Reviewer comments are in complete contrast about research article
Since it was the editor that said you need a thorough "response", I think you need to revise. It sounds like s/he is trusting the second reviewer. Think especially about the significance. It may be that it is there, but you didn't state it clearly enough. 

I doubt that the editor will respond favorably to such an email. Just re-think your  paper and do a revision. You don't need to explicitly change it for any particular reviewer comment, but you need to consider what the reviewer has said and how you can improve it if possible. 

It may just be that one of the reviewer (either one) has missed something, but you don't really know which.