1. Dopa oxidase – the perfect enzyme? Paul Beaumont / Kate Andrews
Kath Crawford / Lorraine Bruce

2. What characteristics do you look for in an enzyme practical?

3. Robust
Cheap
Versatile
Reliable
‘Living thing-based’
Easy to assay
Quick
Amenable to kinetic studies
Open to investigations e.g. temperature, pH

4. Tyrosinase / dopa oxidase /
catechol oxidase
Adapted from

5. Reaction

6. Materials
As per instruction sheet.

7. The Assay Banana ~ 2.5 g + 5.0 mL cold H2O
Centrifuge 2 min – enzyme extract
Zero colorimeter at 470 nm
In cuvette:
200 mL extract mL H2O
Place in colorimeter
Add 2.0 mL L-dopa solution and start stop-clock.
Measure colour every 20 s (or so...)