Table 1.
Activities of the T(SH)2 metabolism enzymes in T. cruzi epimastigotes overexpressing different enzymes.
| Specific activity (nmol/min x mg soluble cell protein) |
||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| γECS | OE/Mock | GS | OE/Mock | TryS | OE/Mock | TryR | OE/Mock | TXN | OE/Mock | TXNPx | OE/Mock | |
| Wt | <3& | 1 | 23 ± 10 | 0.8 ± 0.3 | 1.2 ± 0.4§ | 1 | 334 ± 111 | 1.1 ± 0.4 | 33 ± 11 | 1.0 ± 0.3 | 66 ± 25 | 0.9 ± 0.3 |
| Mock | <3& | 1 | 28 ± 7 | 1 | 1.2$ | 1 | 291 ± 100 | 1 | 32 ± 11 | 1 | 73 ± 20 | 1 |
| γECS 1 | 12 ± 2* | 4 ± 1* | 23 ± 13 | 0.8 ± 0.5 | ND | ND | 341 ± 54 | 1.2 ± 0.2 | 30 ± 12 | 0.9 ± 0.4 | 85 ± 15 | 1.2 ± 0.2 |
| γECS 2 | 16 ± 7*ℵ | 5 ± 2* | 15 ± 6* | 0.5 ± 0.2* | ND | ND | 368 ± 63 | 1.3 ± 0.2 | 57 ± 33 | 1.8 ± 1.0 | 86 ± 16 | 1.2 ± 0.2 |
| γECS 3 | 22 ± 3*ℵ | 7 ± 1* | 18 ± 8 | 0.6 ± 0.3 | ND | ND | 321 ± 49 | 1.1 ± 0.2 | 27 ± 13 | 0.9 ± 0.4 | 88 ± 7 | 1.2 ± 0.1 |
| TryS 1 | ND | ND | 14 ± 6* | 0.5 ± 0.2* | 77 ± 24* | 64 ± 20* | 347 ± 120 | 1.2 ± 0.4 | 29 ± 8 | 0.9 ± 0.3 | 97 ± 37 | 1.3 ± 0.5 |
| TryS 2 | ND | ND | 11 ± 4* | 0.4 ± 0.2* | 95 ± 17* | 79 ± 14* | 283 ± 60 | 1.0 ± 0.2 | 27 ± 12 | 0.8 ± 0.4 | 67 ± 27 | 0.9 ± 0.4 |
| TryS 3 | ND | ND | 11 ± 4* | 0.4 ± 0.1* | 98 ± 45* | 81 ± 37* | 346 ± 160 | 1.2 ± 0.6 | 49 ± 26 | 1.5 ± 0.8 | 86 ± 30 | 1.2 ± 0.4 |
| TryR 1 | ND | ND | 20 ± 10 | 0.7 ± 0.3 | ND | ND | 6.1 ± 3.4 (x103)*# | 21 ± 12*# | 34 ± 13 | 1.1 ± 0.4 | 68 ± 16 | 0.9 ± 0.2 |
| TryR 2 | ND | ND | 21 ± 4 | 0.7 ± 0.5 | ND | ND | 6.8 ± 2.5 (x103)*# | 23 ± 8.5*# | 34 ± 11 | 1.1 ± 0.3 | 77 ± 27 | 1.1 ± 0.4 |
| TryR 3 | ND | ND | 14 ± 3* | 0.5 ± 0.1* | ND | ND | 14.4 ± 7.7 (x103)* | 50 ± 27* | 32 ± 12 | 1.0 ± 0.4 | 64 ± 12 | 0.9 ± 0.2 |
| TXN1-1 | ND | ND | 8 ± 3* | 0.3 ± 0.1* | ND | ND | 293 ± 71 | 1.0 ± 0.2 | 379 ± 175* | 12 ± 5* | 73 ± 23 | 1.0 ± 0.3 |
| TXN1-2 | ND | ND | 9 ± 5* | 0.3 ± 0.2* | ND | ND | 317 ± 69 | 1.1 ± 0.2 | 399 ± 164* | 12 ± 5* | 79 ± 19 | 1.1 ± 0.3 |
| TXN1-3 | ND | ND | 11 ± 6** | 0.4 ± 0.2** | ND | ND | 318 ± 51 | 1.1 ± 0.2 | 490 ± 230* | 15 ± 7* | 83 ± 22 | 1.1 ± 0.3 |
& threshold reliable specific enzymatic activity after the spurious ATPase activity was subtracted. ND: below the threshold confidence activity of the PyK/LDH coupled assay. § value determined by HPLC. $ value assumed to be similar to that of Wt. Values are the mean ± SD of at least three independent cultures. Student's t-test for non-paired samples *p < 0.01, **p < 0.05 vs. mock. ℵp <0.01 vs. γECS 1, #p < 0.05 vs. TryR3.