Table 1.
SadA mutants generated and their phenotypesa
| Mutant | Mean speed (± SD) that 50% of cells remained adherent (no. of assays) | Actin localization |
|---|---|---|
| S924AS925A | 44.2 ± 6.3 (5) | Cortical |
| S924ES925E | 38.4 ± 10.1 (5) | Cortical |
| S940AS941A | 50.5 ± 4.9 (2) | Cortical |
| S940ES941E | 47 ± 5.7 (2) | Cortical |
| S950A | 63.5 ± 7.8 (2) | ND |
| S943AS944AS950A | ND | ND |
| S943ES944ES950E | ND | ND |
Seven unique SadA tail phosphorylation site mutants were generated during the course of the study. All mutants exhibited primary localization of SadA-GFP at the plasma membrane. Adhesion maintenance assays, as described in Materials and Methods, were conducted with multiple independent clones. The average speeds (in rpm) at which 50% of the cells remained adherent were estimated from graphs and used in the calculations. The number of independent assays performed for each strain is given in parentheses and was used to calculate the standard deviation. Actin localization was visually assessed on fixed cells probed with an antiactin antibody and was deemed to be cortical if strong signals were observed at the cell periphery. ND, not determined.