Table 2.
Comparison of rates of 4NPA hydrolysis by artificial esterases.
| name | reference | molecule type | kcat (s−1) | KM (mM) | k2 (M−1s−1) |
|---|---|---|---|---|---|
| Zinc esterases (4NPA) | |||||
| MID1-zinc | (22) | helix-turn-helix dimer | 0.30 | 0.42 | 630 |
| Macrocyclic amine Zn(II) complexes | (33, 49, 50) | small molecule | -- | -- | < 1 |
| [Hg(II)]s[Zn(II)(H2O/OH−)]N(TRIL9CL23H)3n+ | (20) | trimeric peptide | 0.04 | 1.7 | 23 |
| Carbonic anhydrase II | (51) | natural protein, unnatural substrate |
53 | 21 | 2,550 |
| Metal-free esterases (4NPA) | |||||
| −OH | (32) | hydroxide ion | -- | -- | 9.5 |
| KO-42 | (26) | helix-turn-helix dimer | -- | -- | 0.29 |
| JNIIRO | (38) | peptide | -- | -- | 0.06 |
| S-824 | (25) | unselected catalytic antibody |
0.0054 | 3 | 2 |
| ECH13 | a | protein monomer | 0.018 | 0.057 | 320 |
| 43C9 | (28) | selected catalytic antibody |
25 | 0.05 | 470,000 |
| PDZ2 | (30) | thioredoxin redesign | 0.0005 | 0.17 | 3 |
a
Richter, Baker, personal communication