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

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 contribute the instability protein. We constructed two N-terminal truncation mutants recombinant FTR by removing 16 or 24 residues subunit. mutant proteins are readily expressed show half-saturation values (S(0.5)) for ferredoxin thioredoxin f comparable WT. However, increases significantly their stability. Using stabilized exposed Cys on its contact surface could be substituted without altering properties, whereas replacement active site Ser completely destabilized