Enzyme Kinetics

Question 1

Michaelis-Menten Equation

Answer 1

Question 2

Michaelis-Menten Graph

Answer 2

x-axis: subtrate concentration [S]

y-axis: reation rate, V

Question 3

Competitive Inhibitors

Answer 3

molecules that compete with substrate for binding at the active site

their inhibition can be overcome by adding more substrate

Vmax is not affected - you can get to the same Vmax but it takes more substrate

Km is increased - takes more time to get to 1/2 Vmax

Question 4

Noncompetitive Inhibitors

Answer 4

bind at an allosteric site, not at the active site

no matter how much substrate is added, the inhibitor is not displaced

Vmax is decreased

Km does not change

Question 5

Uncompetitive Inhibitors

Answer 5

only able to bind to the enzyme-substrate complex (cannot bind before the substrate has bound)

these inhibitors bind to allosteric sites

decreases Vmax

decreases Km

Question 6

Mixed-Type Inhibition

Answer 6

an inhibitor can bind to either the unoccupied enzyme or the enzyme-substrate complex

Km can either increase or decrease - depends on the affinity of the substrate and where it binds

Vmax decreases

Question 7

Lineweaver-Burk Plot

Answer 7

“double reciprocal plot”

x-axis: inverse of substrate concentration 1/[S]

y-axis: inverse of reaction rate 1/V

Question 8

Lineweaver-Burk Inhibition

Answer 8