Table 1. PMT binding characteristics on various reconstituted membranes or natural membranes determined by SPR analysis.
The untreated and enzyme-treated natural membranes are designated as Native, Trypsin, SMase, PLCCab, or PLCSc. T indicates additional trypsin treatment after lipase treatment. The number of repeats N is the repeat of a set consisting of 4 recording signals from 4 flow channels of the same L1 chip. T-test p values for comparison among three reconstituted membranes were tabulated in supplementary Table S1, and among seven natural membranes in supplementary Table S2.
| Rapid Component
|
Slow Component
|
N (x4) | ||||||
|---|---|---|---|---|---|---|---|---|
| * Bmax (RU) | * KDx106 (M) | koff x102 (s−1) | Bmax (RU) | KD x106 (M) | koff x104 (s−1) | kon x10−2 (M−1s−1) | ||
| Reconstituted membranes | ||||||||
| PC | 243±2 | 3.78±0.12 | 29.6±24.3 | 165±30 | 0.54±0.10 | 8.46±2.77 | 16.1±6.2 | 3 |
| PC/PS | 221±1 | 1.57±0.03 | 24.4±15.6 | 185±30 | 0.41±0.11 | 5.58±0.75 | 14.0±3.0 | 3 |
| PC/SM | 264±3 | 2.80±0.13 | 26.6±15.5 | 256±42 | 0.84±0.21 | 6.57±0.51 | 8.22±1.93 | 3 |
| HEK-293T cell membranes | ||||||||
| Native | 530±29 | 12.4±1.1 | 4.9±1.0 | 802±193 | 0.68±0.24 | 5.7±1.1 | 9.3±2.8 | 4 |
| Trypsin | 201±1 | 3.07±0.15 | 5.3±0.7 | 572±52 | 0.60±0.07 | 6.4±0.3 | 10.8±1.3 | 2 |
| SMase | 4785±99 | 38.3±1.4 | 15.7±6.6 | 525±82 | 1.60±0.76 | 5.2±2.4 | 3.3±0.4 | 2 |
| SMase/T | 5516±64 | 48.5±0.9 | 14.0±5.5 | 616±54 | 1.46±0.63 | 5.2±1.7 | 3.7±0.5 | 3 |
| PLDCab | 423±3 | 14.3±0.3 | 12.9±3.3 | 423±83 | 0.91±0.32 | 8.6±1.3 | 10.2±2.8 | 3 |
| PLDCab/T | 416±3 | 9.44±0.24 | 11.1±0.3 | 548±37 | 0.79±0.19 | 7.5±0.8 | 10.2±3.0 | 2 |
| PLDSc | 313±8 | 7.18±0.32 | 11.6±4.6 | 518±48 | 0.68±0.13 | 6.8±1.1 | 10.2±1.7 | 3 |
*
Calculated from the RU at equilibrium of the rapid component, fitting to equation 5 using least-square method with a weight proportional to the concentration of PMT-N.