Peptidyl‐prolyl cis‐trans isomerase does not affect the Pro‐43 cis‐trans isomerization rate in folded calbindin D9k

FEBS Letters

Drakenberg, Torbjörn¹  Kördel, Johan¹  Thulin, Eva¹  Forsén, Sture¹ 

[1] Department of Physical Chemistry 2, Chemical Center, University of Lund, PO Box 124, S-221 00 Lund, Sweden

关键词: Proline cis-trans isomerism;    Peptidyl-prolyl cis-trans isomerase;    Cyclophilin;    Calbindin;    1H NMR;    Saturation transfer;   

DOI  :  10.1016/0014-5793(90)80697-H

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The calcium-binding protein calbindin D_9k has previously been shown to exist in two folded forms only differing in the proline cis-trans isomerism of the Gly-42-Pro-43 amide bond. This bond is located in a flexible loop connecting the two EF-hand Ca²⁺ sites. Calbindin D_9k therefore constitutes a unique test case for investigating if the recently discovered enzyme peptidyl-prolyl cis-trans isomerase (PPIase) can affect the cis-trans exchange rate in a folded protein. The ¹H NMR saturation transfer technique has been used to measure the rate of interconversion between the cis and trans forms of calbindin in the presence of PPIase (PPIase:calbindin concentration ratio 1:10) at 35°C. No rate enhancement could be detected.

【 授权许可】

Unknown