Suppose you have an enzyme that has a KM value of 10uM for its substrate and...

Suppose you have an enzyme that has a K_M value of 10uM for its substrate and a V_max= 7umol-mg^-1min^-1. In the presence of a reversible inhibitor, the K_M value increases to 40uM and the V_max remains the same. What type of inhibitor is this and what is the K_I value of this inhibitor?

Expert Solution

Ans. Given,

Km increase from 10 µM to 40 µM.

V_max remains constant

Reversible inhibition is the characteristic of competitive inhibitor that simultaneously increase KM but leaves Vmax unaffected.

#2. Apparent Km = Km {1 + ([I] / KI)}

Or, Km,app = Km {1 + ([I] / KI)}

Where,

Km,app = 40 µM

Km = 10 µM

[I] = ?

KI = ? to be calculated.

Concentration of inhibitor [I] that leads to increase in Km must be known to get the value of KI.

Put the value of [I] (if you were provided, say in some part of this question) in above reaction to calculate KI.

queen_honey_blossom answered 3 years ago

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