An enzyme binds to a competitive inhibitor with Kd = 1.2 × 10-6 M at pH 7.0 and 25°C.

Question

Question

An enzyme binds to a competitive inhibitor with K_d = 1.2 × 10^-6M at pH 7.0 and 25°C.

(a)At what inhibitor concentration will 75% of the enzyme be bound to the inhibitor if there is no substrate present?

(b) This enzyme has a Km of 4.0 × 10^-5 M and a Vmax of 50 μM/s. At a substrate concentration of 3.0 × 10^-4 M, calculate

(i) the velocity of reaction in the presence of the inhibitor at 4.8 x 10^-5 M

(ii) the degree of inhibition.

Answer 1

Answer #1

Answer 2

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An enzyme binds to a competitive inhibitor with Kd = 1.2 × 10-6 ​M at pH 7.0 and 25°C.