15N NMR studies of the conformation of E. coli dihydrofolate reductase in complex with folate or methotrexate

FEBS Letters

Huang, Tai-huang¹  Huang, Fu-Yung²  Yang, Qing-Xian² 

[1] Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Republic of China;School of Physics, Georgia Institute of Technology, Atlanta, GA 30332, USA

关键词: Dihydrofolate reductase;    Methotrexate;    Folate;    NMR;    NADP+;   

DOI  :  10.1016/0014-5793(91)81077-L

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have employed ¹⁵N NMR to characterize the conformations of Escherichia coli dihydrofolate reductase (ECDHFR) in complex with [5-¹⁵N]folate or [5-¹⁵N]methotrexate (MTX). Two ¹⁵N resonances were observed for DHFR/MTX binary complex. The relative population of these two conformations is pH dependent. Addition of NADP⁺ or NADPH results in the disappearance of the low field resonance. In contrast, only one conformation was observed for both the DHFR/folate and DHFR/folate/NADP⁺ complexes. However, the ¹⁵N chemical shift of [5-¹⁵N]folate in the binary DHFR/folate complex is 7.28 ppm upfield from that of the ternary complex, suggesting the possible loss of a hydrogen bonding to N5 of folate in the ternary complex.

【 授权许可】

Unknown