Table 1.
Fusion partner proteins, which enhance expression and simplify purification
| Fusion partner | Molecular weight (kDa) | Purification method |
|---|---|---|
| 6× Hisa-SUMO | 12.2 | Ni–NTAa |
| CTHS | 7 | NTHS |
| GST | 27.3 | Glutathione–Sepharose |
| 6× His-NusA | 58.4 | Ni–NTA |
| MBP | 45 | Amylose resin |
| TRX | 14.3 | ThioBond resin |
| 6× HIS-Ub | 8.6 | Ni–NTA |
| Flag peptide | 1 | Anti-Flag antibodies |
Abbreviations used: SUMO, small ubiquitin modifying protein; Ni–NTA, nickel–nitriloacetic acid; CTHS, C-terminal half of SUMO; NTHS, N-terminal half of SUMO; GST, glutathione S-transferase; MBP, maltose binding protein; Trx, thioredoxin; Ub, ubiquitin.
a
The N-terminus of SUMO is very flexible and can accommodate a variety of affinity tags (e.g., GST). The SUMO system can therefore be tailored to the researcher’s desired affinity tag.