Engineered phenylalanine ammonia lyase polypeptides

The An engineered polypeptide comprising:

• a) an amino acid sequence having at least 90% sequence identity to reference sequence SEQ ID NO:4, where said amino acid sequence comprises an amino acid residue difference at position H307G/Q/M;
• and wherein said engineered polypeptide further comprises at least one or more of the following substitutions A39V, T54K, G59R, S73K, A112C, R134Q, A91V, Y158H, S180A, K195E, Q240R/W, T243EL, I245L, A256G, L257W/A, N270K, N290G, Y304H, R305M, E308Q, I326F, L349M, D353A/N, L364Q, A394V, S399N, N400K, P404A, L407V, F443H, N453G, Y459F, T460G, T463N, N474Q, E509L, Q521K/S, K522Y/F/N, T524S, P528L, S546R, and P564 G/L/M, when optimally aligned with the polypeptide of SEQ ID NO:4, and wherein said engineered polypeptide b) exhibits an improved property selected from i) reduced sensitivity to proteolysis, ii) increased tolerance to acidic pH, iii) reduced immunogenicity, or a combination of any of i), ii), or iii), as compared to the reference sequence SEQ ID NQ:4.