I posted a comment on this question, which has mysteriously vanished. It wasn't exactly ground breaking, though it was certainly constructive. I'm curious why it's gone…
It was not unconstructive but it was not very informative too. Moreover, it is obsoleted in the presence of the answer.
Q: How do DNA-binding proteins determine that they're binding to the correct DNA base pairs?
C: The major groove contains more information and can distinguish between C-G and G-C
If you disagree then I can undelete it. Comments are generally not used for answering (even if it is partial).