Answer
Mice would die.
Work Step by Step
The protease would not not affect the DNA of the pathogenic bacteria. That would be taken up and expressed by the non-pathogenic bacteria, making them pathogenic and leading to the death of mice.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.