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#1




enzyme kinetics..
consider a reaction that can be catalyzed by one of two enzymes, A and B, with the following kinetics,
Km (M) Vmax (mmmol/min) A. 5 x 106 20 B. 5 x 104 30 6. At concentration of 5x104 M substrate, the velocity of the reaction catalyzed by enzyme A will be A. 10 B. 15 C. 20 D. 25 E. 30 kindly answer with explanation because i'm just stuck with this....your response will be appreciated.. thankuu 
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fizA (05212014) 
#2




first of all rule out the last two options because the enzyme cant work beyond it Vmax which is 20.
then rule out the first option bcoz thats the velocity at Km i.e 5 x106 . u r left with B and C now the value 5 x 104 is far above the Km so i m `guessing` the enzyme is working at its Vmax. they dont expect you to solve the complicated calculations on exam but if you want to make sure then solve the problem with lineweaverburk equation and u will get the answer C. 20 
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#3




Quote:
but i didnt get what is this value: 5 x106?? can you please clear it out? thank you 
#4




Quote:
5x 106 represent the conc of the S= Km for enz A, so at 5x104 definitely the enz will work at its vmax which is 20 so C is the correct answer. 
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CallingDrAsh (01092014) 
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