Hello. The short answer is NO!

Here is the long answer: You need to stabilize the cement board with thinset. That will both strengthen the floor and eliminate movement between your cement board and subfloor. Do not use a mastic or glue, use thinset for strength. First, dry lay all of the pieces down, cutting in the perimeter. Then mark around each piece with a marker. Then working section at a time, apply thinset directly to the subfloor and lay the board down. Make sure you screw down each board shortly after you apply the thinset while it is fresh so the board can sink down into the mud. Make sure you screw the edges down every two inches and the middle every four inches.