Proteins In Action

Question 1

Regulation inhibitors;

Answer 1

Directly affect active site
- Competitive

Question 2

Outline the indirectly affect active site;

Answer 2

Non-competitive

Allosteric

Question 3

Describe the antithrombin;

Answer 3

• plasma protein
• member of the serpin family (serine protease inhibitors)
• inhibits serine protease in blood clotting cascade

Question 4

Describe the function of antithrombin serpin;

Answer 4

• non-covalent interactions with proteases

•blocks active site

•. Acts as a substrate with very slow turnover

Question 5

Describe the allosteric activator-heparin;

Answer 5

• non-covalent interactions between heparin & antithrombin
• 2nd biggest biotechnology product
• heparin accelerates activity of antithrombin by 500-1000 fold

Question 6

Outline 3 regulation by phosphorylation;

Answer 6

1) serine

2) threonine

3) tyrosine

Question 7

What are kinases?

Answer 7

All have OH groups that can be phosphorylated by enzymes

Question 8

What does kinetics mean?

Answer 8

The rate of a phenomena
( how fast something changes)

Question 9

Outline reaction kinetics;

Answer 9

Reactant(s) —-> product(s)

Question 10

Outline enzyme kinetics;

Answer 10

enzyme

Substrates ——-> products

Question 11

Outline Vmax ( maximum velocity)

Answer 11

• fastest the enzyme can work
• all active sites filled with substrate being converted

Question 12

What is KM?

Answer 12

Substrate concentration at half of Vmax

Question 13

Under certain conditions KM measures…

Answer 13

How well enzyme binds to substrate (high KM is weak binding)