remove/undo wptexturize for portion of post

Hello.

I wrote a plugin that takes all input between these tages [pgn] … [/pgn] and processes the user input.

However, wordpress takes the liberty of beautifying the code by replacing certain sequences with special chars. For example, a double dash is replaced by an em-dash and so on. I believe this function is called wptexturize.

Is there a way in my plugin to remove/undo the effects of this beautification?

Thanks.