在软件模拟分析的基础上，运用半理性设计转换传统去除N-糖基化的方式，同时在反向转角区引入具有增强芳香族序列(enhanced aromatic sequence, EAS)特征的新N-糖基化，提高了碱性果胶酶(alkaline polygalacturonate lyase, PGL)的热稳定性，获得了高品质的PGL工程菌。将355位点的苏氨酸突变成突变能低的色氨酸来去除353位点的N-糖基化,酶的半衰期提高了176%，但与目标值仍相距甚远；再将127和137位点同时引入新N-糖基化,使酶的半衰期达到1.35 h，与目标值接近。在酶的反向转角区引入具有EAS特征的新N-糖基化,对提高酶的热稳定性具有显著促进作用。

On the basis of modeling analysis by software, the traditional deglycosylation way was changed while new N-glycosylation with enhanced aromatic sequences (EAS) was introduced into the reverse turn of PGL through semi-rational design.In consequence, the thermostability of alkaline polygalacturonate lyase (PGL) was improved and a PGL engineering bacteria with higher quality was obtained.Removing the N-glycosylation in N353 by replacing the threonine at site 355 with tryptophan that has low mutation energy raised the half-life of PGL by 177%, which was still far from the target yet.Then, introducing new N-glycosylation in site 127 and 137 brought the half-life of recombinase PGL up to 1.35 h that was close to the target value.Introducing N-glycosylation with EAS into the reverse turn of enzyme could play a significant role in improving its thermostability.