Table 2. Substrate specificities for the PLB1 enzyme from C. gattii.
PLB and LPL activities were measured by the radiometric and colorimetric assays respectively as described in the Experimental section. The reactions were performed using 500 μM of the various phospholipids at pH 5.0, and 40 μM of the lysophospholipids at pH 5.0 (30 s incubation) and pH 7.0 (5 min incubation). Results are expressed as the percentage of the control value (100%), where this represents a specific activity of 12.5±1.5 μmol/min per mg of protein for PLB (DPPC as substrate) and 82.8±9.4 μmol/min and 3.5±0.3 μmol/min per mg of protein for LPL at pH 5.0 or pH 7.0. BLD, below the limits of detection.
| Relative activity (%) | ||||
|---|---|---|---|---|
| LPL | ||||
| Substrate | PLB | pH… | 5.0 | 7.0 |
| DPPC | 100 | - | - | |
| DOPC | 2 | - | - | |
| DOPE | 11 | - | - | |
| DOPS | BLD | - | - | |
| PA | PA | - | - | |
| PI | BLD | - | - | |
| Sphingomyelin | 3 | - | - | |
| Triolein | BLD | - | - | |
| Palmitoyl carnitine | BLD | - | - | |
| 1-Palmitoyl lyso-PC | - | 100 | 100 | |
| 1-Oleoyl lyso-PC | - | 30 | 667 | |
| Lyso-PI | - | BLD | BLD | |
| 1-Palmitoyl lyso-PE | - | BLD | 100 | |
| 1-Palmitoyl lyso-PS | - | 70 | 100 | |