Table 2. Activities of PfTR Mutant Enzymes That Have C-Terminal Disulfide Ring Sizes with Various Substrates.
| mol of NADPH min–1 (mol of TR)−1 |
|||||
|---|---|---|---|---|---|
| enzyme | PfTR | ring size | 90 μM Trx | 300 μM selenocystine | 5 mM lipoic acid |
| PfTR-GC1GGGKC2Ga | 1 | 20 | 500 ± 20 | 410 ± 30 | 90 ± 10 |
| PfTR-GC1GGGC2Ga | 6 | 17 | 0.4 ± 0.3 | 60 ± 3 | 75 ± 5 |
| PfTR-GC1GGKC2Ga | 7 | 17 | 8 ± 1 | 190 ± 10 | 125 ± 5 |
| PfTR-GC1GGGGKC2Ga | 8 | 23 | 10 ± 1 | 340 ± 20 | 100 ± 5 |
| PfTR-GhC1GGGKC2Gb | 9 | 21 | 20 ± 1 | 190 ± 10 | 100 ± 5 |
| PfTR-GC1GGGKhC2Gb | 10 | 21 | 3 ± 0.3 | 150 ± 6 | 140 ± 6.5 |
a
Recombinant protein produced as a GST fusion.
b
Recombinant protein produced as an intein fusion via semisynthesis.