"_A_ protein does all that" is.

Or by "proteins do everything" do you mean to say that single proteins often do complex operations like that?

I don't find it remarkable that complex operations get done. I just assumed the operations were built out of smaller and simpler steps. That was a pretty complex sounding operation that I would have thought involved at least 3 or 4 different steps performed by different molecules, one that locates, one that cuts, one that rotates, one that joins, etc.