting cascade

Question 25

When does the clotting cascade occur?

Answer 25

In response to endothelial damage

Question 26

What is haemophilia?

Answer 26

Poor blood clotting due to deficiency in factor VIII (A), IX (B) or low levels of factor XI (C)

Question 27

What type of disorder is haemophilia?

Answer 27

X-linked