It's not gen surg, but I know (at some point in the last couple years...not sure if he still is) the head of the ortho surg department at Vanderbilt was a DO. Once you get out of residency the job opportunities for MD and DO are basically the same.
I recently shadowed a general surgeon who is a DO. It was not in an academic setting, however. I'm sure at hospitals affiliated with a DO schoosl it's common.
I definitely know of both DO ortho and general surgeons who are working at a teaching hospital. The same hospital has an ortho residency but I'm not aware of a general surgery residency there.