I was studying about restriction enzyme and I know that restriction enzyme recognize its substrate by recognizing distortion of the recognition site. And then the textbook said that:
"The distortion of the substrate and the subsequent binding of the magnesium ion account for the catalytic specificity of more than 1,000,000-fold that is observed for EcoRV endonuclease. Thus, enzyme specificity may be determined by the specificity of enzyme action rather than the specificity of substrate binding."
I don’t get why they said enzyme action rather than substrate binding. The distortion is the result of unique sequence of the substrate.
And what enzyme action exactly are they talking about? Are they saying that distortion of substrate is an enzyme action?