An enzyme has a Km for substrate of 10 mM and Vmax of 5 mol L-1
sec-1 at a total enzyme
concentration of 1 nM. At [S] = 10 mM, kcat is:
A) 2500 per M per sec.
B) 5000 per M per sec.
C) 1250 per M per sec.
D) 2500 per sec.
E) 5000 per sec.
We can use the following equation
Vmax = Kcat x [E]
Therefore ,
Kcat = Vmax / [E]
= 5 x 10 -6 / 10-9
= 5000 per sec.
Here it should be noted that the unit of Kcat is per sec.
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