[mathgenius]

The ammonia maser uses proton tunnelling.. the guy who invented that also got "laughed out of the room". Well, it's probably a different pressure / temperature than enzyme kinetics, but those physicists, they like to own the quantum and not let anyone else have it. :-)

[jeffwass]

When I studied undergraduate quantum mechanics (physics dept, many years ago) one of our homework problems involved oscillation of the ammonia atom. Ie, the three hydrogen atoms form a triangle, and the nitrogen atom is in a superposition of states above or below the hydrogen plane.

Iirc, given some estimate of the relative potential energy barrier formed by the hydrogen atoms, we showed that the nitrogen atom would effectively oscillate between the up and down states and calculated the frequency of oscillation.