Do isoenzymes have the same specific activity?

Answer 1

In addition to what Jen said, I would also like to point out that although isoenzymes by definition catalyze the same reaction, they often do it with different kinetic parameters.

For example, there may be different reaction order, affinities (K-constants), and the like, between two isozenzymes, even though they both perform the same product-to-substrate conversion.

Answer 2

I think they do. Isoenzymes catalyze the same reactions just in the different places. for example Fructose 1,6 bisphosphatase is an isonzyme that exists in two forms. One catalyzes reactions in cytosol and the onther one in the chloroplast stroma.