大腸菌の　Ｔｒｋ／Ｋｔｒ／ＨＫＴ　トランスポーターの新規機能の解明

本研究旨在探索Trk/Ktr/ hkt型钾离子（K+）转运体的新特性。我们重点研究了大肠杆菌trk型转运体的独特特征。成功构建K+转运蛋白敲除突变体，分别检测TrkG和TrkH的单独活性。摄取实验显示TrkG和TrkH活性的不同特征，表明这两种转运体不相同，可能对生存能力有不同的生理功能。更好地了解大肠杆菌中的Trk转运蛋白将为其他Trk/Ktr/HKT超家族转运蛋白提供新的认识，这些转运蛋白不仅在细菌中表达，而且在酵母和作物植物等具有重要经济意义的生物中表达。

This proposed research aims to explore new feature of Trk/Ktr/HKT-type potassium ion (K+) transporter. We focused on to investigate the distinct feature of Escherichia coli Trk-type transporters. The K+ transporter knock-out mutants were successfully constructed to examine the sole activity of TrkG and TrkH, respectively. The uptake experiments showed a different characteristics between TrkG and TrkH activity, indicated that these two transporters are non-identical and possibly contribute to different physiological functions for survivability. The better understanding of Trk transporter in E. coli will give a new insight for other Trk/Ktr/HKT superfamily transporters that expressed not only in bacteria, but also in the economically important organisms, such as yeast and crop plants.