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Flashcards in B2.007 LG Deck (19):
1

how do you determine the rate of reaction?

slope of concentration vs time

2

what is the purpose of an enzyme inhibitor?

the ligand binds and diminished catalysis to prevent a rxn from occuring

3

what characterizes a reversible inhibitor?

ligand readily dissociates

4

what characterizes an irreversible inhibitor?

ligand does not dissociate before the protein degrades or the patient dies; may be a covalent bond

5

what are the 3 types of reversible inhibitors?

competitive, non-competitive, uncompetitive

6

what is Km?

the [S] at half of vmax

7

what is on the y axis of a lineweaver-burke plot?

1/v0

8

what is on the x-axis of a lineweaver burke plot?

1/[S]

9

what do the x and y intercepts of the lineweaver-burke plot represent?

x axis: Km
y-axis: vmax

10

how do competitive inhibitors work?

compete with substrate for same form/site of the enzyme

11

which step is affected by competitive inhibition?

binding step only

12

how does a competitive inhibitor affect an enzyme activity curve?

Km increases
Vmax stays the same

13

what does a larger Km indicate?

less effective enzyme, takes a higher substrate concentration to get the same result as an enzyme with a lower Km

14

how to non-competitive inhibitors work?

inhibitor can bind to either just the enzyme, or the ES complex and inactivate it

15

what would be functionally similar to having a non-competitive inhibitor present?

having less enzyme

16

how does non-competitive inhibition affect an enzyme activity curve?

Km stays the same
vmax decreases (like having less enzyme)

17

how does uncompetitive inhibition affect an enzyme activity curve?

changes Km and vmax

18

how do aspirin and ibuprofen inhibit COX differently?

ibuprofen is reversible and is secreted within 24 hrs
aspirin is irreversible and persists until entirely new platelets are made 7-10 days later

19

which type of reversible inhibition does irreversible inhibition mimic on the enzymatic activity curve?

non-competitive; less overall enzyme function