The Amino Acid Quizillator is currently only available in English, though localizations are in progress. The app store, even though told that only English is available, analyzes your application and if it finds any "stub" localizations, assumes them to be complete.
Amino Acid Quizillator
There are two ways. The easiest is to simply press the little x that appears beside the suggestion, in the popup. The second way is from iPhone's Main Menu, go to Settings | General | Keyboard and turn Auto-Correction "OFF". This will turn it off for all applications.