The present invention provides engineered phenylalanine ammonia lyase (PAL) polypeptides and compositions thereof, as well as polynucleotides encoding the engineered phenylalanine ammonia lyase (PAL) polypeptides. In some embodiments, the engineered PAL polypeptides are optimized to provide enhanced catalytic activity, as well as reduced sensitivity to proteolysis and increased tolerance to storage at elevated temperatures. In some embodiments, the engineered PAL polypeptides contain fewer phenylalanine residues than wild-type PAL polypeptides. The present invention also provides methods for the use of the compositions comprising the engineered PAL polypeptides for therapeutic and industrial purposes.
