I am trying to overlay two structures. 1. Wild type enzyme and 2. A mutant, with a single point mutation on the wild type. However, somehow when I am opening the structures, both are overlapping automatically and showing as one structure.

  I need to have two separate strands overlay, so I can show the change in the active site pocket. I was hoping if anyone could shed some light on this issue.

Thanks,

Joydeep.