Table 3.
Summary of mutant data on ΔpH of conformational change relative to WT
| ΔpHa |
||||
|---|---|---|---|---|
| ELISA | Trypsin | Polykaryon | Average | |
| H171A | + 0.4 | + 0.4 | + 0.4 | + 0.4 |
| H171Y | − 0.3 | − 0.4 | − 0.3 | − 0.3 |
| K512A | − 0.3 | − 0.1 | − 0.1 | − 0.2 |
| K512E | − 0.2 | − 0.1 | − 0.1 | − 0.1 |
| Q1052A | − 0.2 | 0.0 | 0.0 | − 0.1 |
| Q1052E | − 0.1 | + 0.1 | + 0.1 | 0.0 |
| H1062A | + 0.1 | + 0.2 | + 0.1 | + 0.1 |
| H1062F | − 0.1 | − 0.1 | − 0.2 | − 0.1 |
| H1062R | − 0.1 | + 0.1 | 0.0 | 0.0 |
| D1092A | + 0.2 | + 0.4 | + 0.3 | + 0.3 |
| T1112A | + 0.1 | 0.0 | + 0.1 | + 0.1 |
| T1112H | + 0.6 | + 0.6 | + 0.6 | + 0.6 |
| T1112V | + 0.3 | + 0.3 | + 0.3 | + 0.3 |
| D1122A | + 0.5 | + 0.5 | + 0.5 | + 0.5 |
| H1062A, T1112A | + 0.4 | + 0.4 | −b | + 0.4 |
| H1062F, T1112V | + 0.4 | + 0.4 | +/−c | + 0.0 |
| H171Y, H1062A, T1112A | + 0.1 | 0.0 | + 0.1 | + 0.1 |
a
The values given for each assay represent the average from a minimum of three experiments. In all cases the range among replicates was less than 0.1 pH units.
b
No polykaryon formation detected at any pH.
c
Only low levels of fusion detected, and only at pH 0.1 or more lower than WT