BioTechie

As a control in an experiment, I stored a sample ofrestriction enzyme to be used (3µL of Hind III) in a 37ºC incubator for 5 days- and it still worked just as well in a Lambda digest as samples stored at-20ºC! I wanted to show how the enzyme was inactivated, or at least lessactive, after storage at 37ºC - but couldn't. Why do all digest protocols recommend keeping these enzymes on ice while using them - when 5 days atat 37C didn't have an effect. Any ideas? I performed the test twice, not a pipet error because another control (no HindIII) showed no digestion as expected. I realize heat inactivation is 65C, but expected less activity at least. Can't find an answer on the internet so far. Would like to find an enzyme that is less effective after being kept at that temperature. Thanks. *labelled gel attached