3.2.1.62 phlorizin + H2O low activity 3.2.1.62 phlorizin + H2O only substrate that is hydrolysed at the active site for phlorizin hydrolysis 3.2.1.62 phlorizin + H2O 5% of the activity of lactose hydrolysis 3.2.1.62 phlorizin + H2O hydrolysis located on a specific active site for phlorizin hydrolysis