N‐terminal truncation of the variable subunit stabilizes spinach ferredoxin:thioredoxin reductase

FEBS Letters

Dai, S.²  Manieri, W.¹  Schürmann, P.¹  Franchini, L.¹  Stritt-Etter, A.-L.¹  Raeber, L.¹ 

[1]Laboratoire de Biochimie Végétale, Université de Neuchâtel, Rue Emile Argand 11, CH-2007 Neuchâtel, Switzerland

[2]Department of Molecular Biology, Uppsala Biomedical Center, Swedish University of Agricultural Sciences, Box 590, S-751 24 Uppsala, Sweden

关键词: Ferredoxin:thioredoxin reductase;    Variable subunit;    Spinach;    Mutagenesis;    Recombinant;    Stability;    FTR;    ferredoxin:thioredoxin reductase;    2-MET;    2-mercaptoethanol;   

DOI  :  10.1016/S0014-5793(03)00811-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The variable subunit of spinach ferredoxin:thioredoxin reductase (FTR) has an extended N-terminus compared to FTRs from other sources and this was proposed to contribute to the instability of the protein. We constructed two N-terminal truncation mutants of recombinant FTR by removing 16 or 24 residues from the variable subunit. The mutant proteins are readily expressed and show half-saturation values (S _0.5) for ferredoxin and thioredoxin f comparable to WT. However, truncation increases significantly their stability. Using the stabilized FTR an exposed Cys on its thioredoxin contact surface could be substituted without altering its properties, whereas the replacement of an active site Cys by Ser completely destabilized the protein.

【 授权许可】

Unknown