ID 4.3.1.23 DE tyrosine ammonia-lyase. AN L-tyrosine ammonia-lyase. AN TAL. AN tyrase. CA L-tyrosine = (E)-4-coumarate + NH4(+). CC -!- Member of the aromatic amino acid lyase family, other members of CC which are EC 4.3.1.3, EC 4.3.1.24 and EC 4.3.1.25. CC -!- Far more active with tyrosine than with phenylalanine as substrate, CC but the substrate specificity can be switched by mutation of a single CC amino acid (H89F) in the enzyme from the bacterium Rhodobacter CC sphaeroides. CC -!- Formerly EC 4.3.1.5. DR Q3IWB0, TALY_CERS4 ; Q1LRV9, TALY_CUPMC ; Q0VZ68, TAM_CHOCO ; DR B8ZV93, TAM_MYXFU ; B8ZV94, TAM_MYXSM ; Q8GMG0, TAM_STRGL ; //