Question

An enzyme preparation has activity of 2 units per 20 ul and protein concentration 0.4mg/ml. The specific activity of this enzyme will be

Answer 1

Specific enzyme activity (SEA) = Enzyme activity (EA) / Enzyme conc. (EC)

In this case. EA = 2 U (2 umol/min) per 20 ul

Now, Talking about EC,

In 1 ml (or 1000 ul) amount of enzyme present is 0.4 mg (or 400 ug).

So, in 20 ul, amount of enzyme present is 400/1000 x 20 = 8 ug = 0.008 mg

So, SEA = 2 / 0.008 = 250 umol / min / mg