fungal lactase question?

Question

Fungal lactase, a blue protein found in wood-rotting fungi, is 0.340% Cu by mass. If a fungal laccase molecule contains 4 copper atoms, what is the molar mass of fungal lactase?

Answer 1

Let copper be called Cu. Let fungal lactase be called F. Atomic weight:Cu=63.5

4molCu/1molF x 63.5gCu/1molCu x 10000gF/34gCu = 74706g/mole

Answer 2

Check what they act on, and substitute the ending with the suffix -ase. Lipids are digested by lipase, proteins by protease (gastric and pancreatic), sucrose is digested by sucrase (also called invertase), etc.