Determining how much enzyme to use based on activity units - (Mar/10/2010 )

Hello all, I have a question regarding the amount of a specific enzyme I need to use based on it's activity units. I have the feeling I'm making this more complicated then it is, so I want to doublecheck if I'm doing this right. So I have a particular enzyme which is 1.5 U/mg (1 U = amount of enzyme which liberates 1 umol substrate per minute under specific condtions), I am using 1 mg of substrate and am trying to figure out the correct amount of enzyme to use and keep coming up with different amounts. Would anyone care to help me out with this? Thank you.

how many umoles are in 1mg substrate?

you don't give much information.

(by the way, i'm also a nyy fan)

The MW of the substrate is 932, so 1 mg would be roughly 1.1 umol.

BTW, we win #28 this year!

so you need to use ~0.72mg of your enzyme (1.5u/mg*.72=1.08u; 1mg/.932=1.073umol).