Table 1. Comparison of biochemical properties and kinetic parameters of DTEase family enzymes.
| Strains | C. scindens a | C. cellulolyticum [15] | Ruminococcus sp.[16] | A. tumefaciens [13] | P. cichorii [20] | R. sphaeroides [14] |
| Optimum temperature (°C) | 60 | 55 | 60 | 50 | 60 | 40 |
| Optimal pH | 7.5 | 8.0 | 7.5–8.0 | 8.0 | 7.5 | 9.0 |
| Metal ion requied | Mn2+ | Co2+ | None | Mn2+ | None | Mn2+ |
| Half-life at 50°C (min) | 108 | >120 | >240 | 63.5 | NR | Approximately 60 |
| Substrate with highestspecificity | D-Psicose | D-Psicose | D-Psicose | D-Psicose | D-Tagatose | D-Fructose |
| k cat (min −1) | 1,827±136 (D-Psicose)350±26 (D-Fructose)44.2±3.8 (D-Tagatose) | 3,243.5 (D-Psicose)3,354.5 (D-Fructose) 184.8 (D-Tagatose) | 2,427 (D-Psicose)3,562 (D-Fructose)109 (D-Tagatose) | 2381 (D-Psicose)2068 (D-Fructose)270 (D-Tagatose) | NRb | NR |
| K m (mM) | 28.3±3.2 (D-Psicose)40.1±2.5 (D-Fructose)175.7±19.3 (D-Tagatose) | 17.4 (D-Psicose)53.5 (D-Fructose)244 (D-Tagatose) | 48 (D-Psicose)216 (D-Fructose)231 (D-Tagatose) | 12 (D-Psicose)24 (D-Fructose)762 (D-Tagatose) | 55 (D-Tagatose) | NR |
| k cat/K m(mM−1 min −1) | 64.5±4.8 (D-Psicose)8.72±0.63 (D-Fructose)0.25±0.02 (D-Tagatose) | 186.4 (D-Psicose)62.7 (D-Fructose)0.75 (D-Tagatose) | 51 (D-Psicose)16 (D-Fructose)0.47 (D-Tagatose) | 205 (D-Psicose)85 (D-Fructose)0.35 (D-Tagatose) | NR | NR |
| Equilibrium ratio between D-psicose and D-fructose | 28∶72 (50°C) | 32∶68 (55°C) | 28∶72 (60°C) | 32∶68 (30°C)33∶67 (40°C) | 20∶80 (30°C) | 23∶77 (40°C) |
a
The kinetic parameters of C. scindens DPEase are means of three replications ± standard deviation.
b
NR, not reported.