I did a domestic to shengen transfer with air Berlin. 50 minutes connecting time. Although I missed my connecting flight due to late arrival of flight. However. If discount the delay I found from the moment the flight atrive to the moment I reached from a gate to c gate it took me more than 50 minutes...there was 5 minutes waitong for jet bridge. 25minutes waiting forlluggage even though the bag was priority. The walk to c gate is a minimum 10 minutes. They check luggage tag on exit of luggage area is not helpful. And the awful thing is even if I have made it on time they would not accept my checkin luggage duw to cut off time. Remember txl does not provide luggage transfer facilities.

If you are from international you have to add 20 minutes for passport check and 20 minutes for accepting your checking luggage.

Provide you have no delay anf your arrival gate and departure gate is both in a gate then you should be fine. However if you need to make a run between a and c gate...bless you.