The Bambusa oldhamii phenylalanine ammonia-lyase (PAL) proteins, BoPAL1 and BoPAL2, exhibited different substrate specificities toward phenylalanine (Phe) and tyrosine (Tyr). Mutational analysis was conducted to study their substrate selectivity. All expressed wild-type and mutant BoPAL proteins manifested PAL activity; however, K_m and k_cat values were varied. BoPAL1 F133H and BoPAL2 F134H showed decreased k_cat/K_m values toward phenylalanine and significantly increased tyrosine ammonia-lyase (TAL) activities. BoPAL1 V197I and BoPAL2 I198 V showed opposite results regarding TAL activity, indicating that the Val or Ile residue prior to the active site, Ala-Ser-Gly, is essential for modulating Phe/Tyr substrate selectivity.

的绿竹苯丙氨酸氨裂解酶（PAL）的蛋白质，和BoPAL1 BoPAL2，显示出朝向苯丙氨酸（Phe）和酪氨酸（酪氨酸）不同的底物特异性。进行突变分析以研究其底物选择性。所有表达的野生型和突变型BoPAL蛋白都具有PAL活性。但是，K _m和k _cat值是变化的。BoPAL1 F133H和BoPAL2 F134H显示减少的k _cat / K _m苯丙氨酸值升高，酪氨​​酸氨解酶（TAL）活性显着增加。BoPAL1 V197I和BoPAL2 I198 V在TAL活性方面显示相反的结果，表明活性位点Ala-Ser-Gly之前的Val或Ile残基对于调节Phe / Tyr底物选择性至关重要。