Unfortunately, no.  While files can 'upgrade' from TurboTax to ProSeries, they can not 'downgrade' from ProSeries to TurboTax. 

Unfortunately, you will need to reenter all of your information when switching to TurboTax.

As a side note, be sure to use the "Forms Mode" on the CD/downloaded version of TurboTax.  The forms and worksheets are either identical or very similar to the ones in ProSeries.